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Exhibit 2.9

                              SHAREHOLDER AGREEMENT


         THIS SHAREHOLDER AGREEMENT ("Agreement") is made to be effective as of
February 1, 2002 by and among Jens Oilfield Services, Inc., a Texas corporation
(the "Corporation"), Jens H. Mortensen, Jr., ("Mortensen") and Allis-Chalmers
Corporation, a Delaware corporation ("ACC")(each of Mortensen and ACC being
referred to individually as a "Shareholder" and collectively as the
"Shareholders") with respect to all of the now or hereafter issued and
outstanding shares of common or preferred stock or other issued and outstanding
securities of the Corporation (including options, warrants and convertible
instruments), presently or hereafter owned by each of the Shareholders (the
"Stock"). Any reference to Stock owned by a Shareholder shall mean all of the
Stock held in that Shareholder's name and including, but not limited to, any
community property interest of the Shareholder's spouse in such stock.

         WHEREAS, the Shareholders are presently the holders of record of all of
the issued and outstanding shares of the Stock of the Corporation; and

         WHEREAS, the Shareholders believe that it would be in the best interest
of the Shareholders and the Corporation to place certain restrictions upon the
right of any Owner of Stock to transfer any Stock owned by such Owner; and

         WHEREAS, the directors of the Corporation, having considered the
provisions of this Agreement, have resolved that in their opinions the
restrictions upon the transfer of the Stock of the Corporation and the
provisions for the redemption and/or purchase of the Stock, all as hereinafter
set forth, are in the best interest of the Corporation.

         NOW, THEREFORE, the parties hereto hereby agree as follows:

                                    ARTICLE I

                                   DEFINITIONS
                                   -----------

         Section 1.01. DEFINITIONS OF CERTAIN AGREEMENT TERMS. For purposes of
this Agreement, the terms hereinafter set forth shall have the following
definitions unless otherwise specifically stated.

         (a)      BANKRUPTCY CODE. The term "Bankruptcy Code" shall mean the
                  Bankruptcy Reform Act of 1978, as amended.

         (b)      BUSINESS DAYS. The term "Business Days" shall mean days that
                  are not Saturdays, Sundays, or legal holidays in the United
                  States or the State of Texas.

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         (c)      CLOSING. The term "Closing" shall have the meaning set forth
                  in Section 4.01 of this Agreement, unless "Closing" is
                  otherwise defined in a specific section.

         (d)      CLOSING DATE. The term "Closing Date" shall have the meaning
                  set forth in Section 4.01 of this Agreement, unless "Closing
                  Date" is otherwise defined in a specific section.

         (e)      COMPETING EMPLOYMENT RELATIONSHIP. A "Competing Employment
                  Relationship" shall exist between a person and the Corporation
                  if such person, directly or indirectly, without the prior
                  written consent of the Corporation, renders services for any
                  person (including self-employment) or entity other than the
                  Corporation (i) that are similar to the services he or she
                  renders or that other employees customarily render to the
                  Corporation, or (ii) that are similar to the services that the
                  Corporation customarily renders to its clients. For the
                  purpose of this definition Tex-Mex Rental & Supply Company, a
                  Texas corporation ("Tex-Mex") owned by Mortensen and his
                  family shall not be deemed a Competing Employment
                  Relationship.

         (f)      CORPORATION. The term "Corporation" shall mean Jens Oilfield
                  Services, Inc., a Texas corporation.

         (g)      EMPLOYMENT RELATIONSHIP. An Employment Relationship shall
                  exist between a person and the Corporation if such person is
                  employed by the Corporation on a continuing basis pursuant to
                  which such person customarily renders substantially all of his
                  or her business time and efforts to the performance of duties
                  assigned to him or her by the Corporation, subject to
                  reasonable periods of absence for vacations. An Employment
                  Relationship also shall be deemed to exist between the
                  Corporation and a person regardless of the quantum of business
                  time devoted by such individual to the performance of duties
                  assigned to him or her by the Corporation, so long as the
                  Board of Directors of the Corporation believes such person is
                  adequately performing his or her duties as an employee of the
                  Corporation.

         (h)      EVENT OF TRANSFER. The term "Event of Transfer" shall mean the
                  completion of any Transfer, as that term is defined herein.

         (i)      EXCESS OFFERED STOCK. The term "Excess Offered Stock" shall
                  have the meaning set forth in Section 3.03 of this Agreement.

         (j)      FIRST REFUSAL NOTICE DATE. The term "First Refusal Notice
                  Date" shall have the meaning set forth in Section 3.01 of this
                  Agreement.

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         (k)      NOTICE OF RIGHT OF FIRST REFUSAL. The term "Notice of Right of
                  First Refusal" shall have the meaning set forth in Section
                  3.01 of this Agreement.

         (l)      OFFER PRICE. The term "Offer Price" shall have the meaning set
                  forth in Section 3.01 of this Agreement.

         (m)      OFFERED STOCK. The term "Offered Stock" shall have the meaning
                  set forth in Section 3.01 of this Agreement.

         (n)      OFFEROR SHAREHOLDER. The term "Offeror Shareholder" shall have
                  the meaning set forth in Section 3.01 of this Agreement.

         (o)      OTHER SHAREHOLDERS. The term "Other Shareholders" shall, in
                  Article III, mean the Shareholders that are not the Offeror
                  Shareholder.

         (p)      OWNED. Stock referred to as being "owned" by any person shall
                  include all Stock owned (whether acquired before or after this
                  date) as the separate property of such person, all Stock owned
                  as the community property of such person and his or her spouse
                  that is registered in the name of such person, all Stock
                  acquired by gift, partition or other transfer of community
                  property Stock, and any shares into which any such Stock, or
                  any portion thereof, may be converted. A person who owns Stock
                  is sometimes referred to as an "Owner." While a spouse of a
                  Shareholder may own an interest in Stock that is deemed to be
                  "owned" by such Shareholder under this definition, the term
                  "Shareholder" as used in this Agreement does not apply to the
                  spouse of any such named party to this Agreement unless such
                  spouse also owns Stock.

