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                                                                   EXHIBIT 10.24

                       FIFTH AMENDMENT TO CREDIT AGREEMENT

         THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (as same may be renewed,
extended, modified, restated amended and/or rearranged, the "Fifth Amendment")
dated as of August 6, 2002, is between MOUNTAIN COMPRESSED AIR, INC., a Texas
corporation (hereinafter referred to as "Borrower") and WELLS FARGO BANK TEXAS,
NATIONAL ASSOCIATION, a national banking association ("Bank").

                                    RECITALS:

         A. Bank and Borrower entered into that certain Credit Agreement dated
as of February 6, 2001 (the "Original Agreement"), as amended by that certain
First Amendment to Credit Agreement dated as of August 9, 2001 (the "First
Amendment"), as amended by that certain Second Amendment to Credit Agreement
dated as of November 30, 2001 (the "Second Amendment"), as amended by that
certain Third Amendment to Credit Agreement dated as of January 31, 2002 (the
"Third Amendment"), as amended by that certain Fourth Amendment to Credit
Agreement dated as of April 30, 2002 (the "Fourth Amendment", together with the
Original Agreement, the First Amendment, the Second Amendment, and the Third
Amendment referred to hereafter as the Agreement).

         B. OilQuip Rentals, Inc., a Delaware corporation (the "Parent")
("OilQuip"), Munawar and Jayne Hidayatallah (the "Hidayatallahs") and
Allis-Chalmers Company, a Delaware corporation ("Allis-Chalmers") each
guaranteed to the Bank the payment and performance of certain indebtedness and
obligations of Borrower to Bank.

         C. Borrower and Bank now desire to enter into this Fifth Amendment on
the terms set forth herein.

         NOW, THEREFORE, in consideration of the premises herein contained and
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto agree as follows:

                                    ARTICLE 1

                                  GENERAL TERMS

         Section 1.1 TERMS DEFINED IN AGREEMENT. As used in this Fifth
Amendment, except as may otherwise be provided herein, all capitalized terms
which are defined in the Agreement, as amended, have the same meaning herein as
therein, all of such terms and their definitions being incorporated herein by
reference.

         Section 1.2 CONFIRMATION AND EXTENT OF CHANGES. All terms which are
defined or referred to in the Agreement shall remain unchanged except as
otherwise specifically provided in this Fifth Amendment. It is hereby confirmed
that the term "Agreement" includes the Agreement as amended by this Fifth
Amendment.

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                                    ARTICLE 2

                                   AMENDMENTS

         Section 2.1 AMENDMENT TO SECTION 1.1(f). Effective as of the date
hereof, Section 1.1(f) of the Agreement is hereby amended to read in its
entirety as follows:

                  "(f) CASH COLLATERAL ACCOUNT. Borrower shall maintain with
         Bank, and Borrower has heretofore granted and hereby grants to Bank a
         security interest in, a non-interest bearing deposit account (Account
         No. 4496863051 maintained at Wells Fargo Bank N.A.) over which Borrower
         shall have no control ("Cash Collateral Account") and into which the
         proceeds of all Borrower's accounts and other rights to payment in
         which Bank has a security interest shall be deposited immediately upon
         their receipt by Borrower, whether before or after an Event of Default.
         Bank shall, and Borrower hereby authorizes Bank to, apply all such
         proceeds immediately upon their receipt by Bank as a principal
         reduction on the Line of Credit, and the balance, if any, as an
         interest reduction on the Line of Credit."

         Section 2.2 AMENDMENT TO SECTION 1.5. Effective as of the date hereof,
Section 1.5 of the Agreement is hereby amended to read in its entirety as
follows:

                  "SECTION 1.5 COLLECTION OF PAYMENTS. Borrower authorizes Bank
         to collect all principal, interest, and fees due under each credit
         subject hereto by charging Borrower's deposit account number 4496857319
         with Bank Borrower's cash collateral account number 4496863051 with
         Wells Fargo Bank N.A., or any other deposit account maintained by
         Borrower with Bank or with Wells Fargo Bank N.A., for the full amount
         thereof. Should there be insufficient funds in any such deposit account
         to pay all such sums when due, the full amount of such deficiency shall
         be immediately due and payable by Borrower."

         Section 2.3 AMENDMENT TO SECTION 3.2(b). Effective as of the date
hereof, Section 3.2(b) of the Agreement is hereby amended to read in its
entirety as follows:

                  "(b) DOCUMENTATION. Bank shall have received a Borrowing Base
Report in form and substance satisfactory to Bank, as well as all additional
documents which may be required in connection with such extension of credit."

