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                                                                   EXHIBIT 10.32

                       FIRST AMENDMENT TO CREDIT AGREEMENT

         THIS FIRST AMENDMENT TO CREDIT AGREEMENT (as same may be renewed,
extended, modified, restated amended and/or rearranged, the "FIRST AMENDMENT")
dated effective as of February 1, 2002, is between MOUNTAIN COMPRESSED AIR,
INC., a Texas corporation (hereinafter referred to as "BORROWER") and WELLS
FARGO ENERGY CAPITAL, INC. ("LENDER").

                                    RECITALS:

         A. Lender and Borrower entered into that certain Credit Agreement dated
as of February 6, 2001, as same may be amended or restated from time to time
(the "AGREEMENT) in conjunction with additional senior secured credit facility
from Wells Fargo Bank Texas, National Association ("WFB"), dated February 6,
2001 (the "SENIOR CREDIT FACILITY");.

         B. Allis-Chalmers Corporation, a Delaware corporation
("ALLIS-CHALMERS") has acquired all of the outstanding stock of Borrower's
parent, OilQuip Rental Tools, Inc. (the "PARENT"). In connection with the
merger, Borrower obtained an increase in funds available under the Senior Credit
Facility.

         C. Pursuant to Borrower's and Allis-Chalmers' request that Lender (i)
consent to the merger of Parent into Allis-Chalmers, (ii) consent to an increase
in the Line of Credit Note under the Senior Credit Facility by $700,000 to
$1,200,000, and (iii) exchange that certain Warrant to purchase 1,350,000 Shares
of the Common Stock of Borrower, dated February 6, 2001, held by Lender with a
Warrant to purchase 465,000 Shares of the Common Stock of Allis-Chalmers, in
favor of Lender (collectively, the "LOAN MODIFICATIONS"), as more particularly
agreed to into that certain Warrant Purchase Agreement dated effective as of
February 1, 2002, between Allis-Chalmers and Lender.

         D. Lender and Borrower entered into that certain Letter Agreement dated
August 23, 2001, wherein Lender agreed to waive compliance with SECTION 5.04 and
SECTION 5.09 of the Agreement and consented to the Loan Modifications and pledge
of additional collateral (the "FIRST AMENDMENT COLLATERAL") to WFB, provided
Borrower execute and deliver in conjunction therewith any and all security
agreements, financing statements, and/or other documentation requested by, and
satisfactory to, Lender to effect a pledge of the First Amendment Collateral on
a second lien basis to Lender.

         E. Allis-Chalmers executed that certain General Pledge Agreement (the
"ALLIS-CHALMERS PLEDGE") pledging, among other things, 100 shares of stock
(being one hundred percent (100%) of the stock of all kinds and classes) of
Parent, securing all present and future Indebtedness by Borrower to Lender,
including, without limitation, payment of the $2,000,000.00 Term Note referred
to in the Agreement (the "NOTE").

<PAGE>

         F. Borrower has requested that Lender, among other things, permit
Borrower to sell Houston Dynamic Service, Inc., a Texas corporation ("HOUSTON
DYNAMIC"). Lender has agreed to do so, subject to the terms and conditions
contained herein.

         G. Borrower and Lender now desire to enter into this First 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 First
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 First Amendment. It is hereby confirmed
that the term "AGREEMENT" includes the Agreement as amended by this First
Amendment.

                                    ARTICLE 2

                                   AMENDMENTS

         Section 2.1 AMENDMENT TO SECTION 1.2(c). Effective as of the date
hereof, Section 1.2(c) of the Agreement is hereby amended to read in its
entirety as follows:

                  "(c) WARRANT. Allis-Chalmers Corporation, a Delaware
                  corporation ("ALLIS CHALMERS"), shall sell and issue to Lender
                  a warrant to purchase 465,000 shares of stock of
                  Allis-Chalmers in the form of Warrant A to that certain
                  Warrant Purchase Agreement (the "WARRANT PURCHASE AGREEMENT")
                  dated effective as of February 1, 2002, between Allis-Chalmers
                  and Lender, attached hereto as EXHIBIT B."