         (q)      PERMITTED TRANSFERS. The term "Permitted Transfers" shall have
                  the meaning set forth in Section 3.07 of this Agreement.

         (r)      PURCHASE PRICE. The term "Purchase Price" shall have the
                  meaning set forth in Section 3.05 of this Agreement.

         (s)      SHAREHOLDER. The term "Shareholder" shall include all of the
                  individuals who own Stock in the Corporation who are parties
                  to this Agreement, and any persons who subsequently shall
                  become parties to this Agreement.

         (t)      SHAREHOLDER'S ESTATE. A "Shareholder's Estate" shall mean and
                  include a deceased Shareholder's executor, administrator or
                  similar personal representative (if one has qualified and is
                  then acting), and his or her surviving spouse, heirs,
                  beneficiaries, devisees and legatees to the extent, if any,
                  that their action is required in order to effect a full and
                  complete transfer of such deceased Shareholder's Stock
                  pursuant to the terms of this Agreement. The general agent of
                  the persons and entities comprising a Shareholder's Estate
                  shall be his or her duly appointed and qualified executor or
                  administrator, or his or her surviving spouse where no such
                  representative is appointed, and all notices and
                  communications hereunder shall be effected to and through such
                  general agent.

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         (u)      SHAREHOLDER'S STOCK. Stock referred to as being owned by a
                  Shareholder at any point in time, sometimes referred to as
                  "Shareholder's Stock", shall include any shares of Stock owned
                  by such Shareholder at such time.

         (v)      STOCK. The term "Stock" shall have the meaning set forth in
                  the introductory paragraph of this Agreement.

         (w)      THIRD PARTY OFFER. The term "Third Party Offer" shall have the
                  meaning set forth in Section 3.01 of this Agreement.

         (x)      TRANSFER. The term "Transfer" shall have the meaning set forth
                  in Section 2.01 of this Agreement.

         (y)      TRANSFEREE. A "Transferee" or "Transferees" shall include any
                  lineal descendant of a Shareholder, any custodian, guardian or
                  other representative for a lineal descendant of a Shareholder,
                  and the trustee of any trust created for the benefit of a
                  Shareholder's lineal descendant(s) and any other party who
                  succeeds to the ownership of any Stock originally owned by a
                  Shareholder whether by purchase, assignment, gift, bequest,
                  devise, levy, execution or any other means of transfer. At
                  such time as a Transferee shall become a Shareholder and
                  become a signatory to this Agreement, he or she shall cease to
                  be a "Transferee" hereunder. The Shareholder from whom a
                  Transferee acquired Stock, or the general agent of such
                  Shareholder's Estate if such Shareholder is deceased, shall
                  constitute the general agent for all of such Shareholder's
                  Transferees, and all notices and communications hereunder
                  shall be effected to and through such general agent.

                                   ARTICLE II

                          RESTRICTIONS AGAINST TRANSFER
                          -----------------------------

         Section 2.01. TRANSFER OF STOCK RESTRICTED. Each of the Shareholders
agrees that he, she or they will not in any way Transfer (as defined herein) any
of his or their Stock, or any right or interest therein, without the prior
written consent of the Corporation and the other Shareholders, except for
Permitted Transfers or other Transfer that meets the requirements of this
Agreement. "Transfer" shall, herein, mean the sale, exchange, assignment,
pledge, gift, hypothecation, transfer or other disposition (whether voluntary or
involuntary) by a Shareholder of his or her Stock, either directly or
indirectly, to any third party or any offer or attempt to accomplish any of the
foregoing. Transfer will specifically not include for purposes of this
Agreement, the pledge by ACC of its Stock in the Corporation to Wells Fargo
Credit, Inc. and Wells Fargo Energy Capital, Inc. (collectively, "WELLS FARGO")
pursuant to the financing of its acquisition of the Stock of the Corporation,

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which Stock has been pledged to Wells Fargo as of the date hereof or the
exercise of the Mortensen Option (as defined in Section 6.03 hereof). Any
purported Transfer in violation of any provision of this Agreement will be void
and will not operate to transfer any right, title, or interest in the Stock to
the purported Transferee, and will give the Corporation and the other
Shareholders an option to purchase such Stock in the manner and on the terms and
conditions provided in this Agreement. The right of the Corporation to exercise
its option to purchase the Stock is subject to the laws of the State of Texas
governing the rights of the corporation to purchase its own shares.


                                   ARTICLE III

                             RIGHT OF FIRST REFUSAL
                             ----------------------

         Section 3.01. NOTICE OF RIGHT OF FIRST REFUSAL. In the event that a
Shareholder receives a bona fide offer (a "Third Party Offer") for the purchase
of all or a part of his or her Stock (or any rights or interests therein) that
such Shareholder desires to accept, such Shareholder (the "Offeror Shareholder")
agrees to give written notice of such Third Party Offer (the "Notice of Right of
First Refusal") to the Secretary of the Corporation and to the other
Shareholders (the "Other Shareholders"). The notice must set forth the name of
the proposed Transferee, the number of shares to be transferred (the "Offered
Stock"), the price per share (the "Offer Price"), all details of the payment
terms, and all other terms and conditions of the proposed Transfer. A Third
Party Offer may not contain provisions related to any property other than the
Stock of the Offeror Shareholder, and the Offer Price shall be expressed only in
terms of cash contained in the proposed transfer. The Offeror Shareholder shall
deliver such Notice of Right of First Refusal to the parties noted above
immediately upon receiving such Third Party Offer, but in any event not less
than sixty (60) days prior to the date of the proposed Transfer. An offer for
the purchase of Stock in which property other than cash is to be exchanged for
the Stock shall not be considered a valid Third Party Offer hereunder.

