<PAGE>

                                                                   EXHIBIT 10.27

                              FORBEARANCE AGREEMENT
                     AND FIRST AMENDMENT TO CREDIT AGREEMENT


         This Agreement is entered into and effective as of March 21, 2003, by
and between JENS' OIL FIELD SERVICE, INC., a Texas corporation (the "Borrower")
and WELLS FARGO CREDIT, INC., a Minnesota corporation (the "Lender").

                                    RECITALS

         The Borrower and Lender entered into a Credit and Security Agreement
dated as of February 1, 2002 (the "Credit Agreement"). Capitalized terms used
but not defined herein shall have the meanings given them in the Credit
Agreement.

         Pursuant to the Credit Agreement, the Lender has made a Term Advance to
the Borrower in the amount of $4,042,396, has made a Real Estate Advance to the
Borrower in the amount of $532,000, and has committed to make revolving Advances
to the Borrower not to exceed $1,000,000. The principal balance of all of the
loans, together with accrued and unpaid interest thereon, and fees and
reimbursable expenses in connection with the foregoing (collectively, the
"Indebtedness") are secured by substantially all of the assets of the Borrower
pursuant to the terms of the Credit Agreement.

         The Borrower is in default of the following provisions under the Credit
Agreement (collectively, the "Designated Defaults"): Section 6.7(b); Section
6.12(b) for June 30, 2002 and September 30, 2002; Section 7.10; and Sections
8.1(p) and 8.1(q) as a result of defaults in existence as of the date of this
Agreement under the Strata Credit Agreement and the Borrower's agreements with
Energy Group and Energy Capital. At no time has the Lender waived the Designated
Defaults.

         As a result of the Designated Defaults, the Lender has the unrestricted
right to declare the Indebtedness immediately due and payable and to exercise
its rights and remedies with respect to the collateral for such Indebtedness.
The Borrower has requested that the Lender forbear from exercising its remedies
under the Credit Agreement, and the Lender is willing to do so on the terms and
conditions set forth in this Agreement.

         NOW THEREFORE, in consideration of the premises and the mutual promises
herein contained, the parties hereto agree as follows:

         1. DEFINED TERMS. Capitalized terms used in this Agreement which are
defined in the Credit Agreement shall have the same meanings as defined therein,
unless otherwise defined herein.

         2. AGREEMENT TO FORBEAR. The Lender agrees that during the period from
the date hereof to and including the earlier of (i) June 30, 2003 or (ii) the
date on which a Forbearance Default occurs (the "Forbearance Period"), the
Lender will not demand payment of, accelerate the maturity of or otherwise
initiate collection action with respect to the Indebtedness, and will not
implement the Default Rate of interest.

<PAGE>

         3. FORBEARANCE DEFAULTS. "Forbearance Default" means any of the
following:

                  (a) a Default or an Event of Default, other than (i) a
         Designated Default or (ii) a breach of the financial covenants in
         Section 6.12(b) of the Credit Agreement;

                  (b) payment by the Borrower on any debt subject to a
         Subordination Agreement; provided, however, that so long as no
         Forbearance Default has occurred or would occur immediately after or as
         a result of such payment, the Borrower may pay regular monthly interest
         payments to Wells Fargo Energy Capital in an amount not to exceed
         $30,000 per month in the aggregate (but the Borrower may not pay any
         unpaid amounts that were due prior to January 1, 2003);

                  (c) payment by the Borrower of any dividends or distributions
         to shareholders; provided, however, that so long as no Forbearance
         Default has occurred or would occur immediately after or as a result of
         such distribution, and after providing evidence of such expenses
         acceptable to the Lender in its sole discretion, the Borrower may (i)
         make monthly distributions of up to $25,000 for the purpose of paying
         corporate expenses incurred by Allis-Chalmers, and (ii) make a one-time
         distribution to Allis- Chalmers of up to $300,000 to pay for corporate
         franchise taxes, preparation of a proxy statement and annual report,
         legal and accounting costs for the audit of the Borrower's financial
         statements for its fiscal year ended December 31, 2002, and necessary
         filings with the Securities and Exchange Commission;

                  (d) the Borrower shall have less than $250,000 in Availability
         at any time; or

                  (e) a Forbearance Default shall occur under the Forbearance
         Agreement and Second Amendment to Amended and Restated Credit
         Agreement, of even date herewith, by and between the Lender and Strata.

         4.       AMENDMENTS TO CREDIT AGREEMENT.

                  (a) Section 1.1 of the Credit Agreement is amended by adding
         or amending, as the case may be, the following definitions:

                  "Revolving Floating Rate" means an annual rate equal to the
         sum of the Base Rate plus three percent (3.0%), which annual rate shall
         change when and as the Base Rate changes.

                  "Term Floating Rate" means an annual rate equal to the sum of
         the Base Rate plus three percent (3.0%), which annual rate shall change
         when and as the Base Rate changes.