         Section 2.2 Addition of Section 2.15. Effective as of the date hereof,
Section 2.15 is hereby added as follows:

                  "Section 2.15. ALLIS-CHALMERS AND SUBSIDIARIES. Allis-Chalmers
         is a Delaware corporation that owns one hundred percent (100%) of the
         stock of all kinds and classes of Parent which is a Delaware
         corporation that owns one hundred percent (100%) of the stock of all
         kinds and classes of Borrower, which is a Texas corporation that owns
         one hundred percent (100%) of the stock of all kinds and classes of
         Houston Dynamic, which stock is being sold to Clayton Lau pursuant to
         the terms and conditions set forth in that certain Stock Purchase
         Agreement dated as of November 30, 2001, between Borrower and Clayton
         Lau."

                                      -2-
<PAGE>

         Section 2.3 ADDITION OF SECTION 2.16. Effective as of the date hereof,
Section 2.16 is hereby added as follows:

                  "Allis-Chalmers and OilQuip are in compliance in all material
         respects with all applicable provisions of ERISA; neither
         Allis-Chalmers nor OilQuip has violated any provision of any defined
         employee pension benefit plan (as defined in ERISA) maintained or
         contributed to by any of said parties (each, a "PLAN") no Reportable
         Event as defined in ERISA has occurred and is continuing with respect
         to any Plan initiated by any of said parties; all of said parties have
         met their minimum funding requirements under ERISA with respect to each
         Plan, and each Plan will be able to fulfill its benefit obligations as
         they come due in accordance with the Plan documents and generally
         accepted accounting principles. All previous problems and matters with
         the Pension Benefit Guaranty Corporation by any of said parties have
         been fully resolved and disclosed to Lender."

         Section 2.4 AMENDMENT TO SECTION 4.03. Effective as of the date hereof,
Section 4.03 is hereby amended to read in its entirety as follows:

                  "4.03 FINANCIAL STATEMENTS. Allis-Chalmers will promptly
         furnish to Lender from time to time upon request such information
         regarding the business and affairs and financial condition of
         Allis-Chalmers and its Subsidiaries (as used herein, "SUBSIDIARY" shall
         mean any corporation of which more than 50% of the issued and
         outstanding securities having ordinary voting power for the election of
         directors is owned or controlled, directly or indirectly, by
         Allis-Chalmers and/or one or more of its subsidiaries) as Lender may
         reasonably request, and will furnish to Lender:

                           (a) Annual Reports - promptly after becoming
         available and in any event within 90 days after the close of each
         fiscal year of Allis-Chalmers, the audited consolidated and
         consolidating balance sheets of Allis-Chalmers and its Subsidiaries as
         at the end of such year, the audited consolidated and consolidating
         statements of profit and loss of Allis-Chalmers and its Subsidiaries
         for such year and the audited consolidated and consolidating statements
         of reconciliation of capital accounts of the Borrower and its
         Subsidiaries for such year, setting forth in each case for fiscal years
         ending after December 31, 2000, in comparative form the corresponding
         figures for the preceding fiscal year, accompanied by the related
         report of independent public accountants acceptable to Lender which
         report shall be to the effect that such statements have been prepared
         in accordance with generally accepted accounting principles
         consistently followed throughout the period indicated except for such
         changes in such principles with which the independent public
         accountants shall have concurred; and

                           (b) Quarterly Reports - promptly after becoming
         available and in any event within 45 days after the end of each of the
         first three quarterly periods in each fiscal year of Allis-Chalmers,
         the consolidated and consolidating balance sheets of Allis-Chalmers and
         its Subsidiaries as at the end of such period, the consolidated and
         consolidating statements of profit and loss of Allis-Chalmers and its