         The last date that the Notice of Right of First Refusal is received by
the Other Shareholders shall constitute the "First Refusal Notice Date." The
Corporation shall be obligated to promptly determine the First Refusal Notice
Date following its receipt of a Notice of Right of First Refusal, and such date
shall be promptly communicated in writing by the Corporation to all Shareholders
within five (5) days of the determination of such date. For purposes of this
Section 3.01, a "Third Party Offer" to purchase part or all of a Shareholder's
Stock shall mean a written offer to purchase such Stock from a person or entity
unrelated to that Shareholder. Without limitation of the generality of the
foregoing, a Third Party Offer does not include an offer where the Shareholder
receiving such offer has an option or obligation to reacquire all or part of the
Stock covered by such offer.

         Notwithstanding the foregoing provisions of this Section 3.01, if the
proposed Transfer is entirely donative with no consideration to be received for
the proposed Transfer, the Offer Price therefor shall be equal to $10.00.

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         Section 3.02. PRIMARY RIGHT OF FIRST REFUSAL BY CORPORATION. The
Corporation shall have the sole and exclusive option to acquire all or any
portion of the shares of Stock offered for Transfer in accordance with the
provisions of the Notice of Right of First Refusal for a period of twenty (20)
days from the First Refusal Notice Date. The Corporation may exercise such
option by giving written notice of exercise to the Offeror Shareholder and to
all Other Shareholders prior to the termination of its exclusive option period.
Such notice of exercise shall refer to the Notice of Right of First Refusal and
shall set forth the number of shares of Stock to be acquired by the Corporation.

         Section 3.03. SECONDARY RIGHT OF FIRST REFUSAL BY OTHER SHAREHOLDER(S).
The Other Shareholders shall have the exclusive option from the twenty-first day
to the fortieth day following the First Refusal Notice Date, to acquire the
Offered Stock not being acquired by the Corporation in accordance with the
procedure described in this Section 3.03. The Other Shareholders may, by
agreement, allocate among themselves the right to acquire such part of the
Offered Stock that will not be acquired by the Corporation.

         In the absence of such an agreement between the Other Shareholders,
each Other Shareholder will be entitled to give written notice to the Offeror
Shareholder, to the Corporation, and to the Other Shareholders, within forty
(40) days from the First Refusal Notice Date, of such Shareholder's election to
acquire all or any part of such Offered Stock that is not being acquired by the
Corporation ("Excess Offered Stock"). If the Other Shareholders' offers to
purchase exceed the amount of Excess Offered Stock, the option to acquire such
Stock shall be allocated among the Other Shareholders desiring to purchase it as
follows:

(i)      Each Other Shareholder shall be absolutely entitled to acquire any
         number of shares of Excess Offered Stock that is equal to or less than
         their proportionate part of such Excess Offered Stock, based upon the
         number of shares owned by each Other Shareholder electing to acquire
         any of the Excess Offered Stock;

(ii)     Each Other Shareholder electing to acquire more than their
         proportionate part of the Excess Offered Stock under the previous
         allocation step may acquire a proportionate part of the remainder of
         the Excess Offered Stock that is not previously allocated to Other
         Shareholders, (i.e., because some acquiring Other Shareholders did not
         elect to acquire their entire ratable portion under the preceding
         allocation step), based upon the number of shares of Stock owned by
         each such acquiring Other Shareholder who has elected to acquire more
         than their proportionate part of the Excess Offered Stock;

(iii)    The allocation procedure described in Paragraph (ii) shall be repeated
         until all of the Excess Offered Stock has been allocated among all of
         the Other Shareholders electing to acquire such Excess Offered Stock
         and no such acquiring Other Shareholder has been allocated more than
         his proportionate share of the remaining Excess Offered Stock under the
         last such allocation step.

         If a husband and wife are both Shareholders, the Stock owned by each
such spouse shall be limited to the Stock actually registered in a spouse's name
plus one-half of the Stock registered in the joint names of both spouses for the
limited purpose of determining each Other Shareholder's proportionate part of
the Offered Stock.

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         If the Corporation and Other Shareholders have not given written notice
of election to acquire all of the Offered Stock within forty (40) days of the
First Refusal Notice Date, then between the forty-first and fiftieth day
following the First Refusal Notice Date the Corporation or any of the Other
Shareholders may give written notice to the Offeror Shareholder, to the
Corporation, and to the Other Shareholders of an election to purchase any or all
of the Offered Stock that the Corporation or Other Shareholders have not
previously agreed to purchase. Such additional shares of Stock shall be
allocated on a first-to-give notice basis determined as of the date written
notice is received by the Corporation.

         Section 3.04. REQUIREMENT TO PURCHASE ALL OFFERED STOCK.
Notwithstanding the provisions of the preceding Section 3.03, the options to
purchase shares of Stock described in the Notice of Right of First Refusal may
be exercised and the Closing consummated only if the Corporation and the Other
Shareholders collectively agree to purchase all of the shares of the Offered
Stock.

         Section 3.05. PURCHASE PRICE. The total purchase price (the "Purchase
Price") for all the Stock to be purchased pursuant to Article III will be the
total purchase price for the proposed Transfer, and upon the same terms and
conditions, as set forth in the Third Party Offer.

         Section 3.06. COMPLIANCE REQUIRED. Any Transfer described in this
Article III of a Shareholder's Stock without complying with the giving of a
Notice of Right of First Refusal and the Right of First Refusal provisions of
this Article III shall be void, and the Corporation shall issue a Notice of
Right of First Refusal upon discovery of such Transfer, a copy of which shall be
sent to the person or entity making such Transfer, his or her Transferee, the
Corporation, and all Shareholders. The duty of the Corporation to see to the
issuance of such Notice of Right of First Refusal shall not be considered to be
elective, but shall be mandatory. Upon the giving of the Notice of Right of
First Refusal, the time periods for the exercise of the options specified in
Sections 3.02 and 3.03 shall commence running. If a Notice of Right of First
Refusal had already been given to the Corporation, but the Corporation is
required to issue a new Notice of Right of First Refusal under this Section, the
prior Notice of Right of First Refusal shall have no effect and the time periods
under the Notice of Right of First Refusal issued by the Corporation shall
apply.