         Section 2.3 AMENDMENT TO SECTION 4.3. Effective as of the date hereof,
Section 4.3 of the Agreement is hereby amended to read in its entirety as
follows:

         "SECTION 4.3 FINANCIAL STATEMENTS. Provide or cause to be provided to
Bank all of the following, in form and detail satisfactory to Bank:

                  (a) not later than 90 days after and as of the end of each
         fiscal year, an audited financial statement of Borrower, prepared by a
         recognized independent accounting firm acceptable to Bank, to include
         consolidated balance sheets and consolidated statements of income,
         retained earnings and cash flow, in accordance with generally accepted
         accounting principles, together with an unqualified opinion and such
         firm's covenant compliance calculations, certified by a senior
         financial officer;

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                  (b) not later than 30 days after and as of the end of each
         calendar month, a financial statement of Borrower, prepared by
         Borrower, to include consolidated balance sheets and consolidated
         statements of income, retained earnings and cash flow, in accordance
         with generally accepted accounting principles, together with covenant
         compliance calculations, certified by a senior financial officer;

                  (c) not later than 25 days after and as of the end of each
         calendar month, a borrowing base certificate attached hereto as
         Schedule I, an aged listing of accounts receivable and accounts
         payable, and a reconciliation of accounts, and not later than 25 days
         after and as of each calendar month, a list of the names and addresses
         of all Borrower's account debtors; all of which Borrower shall deliver
         to Wells Fargo Bank Texas, National Association, 1000 Louisiana, 3rd
         Floor, Houston, Texas 77002, Attn: Scott Gildea;

                  (d) not later than 30 days after and as of the end of each
         calendar month, a financial statement of Allis-Chalmers, prepared by
         and certified by a senior financial officer of Allis-Chalmers, to
         include consolidated balance sheets and consolidated statements of
         income, retained earnings and cash flow, in accordance with generally
         accepted accounting principles;

                  (e) not later than 90 days after each calendar year, the
         financial statements of Munawar Hidayatallah and Jayne Hidayatallah,
         signed and certified to the Bank on Bank's form and such individuals'
         income tax returns for such year;

                  (f) contemporaneously with each annual and monthly financial
         statement of Borrower required hereby, a certificate of a senior
         financial officer of Borrower that said financial statements are
         accurate, showing the calculations confirming Borrower's compliance
         with all financial covenants and that there exists no Event of Default
         nor any condition, act or event which with the giving of notice or the
         passage of time or both would constitute an Event of Default;

                  (g) not later than ninety (90) days after and as of the end of
         each fiscal year, audited consolidated and unaudited consolidating
         financial statements of Allis-Chalmers, prepared by a recognized
         independent accounting firm acceptable to Bank, to include consolidated
         balance sheets and consolidated statements of income, retained earnings
         and cash flow, in accordance with generally accepted accounting
         principles; and

                  (h) from time to time such other information as Bank may
         reasonably request."

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         Section 2.4 ADDITION OF SECTION 6.1(n). Effective as of the date
hereof, Section 6.1(n) shall be added to the Agreement immediately following
Section 6.1(m) thereof and shall read in its entirety as follows:

                  "(n) Any default in the payment and performance of any
         obligation or any defined event of default under the terms of any
         document or instrument executed by any of you (or by Strata Directional
         Technology, Inc., and/or Jens Oil Field Services, Inc.) and Wells Fargo
         Credit, Inc., Wells Fargo Equipment Finance, Inc., Wells Fargo Energy
         Capital, Inc., and/or us including, without limitation, that certain:
         (i) Credit Agreement by and between Borrower and Wells Fargo Energy
         Capital, Inc., dated as of February 6, 2001; and any amendment,
         modification, and/or supplement thereof; (ii) Master Lease dated as of
         December 31, 2001, between Borrower and Wells Fargo Equipment Finance,
         Inc., and any amendments, modifications, and/or supplements thereof;
         (iii) Credit and Security Agreement by and between Jens' Oil Field
         Service, Inc. and Wells Fargo Credit, Inc., dated as of February 1,
         2002, and any amendment, modification, and/or supplement thereof; and
         (iv) Credit and Security Agreement by and between Strata Directional
         Technology, Inc. and Wells Fargo Credit, Inc., dated as of February 1,
         2002, and any amendment, modification, and/or supplement thereof."