                  (b) Section 6.12(a) of the Credit Agreement is hereby amended
         in its entirety to read as follows:

                           "(a) Borrower will maintain, for each period
                  described below, its Debt Service Coverage Ratio at not less
                  than the amount set forth opposite such period:

                                       2
<PAGE>

                                                          MINIMUM DEBT SERVICE
                        PERIOD                               COVERAGE RATIO
                        ------                               --------------

          Three months ending March 31, 2003                   0.90 to 1

           Six months ending June 30, 2003                     1.30 to 1"

                   (c) Section 6.13 of the Credit Agreement is hereby amended in
         its entirety to read as follows:

                  "Section 6.13 Minimum Period-to-Date Net Income. Borrower will
         achieve, as of each period described below, Net Income of not less than
         the amount set forth opposite such period:

                                                        MINIMUM PERIOD-TO-DATE
             PERIOD                                           NET INCOME
             ------                                           ----------
Month ending January 31, 2003                                  $155,000
Two months ending February 28, 2003                            $270,000
Three months ending March 31, 2003                             $410,000
Four months ending April 30, 2003                              $560,000
Five months ending May 31, 2003                                $700,000
Six months ending June 30, 2003                               $845,000"

                  (d) Section 7.10 of the Credit Agreement is hereby amended in
         its entirety to read as follows:

                           "Section 7.10 Capital Expenditures. The Borrower will
                  not incur or contract to incur Capital Expenditures of more
                  than $100,000 in the aggregate during the Borrower's fiscal
                  year ending December 31, 2003; provided, however, that in
                  addition to the foregoing, the Borrower may incur Capital
                  Expenditures of up to $300,000 for purchase of Equipment to be
                  used in Mexico during such fiscal year; and provided further
                  that upon receipt of cash proceeds under the Borrower's
                  existing insurance claim for Mexican equipment, the Borrower
                  may incur additional Capital Expenditures up to the amount of
                  such insurance proceeds actually received, but not in excess
                  of $200,000."

         5. BORROWER ACKNOWLEDGMENTS. By signing this Agreement, the Borrower
acknowledges and agrees that the Designated Defaults currently exist on the part
of the Borrower under the Credit Agreement and that as a result of such
Designated Defaults, the Lender could, in the absence of the Lender's agreement
to forbear as set forth in this Agreement, in its sole discretion, demand
immediate payment or otherwise take collection action with respect to the
Indebtedness. The Borrower further acknowledges and agrees that the Indebtedness
is the valid and enforceable obligation of the Borrower and is not subject to
any defenses or rights of set off of any kind or nature and that all of the
Indebtedness is secured by a valid and perfected lien in the Collateral.

         6. FORBEARANCE AND AMENDMENT FEE. The Borrower shall pay to the Lender,
as of the date hereof, a fully earned, non-refundable fee of $10,000 in
consideration of the Lender's execution of this Agreement.

                                       3
<PAGE>

         7. CONDITIONS PRECEDENT. This Agreement shall be effective when the
Lender shall have received an executed original hereof, together with each of
the following, each in substance and form acceptable to the Lender in its sole
discretion:

                  (a) A certificate of the Secretary or Assistant Secretary of
         the Borrower certifying as to (i) the resolutions adopted by the
         Borrower's directors with respect to this Agreement; (ii) the continued
         authorization of the Borrower's officers and agents previously
         certified to the Lender; and (iii) the fact that the articles of
         incorporation and bylaws of the Borrower have not been amended since
         such documents were last certified to the Lender.

                  (b) The Acknowledgment and Agreement of Guarantors set forth
         at the end of this Agreement, duly executed by the Guarantors.

                  (c) Payment of the fee set forth in paragraph 7.

                  (d) Projections showing expected revenues, expenses, cash
         flows, borrowing base, and other financial information, on a monthly
         basis through the end of the Forbearance Period, showing the Borrower's
         ability to meet its cash needs through such period.

         8. REPRESENTATIONS AND WARRANTIES. The Borrower hereby represents and
warrants to the Lender as follows:

                  (a) The Borrower has all requisite power and authority to
         execute this Agreement and to perform all of its obligations hereunder,
         and this Agreement has been duly executed and delivered by the Borrower
         and constitutes the legal, valid and binding obligation of the
         Borrower, enforceable in accordance with its terms.

                  (b) The execution, delivery and performance by the Borrower of
         this Agreement have been duly authorized by all necessary corporate
         action and do not (i) require any authorization, consent or approval by
         any governmental department, commission, board, bureau, agency or
         instrumentality, domestic or foreign, (ii) violate any provision of any
         law, rule or regulation or of any order, writ, injunction or decree
         presently in effect, having applicability to the Borrower, or the
         articles of incorporation or by-laws of the Borrower, or (iii) result
         in a breach of or constitute a default under any indenture or loan or
         credit agreement or any other agreement, lease or instrument to which
         the Borrower is a party or by which it or its properties may be bound
         or affected.

                  (c) All of the representations and warranties contained in
         Article V of the Credit Agreement are correct on and as of the date
         hereof as though made on and as of such date.