         Section 3.07. PERMITTED TRANSFERS. The following transfers of Stock
shall be Permitted Transfers that do not require the giving of a Notice of a
Right of First Refusal under this Article III. Notwithstanding any other
provisions of this Agreement, a transfer or disposition in the manner described
below shall be permitted: (i) a Transfer by will or intestate succession to such
Shareholder's executors, administrators, testamentary trustees, legatees or
beneficiaries, (ii) a Transfer in a public offering pursuant to an effective
registration statement under the Securities Act of 1933, as amended, or pursuant
to Rule 144 promulgated thereunder, (iii) a Transfer to one or more Related
Parties of such Shareholders and (iv) a Transfer in connection with the pledge
of Stock by ACC to Wells Fargo as described in Section 2.01 hereof or any action
taken in connection with such pledge. As used herein, the term "Related
Parties," with respect to any person or entity means: (a) any other person or
entity that directly or indirectly, through one or more intermediaries, has
control of or is controlled by, or is under common control with, the person or
entity specified; and (b) with respect to any Shareholder which is an
individual, a lineal descendent, sibling, lineal descendent of a sibling, in
each case whether by blood or adoption, parent, spouse, spouse of a lineal
descendent or lineal descendent of a sibling (collectively, "Family Members"),
or a trust for the benefit of one or more Family Members.

         Section 3.08. TRANSFER UNDER OTHER ARTICLES. Notwithstanding any other
provision of this Article III, a Transfer pursuant to the provisions of Article
VI shall be permitted without complying with the Right of First Refusal
provisions of this Article III.


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                                   ARTICLE IV

                      CLOSING AND PAYMENT OF PURCHASE PRICE
                      -------------------------------------

         Section 4.01. CLOSING DATE AND LOCATION. If no other Closing is set by
the article hereof applicable to a purchase or sale hereunder, the closing of
the purchase and sale of the shares of Stock (the "Closing") provided for in
this Agreement will be held 10:00 a.m. at the offices of the Corporation on the
thirtieth (30th) day following the giving of the last notice of election
indicating a sale and purchase is to be made under the terms of this Agreement,
or such other date and place as the parties may agree (the "Closing Date").

         Section 4.02. MANNER OF PAYMENT. At the Closing, the Shareholders
purchasing such shares of Stock will pay their respective portions of the cash
purchase price by a cashier's check drawn on a bank in Houston, Texas. The full
amount of the purchase price must be paid at the Closing, unless the terms of
sale permit otherwise, or the parties hereto agree to permit another method of
payment. At the Closing, the Offering Shareholder or other person or persons
holding such shares of Stock will duly execute and deliver the certificates
evidencing such shares of Stock to the purchaser, in proper form for transfer,
free and clear of all liens, adverse claims and encumbrances, except as
contained in this Agreement.

                                    ARTICLE V

                   PREEMPTIVE RIGHT AND FUTURE STOCK ISSUANCE
                   ------------------------------------------

         Section 5.01. PREEMPTIVE RIGHT. In the event the Corporation proposes
to issue or sell any new capital stock ("NEW STOCK" for purposes of this Section
5.01), it will give the Shareholders written notice of its intention, describing
the type of New Stock and the price and terms upon which the Corporation
proposes to issue or sell the New Stock. The Shareholders will have ten (10)
days from the date of receipt of such notice to agree to purchase their
respective pro rata percentage of the New Stock for the price and upon the terms
specified in the notice by giving written notice to the Corporation stating the
quantity of New Stock agreed to be purchased pursuant to the preemptive right
granted under this Section 5.01. The preemptive right granted under this Section
5.01 will expire upon the sale of any Stock by the Shareholders under this
Agreement or in the event that the Shareholders do not exercise their preemptive
right upon any issuance or sale of New Stock by the Corporation.

         Section 5.02. FUTURE STOCK ISSUANCE. The Corporation agrees that, as a
part of the consideration to be received for the issuance of any additional
Stock by the Corporation, the Corporation shall require the purchaser of such
Stock, and the spouse of such purchaser (if any), to assume all of the rights,
restrictions and obligations that are conferred and imposed upon the
Shareholders and their spouses pursuant to the terms of this Agreement, such
purchaser and his or her spouse to evidence their agreement to be so bound by
becoming signatory parties to this Agreement in their respective capacities as
Shareholder and spouse of a Shareholder. The Shareholders agree to enter into an
amendment to this Agreement providing that any such purchaser shall be deemed to
be a Shareholder of the Corporation, and that such purchaser's spouse shall be
deemed to be a spouse consenting to the terms of this Agreement. Prior to the


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issuance of any additional Stock of the Corporation, the Shareholders who are
parties to this Agreement shall be allowed to purchase any additional Stock to
be offered by the Corporation upon such terms as the Corporation may so offer in
order to maintain their pro rata ownership in the Corporation.

         Section 5.03.     RESTRICTED ACTIVITIES.

         (a)      ACC, Mortensen and JOS acknowledge that JOS has entered into
                  that certain Credit and Security Agreement with Wells Fargo,
                  whereby JOS has borrowed under certain term loans and
                  revolving credit loans from Wells Fargo ("Wells Fargo Debt").
                  ACC and Mortensen agree that, except for the initial Wells
                  Fargo Debt, JOS will not incur additional indebtedness in
                  excess of $500,000.00 without the written consent of
                  eighty-five percent (85%) of the outstanding Stock. It is also
                  acknowledged and agreed by ACC, Mortensen and JOS that the
                  proceeds from the Wells Fargo Debt will be loaned by JOS to
                  ACC as evidenced by that certain promissory note of even date
                  herewith from ACC to JOS.