                                      -3-
<PAGE>

         Subsidiaries for such quarter and for the period from the beginning of
         the fiscal year to the close of such quarter, and the consolidated and
         consolidating statement of reconciliation of capital accounts of
         Allis-Chalmers and its Subsidiaries for such quarter and for the period
         from the beginning of the fiscal year to the close of such quarter,
         setting forth in each case for fiscal years ending after December 31,
         2000, in comparative form the corresponding figures for the
         corresponding period of the preceding fiscal year, certified by the
         principal financial officer of Allis-Chalmers to have been prepared in
         accordance with generally accepted accounting principles consistently
         followed throughout the period indicated except to the extent stated
         therein, subject to normal changes resulting from year-end adjustment;

                           (c) Audit Reports - promptly upon receipt thereof,
         one copy of each other report submitted to Allis-Chalmers or any
         Subsidiary by independent accountants in connection with any annual,
         interim or special audit made by them of the books of Allis-Chalmers or
         any Subsidiary;

                           (d) contemporaneously with each annual and quarterly
         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;

                           (e) SEC and Other Reports - promptly upon their
         becoming available, one copy of each financial statement, report,
         notice or proxy statement sent by Allis-Chalmers to stockholders
         generally, and of each regular or periodic report and any registration
         statement, prospectus or written communication (other than transmittal
         letters) in respect thereof filed by Borrower with or received by
         Borrower in connection therewith from, any securities exchange or the
         Securities and Exchange Commission or any successor agency; and

                           (f) From time to time such other information as
         Lender may reasonably request.

         Section 2.5 AMENDMENT TO SECTION 4.09. Effective as of the date hereof,
Section 4.09 of the Agreement is hereby amended to read in its entirety as
follows:

                  "4.09 FINANCIAL CONDITION. Maintain, or cause to be
         maintained, Borrower's financial condition as follows using generally
         accepted accounting principles consistently applied and used
         consistently with prior practices (except to the extent modified by the
         definitions herein):

                  (a) Beginning September 30, 2001, Tangible Net Worth not at
         any time less than eighty-five percent (85%) of Tangible Net Worth as
         of June 30, 2001 (plus seventy-five percent (75%) of cumulative net
         income after June 30, 2001, excluding any fiscal quarters in which net
         income is negative), plus one hundred percent (100%) of equity
         offerings after the date hereof, with "TANGIBLE NET WORTH" defined
         herein as the aggregate of total stockholders' equity plus the Seller
         Note less any intangible assets.

                                      -4-
<PAGE>

                  (b) Borrower shall maintain a Fixed Charge Coverage Ratio not
         less than 1.1 to 1.0 for the twelve (12) month period ending on the
         last day of each fiscal quarter, beginning with the fiscal quarter
         ending March 31, 2001, with "EBITDA" defined herein as net income plus
         interest charges, plus taxes, plus depreciation, amortization and
         non-cash charges on a trailing twelve (12) month basis and with "FIXED
         CHARGE COVERAGE Ratio" defined herein as (i) EBITDA plus applicable
         operating lease payments less unfinanced capital expenditures divided
         by (ii) the aggregate of total interest charges (excluding any
         applicable paid-in-kind ("PIK") charges), scheduled principal payments,
         operating lease payments, cash dividends paid, and paid taxes for the
         same period. EBITDA will be computed on a trailing twelve (12) months
         basis. Through September 30, 2001, fixed charges will be annualized.
         Thereafter, fixed charges will be on a trailing twelve (12) month
         basis.

                  (c) Beginning December 31, 2002, Borrower shall maintain a
         Total Funded Debt to EBITDA Ratio not more than 2.50 to 1.0; and 2.0 to
         1.0 for each quarter thereafter, with "TOTAL FUNDED DEBT TO EBITDA
         RATIO" defined as Total Funded Debt divided by the twelve (12) trailing
         months EBITDA. "TOTAL FUNDED DEBT" is defined herein as all
         interest-bearing obligations of Borrower, whether secured or unsecured,
         senior or subordinated, (excluding the Seller Note).

