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                                                                   EXHIBIT 10.33

                      SECOND AMENDMENT TO CREDIT AGREEMENT

         THIS SECOND AMENDMENT TO CREDIT AGREEMENT (this "AMENDMENT") dated
effective as of February 1, 2003, 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 amended by that certain First Amendment to Credit
Agreement dated February 1, 2002 (as amended, the "AGREEMENT) in conjunction
with that certain senior secured credit facility from Wells Fargo Bank Texas,
National Association ("WFB"), dated February 6, 2001, as same has been amended
from time to time (the "SENIOR CREDIT FACILITY") and Master Lease and Supplement
No. 69749-1000 (the "EQUIPMENT LEASE") between Borrower and Wells Fargo
Equipment Finance, Inc. ("WFB FINANCE").

         B. Borrower and WFB have agreed to enter into that certain Sixth
Amendment to Credit Agreement (the "SIXTH AMENDMENT TO SENIOR CREDIT Facility")
and Borrower and WFB Finance have entered into that certain Forbearance
Agreement dated January 17, 2003 (the "WFB FINANCE FORBEARANCE AGREEMENT").

         C. Certain Events of Default under the Agreement have occurred
including: (i) Borrower's failure to comply with the financial covenants set
forth under Section 4.09 of the Agreement, (ii) Borrower's failure to pay
accrued interest since July 3, 2002, and (iii) Borrower's default under the
Senior Credit Facility as more particularly described under the Sixth Amendment
to Senior Credit Facility and under the Equipment Lease as more particularly
described under the WFB Finance Forbearance Agreement (the "DESIGNATED
DEFAULTS").

         D. The amount of past due interest under the Term Loan through December
31, 2002, is $122,666.67 ("PAST DUE INTEREST AMOUNT").

         E. Borrower has requested that Lender, among other things, forebear
exercising any remedies with respect to the Designated Defaults, receipt of
payment of the Past Due Interest Amount until June 30, 2003, and agree to
rearrange current interest payments under the Term Loan. Lender has agreed to do
so, subject to the terms and conditions contained herein.

         F. Borrower and Lender now desire to enter into this 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:

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                                    ARTICLE 1

                                  GENERAL TERMS

         Section 1.1 TERMS DEFINED IN AGREEMENT. As used in this 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 Amendment. It is hereby confirmed that
the term "AGREEMENT" includes the Agreement as amended by this Amendment.

                                    ARTICLE 2

                           AMENDMENTS AND FORBEARANCE

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

                  "(b) REPAYMENT. Principal and interest on the Term Loan shall
                  be repaid in accordance with the provisions of the Term Note
                  with a final maturity date of June 30, 2003 (the "MATURITY
                  DATE"), PROVIDED THAT, the Past Due Interest Amount (as
                  hereinafter defined) shall be due and payable on June 30, 2003
                  and, notwithstanding anything contained in the Term Note to
                  the contrary, all interest accruing from January 1, 2003,
                  through June 30, 2003 shall be payable as follows:

                           (i) one half of such accrued interest shall be due
                  and payable on a current basis on the last day of each month
                  as it accrues, provided that the interest accruing for the
                  month of January, 2003 shall be due and payable on or before
                  February 10, 2003, and

                           (ii) the balance shall be due and payable at the
                  Maturity Date.

                  As used herein, the "Past Due Interest Amount means the amount
                  of past due interest due under the Term Loan, which amount is
                  equal to $122,666.67."


         Section 2.2 FORBEARANCE. From the effective date hereof until the
earlier of (i) the Maturity Date or (ii) an Event of Default under this
Amendment or under the Agreement other than the "Designated Defaults" (the
"FORBEARANCE PERIOD"), Lender will forbear from exercising any remedies against
Borrower with respect to the Designated Defaults.