         (b)      ACC, Mortensen and JOS acknowledge that JOS has loaned funds
                  to ACC pursuant to that promissory note (fixed rate) ("ACC
                  Note") of even date herewith. ACC, JOS and Mortensen agree
                  that except for the ACC Note, JOS will not make any additional
                  loans to ACC or any of its affiliates in excess of $500,000
                  without written consent of eighty-five percent (85%) of the
                  outstanding Stock.

                                   ARTICLE VI

             BRING-ALONG RIGHT, TAG-ALONG RIGHT AND MORTENSEN OPTION
             -------------------------------------------------------

         Section 6.01.     BRING-ALONG RIGHT.

                  (a) PROPOSED TRANSFER. If one or more Shareholders ("Sellers"
         for purposes of this Article VI) propose to Transfer (in a sale
         consummated in a single transfer or series of related transfers to a
         single purchaser or a group of purchaser as part of a single
         transaction or group of related transactions) Stock representing
         fifty-one percent (51%) or more of the then outstanding Stock (a
         "Transfer" for purposes of this Article VI), and provided that the
         Transfer is not an Permitted Transfer (as defined in Section 3.07
         hereof), then such Sellers shall have the right ("Bring-Along Right"),
         but not the obligation, to cause each of the Other Shareholders ("Other
         Shareholders" for purposes of this Article VI) to tender to the
         third-party offeror(s) ("Third Party") for purchase, at the same price
         per share of Stock and on the same terms of payment and conditions as
         apply to such Sellers, the Stock held by such Other Shareholders equal
         to the total number of shares of Stock held by such Other Shareholders
         multiplied by a fraction, the numerator of which is the number of
         shares of Stock the Sellers propose to themselves Transfer to the Third
         Party, and the denominator of which is the aggregate number of shares
         of Stock held by Sellers. A determination by the Sellers to exercise
         the Bring-Along Right shall be made based upon a written agreement to
         do so executed by Sellers holding at least fifty-one percent (51%) of
         the then outstanding Stock of the Corporation. In the event that
         Shareholders owning in the aggregate fifty- one percent (51%) or more
         of the outstanding Stock of the Corporation propose to Transfer such
         Stock, and exercise the Bring-Along Right under this Section, then the
         other provisions of this Agreement shall be suspended and inapplicable
         with regard to such Transfer except for the option by Mortensen as set
         forth in Section 6.03 hereof.

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<PAGE>

                  (b) BRING-ALONG NOTICE. If the Sellers elect to exercise their
         Bring-Along Right under this Article, then such Sellers shall notify
         the Corporation and the other Shareholders in writing ("Bring-Along
         Notice"). Each Bring-Along Notice shall set forth (i) the name of the
         Third Party to which the Sellers propose to Transfer Stock and the
         number of shares proposed to be transferred, (ii) the address of the
         Third Party, (iii) the proposed amount and form of consideration, and
         terms and conditions of payment offered by the Third Party ("Third
         Party Terms"), and (iv) that the Third Party has been informed of the
         rights provided for in this Article and has agreed to purchase Stock in
         accordance with the terms hereof. The Bring-Along Notice shall be given
         at least thirty (30) days prior to settlement of the proposed Transfer.

                  (c) CONSUMMATION. Except as otherwise provided in this
         Agreement, upon the giving of a Bring-Along Notice, each Other
         Shareholder shall be entitled and obligated to sell the Stock set forth
         therein to the Third Party on the Third Party Terms; neither the
         Sellers nor any Other Shareholder shall be obligated to consummate the
         sale of any Stock if the Third Party does not purchase all Stock which
         the Shareholders are entitled to sell pursuant thereto. Upon the giving
         of a Bring-Along Notice, Mortensen shall (i) either sell his shares as
         set forth in this Section 6.01, or (ii) exercise the option to convert
         his shares as set forth in Section 6.03 hereof, except that the one
         year time restriction shall not apply to his option under Section 6.03
         in the event of a Bring- Along Notice.

                  (d) SETTLEMENT. At the settlement of any Transfer pursuant to
         this Article, the Third Party shall remit to each Shareholder the
         consideration for the total sales price of the Stock of such
         Shareholders sold pursuant hereto, upon delivery by such Shareholder of
         certificate(s) for such Stock duly endorsed in blank for transfer or
         accompanied by stock power(s) duly executed in blank , and the
         compliance by such Shareholder with all other conditions to settlement
         generally applicable to the Sellers and all Other Shareholders selling
         Stock in such transaction (including the provision by the Other
         Shareholders to the Third Party of representations and warranties
         covering the same subject matter as those provided by the Sellers).

         Section 6.02      TAG-ALONG RIGHT.

                  (a) PROPOSED TRANSFER. If one or more Shareholders ("Sellers")
         propose to Transfer Stock representing fifty-one percent (51%) or more
         of the then outstanding Stock, and provided that the Transfer is not a
         Permitted Transfer (as defined in Section 3.07 hereof), then each of
         the Shareholders other than the Sellers ("Tag-Along Shareholders")
         shall have the right ("Tag-Along Right") to require the proposed
         purchaser(s) to purchase from such Tag-Along Shareholder up to the
         number of whole shares of Stock not to exceed the number derived by
         multiplying the total number of shares of Stock to be purchased by the
         proposed purchaser(s) in such transaction(s) by a fraction, the
         numerator of which is the total number of shares of Stock owned by such

                                       10
<PAGE>

         Tag- Along Shareholder, and the denominator of which is the total
         number of shares of Stock owned by the Sellers and all Tag-Along
         Shareholders. Any Stock purchased from Tag-Along Shareholders pursuant
         to this Section shall be paid for at the same price per share and upon
         the same terms of payment and conditions as such proposed Transfer by
         the Sellers ("Transfer Terms").