                  (d) Notwithstanding anything to the contrary contained in this
         Section 4.09, Lender hereby waives Borrower's Default in this Section
         4.09 for the time period ending September 30, 2001 and Lender agrees to
         forebear exercising any remedy due to said Defaults. This is a limited,
         one-time waiver only and only applies to the above Defaults ending the
         period September 30, 2001 and shall not affect Lender's right to
         enforce strict compliance with all other terms and conditions of the
         Loan Documents including, without limitation, compliance with this
         Section 4.09 for all time periods other than the period ending
         September 30, 2001.

         Section 2.6 AMENDMENT TO SECTION 5.05. Effective as of the date hereof,
Section 5.05 of the Agreement is hereby amended to read in its entirety as
follows:

                  "5.05 MERGER, CONSOLIDATION, TRANSFER OF ASSETS. Merge into or
         consolidate with any other entity; make any substantial change in the
         nature of Borrower's business as conducted as of the date hereof;
         acquire all or substantially all of the assets of any other entity; nor
         sell, lease, transfer or otherwise dispose of all or a substantial or
         material portion of Borrower's assets except in the ordinary course of
         business; PROVIDED HOWEVER, Borrower may sell to Clayton Lau the stock
         of Houston Dynamic pursuant to the terms and conditions set forth in
         that certain Stock Purchase Agreement dated as of November 30, 2001,
         between Borrower and Clayton Lau."

         Section 2.7 Effective as of the date hereof, Section 6.01(j) of this
Agreement is hereby amended to read in its entirety as follows:

                                      -5-
<PAGE>

                  "(j) Any "EVENT OF DEFAULT" as defined under the WF Bank Loan
         Documents, the WF Finance Loan Documents, the Loan Agreement dated
         February 1, 2002, between Allis-Chalmers and Lender, or the Seller
         Note, the Lau-Houston Dynamic Note or any amendments, modifications or
         restatements thereof."

         Section 2.8 EXHIBIT B. Effective as of the date hereof, Exhibit B to
         the Agreement is hereby deleted in its entirety and Exhibit B attached
         hereto is substituted in lieu thereof.

                                    ARTICLE 3

                         REPRESENTATIONS AND WARRANTIES

         In order to induce Lender to enter into this First Amendment and to
continue to make the loans provided for in the Agreement, 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 Borrower contained in the
Agreement and the Loan Documents and otherwise made in writing by or on behalf
of 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 First Amendment, except for such changes in the
facts represented and warranted or amended by this First Amendment as are not in
violation of the Agreement and the Loan Documents.

         Section 3.2 COMPLIANCE WITH OBLIGATIONS. 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 Borrower prior to or
at the time of delivery of this First Amendment.

         Section 3.3 DEFAULTS. There exists, and after giving effect to this
First 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 Borrower is a party.

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

                                    ARTICLE 4

                                   CONDITIONS

         Lender has relied upon the representations and warranties contained in
this First 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 Borrower made or referred to herein, to the
performance by Borrower of its obligations to be performed under the Agreement
and the Loan Documents on or before the date of this First Amendment and to the
following further conditions:

                                      -6-
<PAGE>

         Section 4.1 THE NOTE. Houston Dynamic and Clayton Lau shall have duly
and validly issued, executed and delivered to Borrower that certain promissory
note in the principal amount of Nine Hundred Thirty Thousand Dollars
($930,000.00) (as same may be renewed, extended or modified and all promissory
notes executed in renewal, extension, modification or substitution therefore,
"LAU-HOUSTON DYNAMIC NOTE") and Borrower shall endorse and deliver to WFB the
Lau-Houston Dynamic Note pursuant to the terms and provisions of that certain
Collateral Assignment of Note and Liens of even date herewith by and between
Borrower and Lender, and such other documentation requested by, and satisfactory
to, Lender to effectuate a pledge of the Lau-Houston Dynamic Note on a second
lien basis to Lender.