         Section 2.4 ADDITION OF SECTION 6.1(O). Effective as of the date
hereof, Section 6.1(o) shall be added to the Agreement immediately following
Section 6.1(n) thereof and shall read in its entirety as follow:

                  "(o) If Borrower shall fail to deliver a Subordination
         Agreement in form and substance satisfactory to Bank, executed by
         Munawar and Jayne Hidayatallah, Jens H. Mortensen, Bank, and Wells
         Fargo Credit, Inc., on or before August 16, 2002."

                                    ARTICLE 3

                         REPRESENTATIONS AND WARRANTIES

         In order to induce the Bank to enter into this Fifth Amendment and to
continue to make the loans provided for in the Agreement, the Borrower
represents and warrants (which representations and warranties will survive the
execution and delivery hereof and will be deemed for all purposes to be
additional representations and warranties of the Agreement) that:

         Section 3.1 REPRESENTATIONS AND WARRANTIES OF THE AGREEMENT AND THE
LOAN DOCUMENTS. The representations and warranties of the Borrower contained in
the Agreement and the Loan Documents and otherwise made in writing by or on
behalf of the Borrower pursuant to the Agreement and the Loan Documents were
true and correct when made, and are true and correct in all material respects at
and as of the time of delivery of this Fifth Amendment, except for such changes
in the facts represented and warranted as are not in violation of the Agreement
and the Loan Documents.

         Section 3.2 COMPLIANCE WITH OBLIGATIONS. The Borrower has performed and
complied with all agreements and conditions contained in the Agreement and the
Loan Documents required to be performed or complied with by the Borrower prior
to or at the time of delivery of this Fifth Amendment.

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         Section 3.3 DEFAULTS. There exists, and after giving effect to this
Fifth Amendment, will exist, no default or Event of Default, or any condition,
or act which constitutes, or with notice or lapse of time (or both) would
constitute an event of default under any loan agreement, note agreement, or
trust indenture to which the Borrower is a party.

         Section 3.4 NO AMENDMENTS. Nothing in Article 3 of this Fifth Amendment
is intended to amend any of the representations or warranties of the Agreement.

                                    ARTICLE 4

                                   CONDITIONS

         The Bank has relied upon the representations and warranties contained
in this Fifth Amendment in agreeing to the amendments and supplements to the
Agreement set forth herein and the amendments and supplements to the Agreement
set forth herein are conditioned upon and subject to the accuracy of each and
every representation and warranty of the Borrower made or referred to herein, to
the performance by the Borrower of its obligations to be performed under the
Agreement and the Loan Documents on or before the date of this Fifth Amendment
and to the following further conditions:

         Section 4.1 OFFICERS' CERTIFICATE. The Bank shall have received a
certificate of the officers of the Borrower setting forth (i) resolutions of its
board of directors in form and substance satisfactory to the Bank authorizing
the Borrower (and such other parties as may be required by Bank) to execute the
Loan Documents to which it is a party, and (ii) specimen signatures of the
officers so authorized.

         Section 4.2 ADDITIONAL DOCUMENTATION. The Borrower shall deliver to the
Bank such additional approvals, opinions, consents, security agreements,
supplemental security agreements, or documents as Bank may require.

                                    ARTICLE 5

                                  MISCELLANEOUS

         Section 5.1 LOAN DOCUMENTS. All Loan Documents shall secure the
indebtedness and obligations previously secured by such Loan Documents, as such
indebtedness and obligations are affected by this Fifth Amendment, whether or
not such Loan Documents shall be expressly amended or supplemented in connection
with this Fifth Amendment.

         Section 5.2 EXTENT OF AMENDMENTS. Except as otherwise expressly
provided herein, the Agreement, the Loan Documents, the Line of Credit and the
other instruments and agreements referred to therein are not amended, modified
or affected by this Fifth Amendment.

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         Section 5.3 EFFECTIVE DATE. Except as otherwise expressly provided
herein, the effective date of all provisions of this Fifth Amendment shall be
the date of execution indicated below.

         Section 5.4 TITLES OF ARTICLES, SECTIONS AND SUBSECTIONS. All titles or
headings to articles, sections, subsections or other divisions of this Fifth
Amendment are only for the convenience of the parties and shall not be construed
to have any effect or meaning with respect to the other content of such
articles, sections, subsections, or other divisions, such other content being
controlling as to the Agreement among the parties hereto.