                  (b) TAG-ALONG NOTICE. The Sellers shall promptly notify the
         Tag-Along Shareholders in the event they propose to make a Transfer
         giving rise to Tag-Along Rights, and shall furnish the Tag-Along
         Shareholders with the Transfer Terms and a copy of any written offer or
         agreement pertaining thereto. The Tag-Along Right may be exercised by
         any Tag-Along Shareholder by delivery of a written notice to each
         Seller proposing to sell Stock ("Tag-Along Notice") within fifteen (15)
         days following such Tag-Along Shareholder's receipt of such notice from
         Sellers. The Tag-Along Notice shall state the number of shares of Stock
         that such Tag-Along Shareholder proposes to include in such Transfer to
         the proposed purchaser (not to exceed the number determined in
         accordance with Article 6.02(a) above). In the event that the proposed
         purchaser does not purchase the specified number of shares of Stock
         from the Tag-Along Shareholders on the Transfer Terms, and subject to
         the same terms and conditions as are applicable to the Sellers in such
         transaction, then the Sellers shall not be permitted to sell any shares
         of Stock to the proposed purchaser in the proposed Transfer.

                  (c) SETTLEMENT. At the settlement of any Transfer pursuant to
         this Article 6.02, the proposed purchaser shall remit to each selling
         Shareholder the consideration for the total sales price of the shares
         of Stock of such Shareholder sold pursuant hereto, upon delivery by
         such Shareholder of certificate(s) for such shares of Stock duly
         endorsed in blank for transfer or accompanied by stock power(s) duly
         executed in blank ,and the compliance by such Shareholder with all
         other conditions to settlement generally applicable to the Sellers and
         all other Tag-Along Shareholders selling shares of Stock in such
         transaction (including the provision by Tag-Along Shareholders to the
         proposed purchaser of representations and warranties covering the same
         subject matter as those provided by Sellers).

         Section 6.03 MORTENSEN OPTION. At the end of one (1) year from the date
of this Agreement, in the event that no sale of Stock has occurred by Mortensen
pursuant to this Agreement, Mortensen shall have the option ("OPTION"), at any
time after such time, to convert all his shares of Stock of the Corporation into
the common stock, $.15 par value ("ACC STOCK") of ACC. The Option to convert
Mortensen's Stock into ACC Stock shall be determined by multiplying (i) 4.6
times the trailing twelve months EBITDA (as defined below) of the Corporation as
determined in accordance with generally accepted accounting principles (ii) less
any net inter-company loans to the Corporation and third party investments in
the Corporation (iii) times nineteen percent (19%). The trailing twelve months
EBITDA will be determined by the Corporation's certified public accountants.
Mortensen shall give the Corporation and ACC written notice of his intention to
exercise the Option. Upon notice of exercise of the Option hereunder, ACC shall
calculate the conversion multiple within thirty (30) days of receipt of such
notice and the number shares of ACC Stock to be received by Mortensen shall be
based on the average closing bid price of ACC Stock for the preceding thirty
(30) days in which the ACC Stock was traded from the date of notice given by
Mortensen. ACC will immediately notify Mortensen of such calculation, and if


                                       11
<PAGE>

agreed to by Mortensen, the parties will proceed with the conversion at a
mutually agreeable date and place, which shall in no event be later than sixty
(60) days following the date Mortensen gave notice hereunder. In addition, in
the event that Mortensen is given a Bring Along Notice pursuant to Section 6.01
hereunder prior to exercise of the Option hereunder, the Option hereunder must
be exercised by Mortensen within thirty (30) days of receipt of the Bring Along
Notice, otherwise the Bring Along Notice will take precedence and the Option
hereunder will terminate.

         "EBITDA," for purposes of this Agreement, is defined as the
Corporation's earnings before interest, taxes, depreciation and amortization and
any payments made to ACC as parent company overhead.

                                   ARTICLE VII

                               REGISTRATION RIGHTS
                               -------------------

         Section 7.01.     DEMAND REGISTRATION.

                  (a) REQUEST. If ACC receives at any time after six (6) months
         from the date of this Agreement and within three (3) years thereafter,
         a written request from Mortensen that ACC file a registration statement
         under the Securities Act of 1933, as amended ("Securities Act")
         covering the registration of Mortensen's ACC Stock pursuant to this
         Section 7.01, then ACC will effect as soon as reasonable, within ten
         (10) business days after receipt of such written request, the
         registration under the Securities Act of all ACC Stock which Mortensen
         requests to be registered and included in such registration.

                  (b) UNDERWRITING. If Mortensen intends to distribute the ACC
         Stock covered by his request by means of an underwriting, then
         Mortensen will so advise ACC as a part of his request made pursuant to
         this Section 7.01. Mortensen will enter into an underwriting agreement
         in customary form with the managing underwriter or underwriters
         selected for such underwriting by ACC. Notwithstanding any other
         provision of this Section 7.01, if the underwriter(s) advise(s) ACC in
         writing that marketing factors require a limitation of the number of
         securities to be underwritten then ACC will so advise Mortensen, and
         the number of shares of ACC Stock that may be included in the
         underwriting will be reduced as required by the underwriter(s).

                  (c) MAXIMUM NUMBER OF DEMAND REGISTRATIONS. ACC is obligated
         to effect only one (1) such registration pursuant to this Section 7.01.

                  (d) DEFERRAL. Notwithstanding the foregoing, if ACC furnishes
         Mortensen a certificate signed by the Chief Executive Officer of ACC
         stating that in the good faith judgment of the Board of Directors of
         ACC , it would be seriously detrimental to ACC and its stockholders for
         such registration statement to be filed and it is therefore essential
         to defer the filing of such registration statement, then ACC will have
         the right to defer such filing for a period of not more than one
         hundred twenty (120) days after receipt of the request of Mortensen;
         provided, however, that ACC may not utilize this right more than once
         in any twelve (12) month period.