         Section 4.2 COLLATERAL ASSIGNMENT OF NOTE AND LIENS. Borrower shall
have duly and validly executed and delivered to Lender a Collateral Assignment
of Note and Liens in form and substance satisfactory to Lender.

         Section 4.3 WARRANT. Borrower shall sell and issue to Lender a warrant
to purchase 465,000 shares of the common stock of Allis-Chalmers at $0.15 per
share ("WARRANT A") as more particularly set forth in that certain Warrant
Purchase Agreement and Shareholder's Agreement of even date herewith between
Borrower and Lender, attached hereto as EXHIBIT B.

         Section 4.4 SECURITY AGREEMENT. Borrower shall have duly and validly
issued, executed, and delivered to Lender a Security Agreement and related
financing statements and other documents required to be executed by Lender in
form and substance satisfactory to Lender.

         Section 4.5 GENERAL PLEDGE AGREEMENT. Allis-Chalmers shall have duly
and validly issued, executed, and delivered to Lender a General Pledge Agreement
and related financing statements and other documents required to be executed by
Lender in form and substance satisfactory to Lender.

         Section 4.6 OFFICER'S CERTIFICATE. Lender shall have received a
certificate of the officers of Borrower setting forth (i) resolutions of its
boards of directors in form and substance satisfactory to Lender authorizing
Borrower (and such other parties as may be required by Lender) to execute the
Loan Documents to which it is party, and (ii) specimen signatures of the
officers so authorized.

         Section 4.7 ADDITIONAL DOCUMENTATION. Borrower shall deliver to Lender
such additional approvals, opinions or documents as Lender may reasonably
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 First Amendment (including,
without limitation, the Note), whether or not such Loan Documents shall be
expressly amended or supplemented in connection with this First Amendment.

                                      -7-
<PAGE>

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

         Section 5.3 EFFECTIVE DATE. Except as otherwise expressly provided
herein, the effective date of all provisions of this First 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 First
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 First 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 ENTIRE AGREEMENT. THIS FIRST AMENDMENT AND ALL OTHER
INSTRUMENTS, DOCUMENTS, AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH
THIS FIRST 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 FIRST AMENDMENT AND THE OTHER INSTRUMENTS,
DOCUMENTS AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS FIRST
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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                          SIGNATURE PAGES TO FOLLOW.]





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         IN WITNESS WHEREOF, the parties hereto have caused this instrument to
be duly executed as of the 1st day of February, 2002.


                                        LENDER:

                                        WELLS FARGO ENERGY CAPITAL, INC.,


                                        By:   /S/ GARY MILAVEC
                                              --------------------------
                                              Gary Milavec
                                              Senior Vice President


                                      S-1


<PAGE>




                                      BORROWER:

                                      MOUNTAIN COMPRESSED AIR, INC.


                                      By:   /S/ MUNAWAR H. HIDAYATALLAH
                                            ------------------------------------
                                            Munawar H. Hidayatallah
                                            Chairman and Chief Executive Officer


OilQuip Rentals, Inc. hereby consents and agrees to this First Amendment and
agrees to comply with and be bound by all the terms hereof.

                                      OilQuip Rentals, Inc.,
                                      a Delaware corporation


                                      By:   /S/ MUNAWAR H. HIDAYATALLAH
                                            ------------------------------------
                                            Munawar H. Hidayatallah
                                           Chairman and Chief Executive Officer


Allis-Chalmers hereby consents and agrees to this First Amendment and agrees to
comply with and be bound by all the terms hereof.


                                      GUARANTOR:
                                      Allis-Chalmers Company,
                                      a Delaware corporation


                                      By:   /S/ MUNAWAR H. HIDAYATALLAH
                                            ------------------------------------
                                            Munawar H. Hidayatallah
                                           Chairman and Chief Executive Officer

                                      S-2