         Section 2.3 NO WAIVER OF RIGHTS. Acceptance by Lender of any payments
or property hereunder or forbearance by Lender pursuant to the terms of this
Amendment shall not be construed to be a waiver of any default or a waiver of
any rights of Lender against Borrower in accordance with the Agreement, or any
other Loan Documents. Borrower acknowledges and agrees that Lender shall retain

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all remedies and rights of default and shall be permitted to exercise and
enforce such rights and remedies upon the termination of the Forbearance Period.
Borrower further agrees that any remedy available to Lender upon termination of
the Forbearance Period shall not be affected by reason of the forbearance
provided for herein and Borrower shall not assert as a defense thereto the
passage of time, course of dealing, estoppel, laches or any statute of
limitations.

         2.4 LIMITED SCOPE OF AGREEMENT. Except as otherwise expressly set forth
herein, all obligations of Borrower under the Agreement shall remain in full
force and effect as written and shall be enforceable in accordance with their
respective terms, subject to applicable bankruptcy, insolvency, fraudulent
conveyance, reorganization, moratorium and similar laws affecting creditors'
rights and remedies generally. Borrower acknowledges and agrees that, except as
specifically set forth in SECTION 2.2, Lender has not made any agreement to
forbear from exercising or enforcing any rights or remedies it may have as a
result of any other failure by Borrower to comply fully with the Agreement or
the terms of this Amendment.

         2.5 COMPLIANCE WITH EXISTING LOAN DOCUMENTS; ADDITIONAL COVENANTS.
Unless expressly modified or amended herein, Borrower shall comply with, and
shall continue to be bound by, each of the terms and provisions contained in the
Agreement. In addition, Borrower shall comply with, and shall be bound by, each
of the terms and provisions contained herein.


                                    ARTICLE 3

                         REPRESENTATIONS AND WARRANTIES

         In order to induce Lender to enter into this Amendment 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 Amendment, except for such changes in the facts
represented and warranted or amended by this Amendment.

         Section 3.2 ACKNOWLEDGMENT OF INDEBTEDNESS. Borrower acknowledges that
it is indebted to Lender under the Term Note, that the amount of unpaid interest
under the Term Note through December 31, 2002, is $122,666.67, and the
Indebtedness is due and owing by Borrower pursuant to the terms of the Agreement
as amended by this Amendment without offset, defense or counterclaim.


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         Section 3.3 COMPLIANCE WITH OBLIGATIONS. Except for the Designated
Defaults, 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 Amendment.

         Section 3.4 DEFAULTS. Except for the Designated Defaults, there exists,
and after giving effect to this 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 3.5 NO AMENDMENTS. Nothing in Article 3 of this 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 Amendment in agreeing to the amendments to the Agreement set forth herein
and the amendments 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 Amendment and to the following further conditions:

         Section 4.1 RESTRUCTURE DOCUMENTS. Borrower shall have entered into the
Sixth Amendment to Senior Credit Facility and the WFB Finance Forbearance
Agreement shall be in full force and effect. Lender, WFB and WFB Finance shall
have entered into an amendment to the Subordination and Intercreditor Agreement
consenting to the revised payment terms under the Term Note as provided under
this Amendment in form acceptable to Lender.

         Section 4.2 OFFICER'S CERTIFICATE. Lender shall have received a
certificate of the officers of Borrower setting forth (i) resolutions of its
board of directors in form and substance satisfactory Lender authorizing
Borrower to execute this Amendment and such other documents to which it is a
party, and (ii) specimen signatures of the officers so authorized.

         Section 4.3 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 Amendment (including, without
limitation, the Term Note), whether or not such Loan Documents shall be
expressly amended or supplemented in connection with this Amendment.

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         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
Amendment.

         Section 5.3 EFFECTIVE DATE. Except as otherwise expressly provided
herein, the effective date of all provisions of this 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 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 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 AMENDMENT AND ALL OTHER INSTRUMENTS,
DOCUMENTS, AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS
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 AMENDMENT AND THE OTHER INSTRUMENTS, DOCUMENTS AND
AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH THIS 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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         IN WITNESS WHEREOF, the parties hereto have caused this instrument to
be duly executed as of the 1st day of February, 2003.


                                              LENDER:

                                              WELLS FARGO ENERGY CAPITAL, INC.,


                                              By:   /S/ CLAYTON R. TAYLOR
                                                    Clayton R. Taylor
                                                    Vice President


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<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 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 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


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