                                       12
<PAGE>

                  (e) EXPENSES. All expenses incurred in connection with the
         registration pursuant to this Section 7.01, including without
         limitation all registration and qualification fees, printers' and
         accounting fees, fees and disbursements of counsel for ACC and
         underwriters (but excluding underwriters' discounts and commissions),
         will be borne by Mortensen.

         Section 7.02. PIGGYBACK REGISTRATION. If following the exercise of the
Option by Mortensen, ACC at any time proposes to file on its behalf or on behalf
of any of its security holders a registration statement under the Securities Act
of 1933, as amended ( "Act") on any form (other than a registration statement on
Form S-3 or relating to any employee benefit plan or corporation reorganization)
for ACC Stock it will give written notice setting forth the terms of the
proposed offering at least thirty (30) days before the initial filing with the
Securities and Exchange Commission ("SEC") of such registration statement, and
offer to include in such filing such shares of ACC Stock as Mortensen may
request. Mortensen will advise the ACC in writing within ten (10) days after the
date of receipt of such notice from ACC, setting forth the amount of such shares
of ACC Stock for which registration is requested. ACC will thereupon include in
such filing the number of shares of ACC Stock for which registration is so
requested and will use its best efforts to effect registration under the Act of
such shares of ACC Stock. Notwithstanding the foregoing, if the managing
underwriter(s) of such offering deliver a written statement to ACC that the
success of the offering would be materially and adversely affected by inclusion
of the ACC Stock owned by Mortensen or other ACC stockholders requested to be
included, then the amount of securities to be offered for the accounts of
Mortensen and the other ACC stockholders will be reduced pro rata (according to
the securities requested to be included in registration) to the extent necessary
to reduce the total amount of securities to be included in such offering to the
amount recommended by such managing underwriter(s).

         7.03. FORM S-3 REGISTRATIONS. In addition to the registration rights
provided in Section 7.01 above, if at any time ACC is eligible to use Form S-3
(or any successor form) for registration of secondary sales of ACC Stock,
Mortensen may request in writing that the ACC register the shares of ACC Stock
owned by him on such form. Thereupon, the ACC will, as soon as practicable, use
its best efforts to effect the registration on Form S-3 of all securities that
ACC has so be requested to register by Mortensen for sale. ACC will use its best
efforts to qualify and maintain its qualification for eligibility to use Form
S-3 for such purpose.

                                  ARTICLE VIII

                                     NOTICES
                                     -------

         Section 8.01. NOTICE PROCEDURE. All notices required to be given
hereunder will be deemed to be duly given on the date of delivery if delivered
in person or three (3) Business Days after the date of mailing if mailed by
registered or certified mail, postage prepaid, return receipt requested, to the
Secretary of the Corporation and to the Shareholders at the addresses indicated
on the signature page of this Agreement. The address of any Shareholder may be
changed only by giving written notice of such change of address to all of the
other parties hereto in the manner provided herein for giving notices.

                                       13
<PAGE>

                                   ARTICLE IX

                                  STOCK LEGEND
                                  ------------

         Section 9.01. LEGEND REQUIRED BY THIS AGREEMENT. The Corporation and
each Shareholder hereby agrees that all certificates representing shares of
Stock of the Corporation that at any time are subject to the provisions of this
Agreement will have endorsed upon them, in addition to any legend required by
the Corporation's bylaws, in boldface type a legend in substantially the
following form:

         THE SHARES OF STOCK REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A
SHAREHOLDERS' AGREEMENT ("AGREEMENT"), DATED FEBRUARY 1, 2002, AMONG THE
SHAREHOLDERS, A COPY OF WHICH IS ON FILE AT THE PRINCIPAL OFFICE OF THE
CORPORATION, AND SAID SHARES MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED,
HYPOTHECATED, OR OTHERWISE DISPOSED OF EXCEPT IN STRICT ACCORDANCE WITH THE
TERMS OF THE AGREEMENT. A COPY OF THE AGREEMENT WILL BE FURNISHED WITHOUT CHARGE
TO THE HOLDER OF THIS CERTIFICATE UPON RECEIPT BY THE CORPORATION AT ITS
PRINCIPAL PLACE OF BUSINESS OR REGISTERED OFFICE OF A WRITTEN REQUEST FROM THE
HOLDER REQUESTING SUCH A COPY.

         Section 9.02. EXECUTION OF AGREEMENT BY TRANSFEREE. Under no
circumstances will any sale or other Transfer of any shares of Stock subject to
this Agreement be valid until the proposed transferee has executed and become a
party to an Agreement substantially similar to this Agreement and thereby
becomes subject to all of its provisions, unless this requirement is waived by
written consent of the parties; notwithstanding any other provisions of this
Agreement, no such sale or other Transfer of any kind will in any event result
in the nonapplicability of the provisions of this Agreement at any time to any
of the shares of Stock subject to this Agreement.

                                    ARTICLE X

                                      TERM
                                      ----

         Section 10.01. TERMINATION OF AGREEMENT. This Agreement will terminate
upon the earlier of: (a) the agreement of all parties hereto to terminate this
Agreement, (b) the purchase by the Corporation of all the shares of Stock of all
but one Shareholder, (c) the purchase by any one Shareholder of all of the
issued and outstanding shares of Stock of the Corporation, (d) upon the exercise
by Mortensen of the Option described in Section 6.03 and subsequent conversion
of his Stock for shares of ACC Stock, or (e) upon the dissolution of the
Corporation, or upon the filing of a voluntary or involuntary petition by or
against the Corporation under Chapter 7 or Chapter 11 of the Bankruptcy Code
upon the appointment of a receiver for the Corporation.