         9. NO WAIVER. The execution of this Agreement and acceptance of any
documents related hereto shall not be deemed to be a waiver of any Default or
Event of Default under the Credit Agreement or breach, default or event of
default under any Security Document or other document held by the Lender,
whether or not known to either Lender and whether or not existing on the date of
this Agreement.

                                       4
<PAGE>

         10. RELEASE. The Borrower, and each Guarantor by signing the
Acknowledgment and Agreement of Guarantors set forth below, each hereby
absolutely and unconditionally releases and forever discharges the Lender, and
any and all participants, parent corporations, subsidiary corporations,
affiliated corporations, insurers, indemnitors, successors and assigns thereof,
together with all of the present and former directors, officers, agents and
employees of any of the foregoing, from any and all known claims, demands or
causes of action of any kind, nature or description arising out of or relating
in any way to this Agreement, the Credit Agreement, or the other Loan Documents,
whether arising in law or equity or upon contract or tort or under any state or
federal law or otherwise, which the Borrower or such Guarantor has had, now has
or has made claim to have against any such person for or by reason of any act,
omission, matter, cause or thing whatsoever arising from the beginning of time
to and including the date of this Agreement, whether such claims, demands and
causes of action are matured or unmatured.

         11. COSTS AND EXPENSES. The Borrower hereby reaffirms its agreement
under the Credit Agreement to pay or reimburse the Lender on demand for all
costs and expenses incurred by Lender in connection with the Credit Agreement,
the Security Documents and all other documents contemplated thereby, including
without limitation all reasonable fees and disbursements of legal counsel.
Without limiting the generality of the foregoing, the Borrower specifically
agrees to pay all fees and disbursements of counsel to the Lender for the
services performed by such counsel in connection with the preparation of this
Agreement and the documents and instruments incidental hereto. The Borrower
hereby agrees that the Lender may, at any time or from time to time in its sole
discretion and without further authorization by the Borrower, make a loan to the
Borrower under the Credit Agreement, or apply the proceeds of any loan, for the
purpose of paying any such fees, disbursements, costs and expenses.

         12. MISCELLANEOUS. This Agreement shall be governed by and interpreted
in accordance with the laws of the State of Minnesota. In any action brought or
arising out of this Agreement, the Borrower hereby consents to the sole
jurisdiction of any federal or state court having proper venue within the State
of Minnesota and also consents to the service of process by any means authorized
by Minnesota law. The headings used in this Agreement are for convenience only
and shall be disregarded in interpreting the substantive provisions of this
Agreement. Except as expressly provided otherwise herein, all terms used herein
shall have the meaning given to them in the applicable Credit Agreement. If any
provision of this Agreement shall be determined by a court of competent
jurisdiction to be invalid, illegal or unenforceable, that portion shall be
deemed severed therefrom, and the remaining parts shall remain in full force as
though the invalid, illegal or unenforceable portion had never been a part
hereof. This Agreement, together with the Credit Agreement and the other
agreements and documents referred to therein, including all amendments thereto,
comprises the complete and integrated agreement of the parties on the subject
matter hereof. This Agreement shall not be modified except by written instrument
executed by the Borrower and the Lender. This Agreement may be executed in any
number of counterparts, each of which when so executed and delivered shall be
deemed an original and all of which counterparts, taken together, shall
constitute one and the same instrument.

                                       5
<PAGE>


         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the day and year first above written.


                                       JENS' OIL FIELD SERVICE, INC.

                                       By  /S/ MUNAWAR HIDAYATALLAH
                                           ------------------------
                                       Its   Chief Executive Officer


                                       WELLS FARGO CREDIT, INC.

                                       By  /S/ MICHELLE SALISBURY
                                           ----------------------
                                           Michelle Salisbury, Vice President


                                       6
<PAGE>

                   ACKNOWLEDGMENT AND AGREEMENT OF GUARANTORS

         The undersigned, each a guarantor of the indebtedness of Jens' Oil
Field Service, Inc. (the "Borrower") to Wells Fargo Credit, Inc. (the "Lender")
pursuant to a separate Guaranty each dated as of February 1, 2002 (each, a
"Guaranty"), hereby (i) acknowledges receipt of the foregoing Agreement; (ii)
consents to the terms (including without limitation the release set forth in
paragraph 10 of the Agreement) and execution thereof; (iii) reaffirms his or its
obligations to the Lender pursuant to the terms of his or its Guaranty; and (iv)
acknowledges that the Lender may amend, restate, extend, renew or otherwise
modify the Credit Agreement and any indebtedness or agreement of the Borrower,
or enter into any agreement or extend additional or other credit accommodations,
without notifying or obtaining the consent of the undersigned and without
impairing the liability of the undersigned under his or its Guaranty for all of
the Borrower's present and future indebtedness to the Lender.



                                         ALLIS-CHALMERS CORPORATION

                                         By  /S/ MUNAWAR HIDAYATALLAH
                                             ------------------------
                                         Its   Chief Executive Officer


                                         WELLS FARGO CREDIT, INC.

                                         By  /S/ MICHELLE SALISBURY
                                             ----------------------
                                             Michelle Salisbury, Vice President



                                       7