         Section 5.5 COUNTERPARTS. This Fifth Amendment may be executed in two
or more counterparts. It will not be necessary that the signatures of all
parties hereto be contained on any one counterpart hereof; each counterpart
shall be deemed an original, but all of which together shall constitute one and
the same instrument.

         Section 5.6 FEES AND EXPENSES. Borrower will pay all fees and expenses
incurred by Bank in connection with this Agreement and the transactions
contemplated herein including, without limitation filing fees, search fees, and
reasonable attorneys' fees.

         Section 5.7 ENTIRE AGREEMENT. THIS FIFTH AMENDMENT AND ALL OTHER
INSTRUMENTS, DOCUMENTS, AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH
THIS FIFTH AMENDMENT EMBODY THE FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO
WITH RESPECT TO THE SUBJECT MATTER HEREOF AND THEREOF AND SUPERSEDE ANY AND ALL
PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS AND UNDERSTANDINGS, WHETHER
WRITTEN OR ORAL, RELATING TO THIS FIFTH AMENDMENT AND THE OTHER INSTRUMENTS,
DOCUMENTS AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS FIFTH
AMENDMENT, AND MAY NOT BE CONTRADICTED OR VARIED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OR DISCUSSIONS OF THE PARTIES
HERETO. THERE ARE NO ORAL AGREEMENTS AMONG THE PARTIES HERETO.

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<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this instrument to
be duly executed as of the 6 day of August 2002.

                                           BORROWER:

                                           MOUNTAIN COMPRESSED AIR, INC.


                                           By:   /s/ THEODORE F. POUND, III
                                                 ------------------------------
                                                 Theodore F. Pound, III
                                                 Vice President and Secretary


                                           BANK:

                                           WELLS FARGO BANK TEXAS,
                                           NATIONAL ASSOCIATION


                                           By:   /s/ SCOTT GILDEA
                                                 ------------------------------
                                                 Scott Gildea
                                                 Assistant Vice President


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<PAGE>


The Parent hereby consents and agrees to this Fifth Amendment and agrees that
the OilQuip Guaranty shall remain in full force and effect, shall continue to
the be legal, valid, and binding obligations of the Parent, and shall continue
to guarantee the indebtedness and obligations described in the OilQuip Guaranty
as such guaranteed obligations are amended by this Fifth Amendment including,
without limitation, such OilQuip Guaranty shall be enforceable against OilQuip
in accordance with its terms.

                                              GUARANTOR:

                                              OilQuip Rentals, Inc.,
                                              a Delaware corporation


                                              By:  /s/ THEODORE F. POUND, III
                                                   -----------------------------
                                                   Theodore F. Pound, III
                                                   Vice President and Secretary


Munawar and Jayne Hidayatallah hereby jointly and severally consent and agree to
this Fifth Amendment and agree that the Hidayatallah Guaranty shall remain in
full force and effect, shall continue to the be legal, valid, and binding
obligations of Munawar and Jayne Hidayatallah, and shall continue to guaranty
the indebtedness and obligations described in the Hidayatallah Guaranty as such
guaranteed obligations are amended by this Fifth Amendment including, without
limitation, such Hidayatallah Guaranty shall be enforceable against Munawar and
Jayne Hidayatallah in accordance with its terms.

                                              GUARANTOR:



                                              /S/ MUNAWAR HIDAYATALLAH
                                              ---------------------------------
                                              Munawar Hidayatallah



                                              /S/ JAYNE HIDAYATALLAH
                                              ---------------------------------
                                              Jayne Hidayatallah

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<PAGE>

Allis-Chalmers consents and agrees to this Fifth Amendment and agrees to comply
with and be bound by all of the terms hereof, and further agrees that its
guaranty shall remain in full force and effect, shall continue to the be legal,
valid, and binding obligations of Allis-Chalmers, and shall continue to
guarantee the indebtedness and obligations described in its guaranty as such
guaranteed obligations are amended by this Fifth Amendment including, without
limitation, such guaranty shall be enforceable against Allis-Chalmers in
accordance with its terms.

                                               GUARANTOR:

                                               Allis-Chalmers Company,
                                               a Delaware corporation


                                               By:  /s/ MUNAWAR HIDAYATALLAH
                                                    ---------------------------
                                                    Munawar Hidayatallah
                                                    Chief Executive Officer



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