         Section 10.02. TERMINATION AS TO SPECIFIC SHAREHOLDER. This Agreement
shall terminate as to any specific Shareholder upon the date such Shareholder
ceases to own any Stock. Such Shareholder also shall cease to be a party to this
Agreement as of the date that he ceases to own, directly or beneficially, any
Stock.

                                       14
<PAGE>

                                   ARTICLE XI

                                  MISCELLANEOUS
                                  -------------

         Section 11.01. FURTHER ASSURANCES. Each party to this Agreement agrees
to perform all further acts and to execute and deliver all further documents
which may be reasonably necessary to carry out the provisions of this Agreement.

         Section 11.02. SEVERABILITY. In the event that any of the provisions,
or portions thereof, of this Agreement are held to be unenforceable or invalid
by an court of competent jurisdiction, the validity and enforceability of the
remaining provisions, or portions thereof, will not be affected, and in lieu of
such unenforceable provision there shall be added automatically as part of this
Agreement a provision as similar in terms as may be valid and enforceable.

         Section 11.03. CONSTRUCTION. Whenever used in this Agreement, the
singular number will include the plural, and the plural number will include the
singular; pronouns in the masculine, feminine, or neuter gender will include
each other gender.

         Section 11.04. GOVERNING LAW. This Agreement has been executed in and
will be governed by the laws of the State of Texas.

         Section 11.05. SUCCESSORS. Subject to the restrictions against Transfer
or assignment as contained in this Agreement, the provisions of this Agreement
will benefit and will be binding on the assigns, successors in interest,
personal representatives, estates, heirs and legatees of each of the parties
hereto. Each of the Shareholders agrees that he or she will not create or permit
to exist any lien, claim or encumbrance at any time on any of his or her shares
of stock subject to this Agreement, other than the encumbrance created by this
Agreement.

         Section 11.06. AMENDMENT. This Agreement may only be amended by the
written consent of all of the parties to this Agreement at the time of such
amendment.

         Section 11.07. HEADINGS. The section headings contained in this
Agreement are for convenience only and shall in no manner be construed as part
of this Agreement.

         Section 11.08. TREASURY STOCK. If any Stock that is held as treasury
stock of the Corporation is transferred pursuant to a foreclosure, the
Transferee of such transaction shall hold the Stock subject to all of the
provisions of this Agreement as if such Transferee were a "Shareholder" as that
term is used herein.

         Section 11.09. ENTIRE AGREEMENT: COUNTERPARTS. This Agreement contains
the entire understanding between the parties concerning the subject matter
contained in this Agreement. There are no representations, agreements,
arrangements or understandings, oral or written, between or among the parties
hereto, relating to the subject matter of this Agreement, which are not fully
expressed herein. This Agreement may be signed in one or more counterparts, all
of which shall be considered one and the same agreement.

                                       15
<PAGE>

         Section 11.10. INSURANCE. The Corporation may desire to acquire
insurance on the lives of any one or more Shareholders in order to provide funds
for its commitment to purchase Stock in the event of a Shareholder's death. Each
Shareholder agrees to cooperate with the Corporation in this endeavor and to
assist it to the extent required in order to allow it to obtain such insurance.

         Section 11.11. WAIVER. The waiver by any party hereto of a breach of
any provision of this Agreement shall not operate or be construed as a waiver of
any subsequent breach by an party.

         Section 11.12. SPECIFIC PERFORMANCE. The right to own and vote Stock
and to restrict the transfer of the Stock is hereby declared by the parties
hereto to be a unique right, the loss of which is not readily susceptible to
monetary quantification. Consequently, the parties hereto agree that an action
for specific performance of the purchase and sale obligations created by this
Agreement or an action brought to enjoin the unauthorized transfer of Stock are
remedies for the breach of the provisions of this Agreement. If the parties to
this Agreement are forced to institute legal proceedings to enforce their rights
in accordance with the provisions of this Agreement, they shall be entitled to
recover their reasonable attorneys' fees and court costs incurred in enforcing
such rights.

         Section 11.13. BUSINESS DAYS. Whenever the terms of this Agreement call
for the performance of a specific act on a specified date, which date falls on a
Saturday, Sunday or legal holiday, the date for the performance of such act
shall be postponed to the next succeeding regular Business Day following such
Saturday, Sunday or legal holiday.

         Section 11.14. COMMUNITY PROPERTY INTERESTS. The parties hereto
acknowledge that a spouse of a Shareholder may own a community property interest
in the Stock of a spouse, but the parties hereto hereby agree that the term
"Shareholder" shall apply only to the named individual parties to this
Agreement, and shall not apply to the spouse of any such party.

         IN WITNESS WHEREOF, the parties hereto have entered into this Agreement
to be effective as of the date first written above.

                                       JENS OILFIELD SERVICES, INC.


                                       By: /S/ MUNAWAR H. HIDAYATALLAH
                                          --------------------------------------
                                            Munawar H. Hidayatallah,
                                            Chairman and Chief Executive Officer
                                            8150 Lawndale
                                            Houston, Texas 77012

                                       16
<PAGE>


SHAREHOLDER:                       ALLIS-CHALMERS CORPORATION


                                   By: /S/ MUNAWAR H. HIDAYATALLAH
                                      ----------------------------------------
                                        Munawar H. Hidayatallah,
                                        Chief Executive Officer
                                        8150 Lawndale
                                        Houston, Texas 77012

                                        Owner of ______ Shares





SHAREHOLDER:                       By: /S/ JENS H. MORTENSEN, JR.
                                      ----------------------------------------
                                        Jens H. Mortensen, Jr.
                                        12301 Rooth Road
                                        McAllen, Texas 78504

                                        Owner of ______ Shares



                                   By: /S/ TAMMI MORTENSEN
                                      ----------------------------------------
                                        [Spouse of Jens H. Mortensen, Jr.]
                                        --------------------------------------
                                                     [Name Printed]

                                       17