SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                 SCHEDULE 13D/A

                    Under the Securities Exchange Act of 1934
                               (Amendment No. 1)*

                           Allis-Chalmers Corporation
                                (NAME OF ISSUER)

                     Common Stock, par value $0.15 per share
                         (TITLE OF CLASS OF SECURITIES)

                                    019645407
                                 (CUSIP NUMBER)

                             Brad L. Whitlock, Esq.
                              Jackson Walker L.L.P.
                                 901 Main Street
                                   Suite 6000
                               Dallas, Texas 75202
                  (NAME, ADDRESS AND TELEPHONE NUMBER OF PERSON
                AUTHORIZED TO RECEIVE NOTICES AND COMMUNICATIONS)

                                February 19, 2003
                      (DATE OF EVENT WHICH REQUIRES FILING
                               OF THIS STATEMENT)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition which is the subject of this Schedule 13D, and is filing this
schedule because of ss.ss. 240. 13d-1(e), 240.13d-1(f) or 240.13d-1(g), check
the following box [ ].

NOTE: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 240.13d-7 for other
parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).


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1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Energy Spectrum Partners, LP
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     OO
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Delaware
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     PN
--------------------------------------------------------------------------------

                                                                          Page 2

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1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Energy Spectrum Capital LP
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Delaware
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     PN
--------------------------------------------------------------------------------

                                                                          Page 3

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1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Energy Spectrum LLC
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     OO
--------------------------------------------------------------------------------

                                                                          Page 4

--------------------------------------------------------------------------------
1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Sidney L. Tassin
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     IN
--------------------------------------------------------------------------------

                                                                          Page 5

--------------------------------------------------------------------------------
1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     James W. Spann
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     IN
--------------------------------------------------------------------------------

                                                                          Page 6


--------------------------------------------------------------------------------
1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     James P. Benson
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     IN
--------------------------------------------------------------------------------

                                                                          Page 7


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1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Leland B. White
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     IN
--------------------------------------------------------------------------------

                                                                          Page 8


--------------------------------------------------------------------------------
1.   Name of Reporting Persons.
     I.R.S. Identification Nos. of above persons (entities only).

     Thomas O. Whitener, Jr.
--------------------------------------------------------------------------------
2.   Check the Appropriate Box If a Member of a Group (See Instructions)
     (a)  [_]
     (b)  [X]
--------------------------------------------------------------------------------
3.   SEC Use Only

--------------------------------------------------------------------------------
4.   Source of Funds (See Instructions)
     N/A
--------------------------------------------------------------------------------
5.   Check If Disclosure of Legal Proceedings Is Required Pursuant to
     Items 2(d) or 2(e)                                             [_]

--------------------------------------------------------------------------------
6.   Citizenship or Place of Organization
     Texas
--------------------------------------------------------------------------------
               7.   Sole Voting Power
  NUMBER OF
   SHARES      -----------------------------------------------------------------
BENEFICIALLY   8.   Shared Voting Power
 OWNED BY           14,872,363
    EACH       -----------------------------------------------------------------
  REPORTING    9.   Sole Dispositive Power
   PERSON
    WITH       -----------------------------------------------------------------
               10.  Shared Dispositive Power
                    14,872,363
--------------------------------------------------------------------------------
11.  Aggregate Amount Beneficially Owned by Each Reporting Person
     14,872,363
--------------------------------------------------------------------------------
12.  Check Box If the Aggregate Amount in Row (11) Excludes Certain Shares
     (See Instructions)                                               [_]
--------------------------------------------------------------------------------
13.  Percent of Class Represented by Amount in Row (11)
     53.22%
--------------------------------------------------------------------------------
14.  Type of Reporting Person (See Instructions)
     IN
--------------------------------------------------------------------------------

                                                                          Page 9




SCHEDULE 13D - AMENDMENT NO. 1

         The undersigned hereby amend the Schedule 13D filing made on February
20, 2002 (the "Schedule 13D") pursuant to Rule 13d-2(a) of Regulation 13D-G of
the General Rules and Regulations under the Securities Exchange Act of 1934, as
amended, as set forth below (terms defined in the Schedule 13D are used with the
same meaning except as otherwise defined herein):

ITEM 1.  SECURITY AND ISSUER SECURITIES ACQUIRED.

         Item 1 is hereby amended and restated to read in its entirety as
follows:

         Security: Common Stock of Allis-Chalmers Corporation ("Common Stock").

         Issuer: Allis-Chalmers Corporation ("Issuer"), 7660 Woodway, Suite 200,
Houston, Texas 77063.

ITEM 2. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

         Item 3 is hereby amended and restated to read in its entirety as
follows:

         ES Partners acquired all of its Common Stock in exchange for all of the
capital stock of Strata Directional Technology, Inc. ("Strata"), a Texas
corporation, owned by ES Partners. The repricing of the Preferred Stock (as
defined below) and the issuance of a warrant to purchase 875,000 shares of
Common Stock were contemplated by the terms of the initial transaction. See Item
4 below.

ITEM 3.  PURPOSE OF TRANSACTION.

         Item 4 is hereby amended and restated to read in its entirety as
follows:

         Pursuant to a Stock Purchase Agreement dated effective February 1,
2002, which transaction was closed on February 7, 2002, ES Partners sold all of
its capital stock in Strata to the Issuer in exchange for 6,559,863 shares of
Common Stock, a presently exercisable warrant to purchase 437,500 shares of
Common Stock at an exercise price of $.15 per share and 3,500,000 shares of
Issuer's Series A 10% Cumulative Convertible Preferred Stock ("Preferred
Stock"). Pursuant to the terms of the Preferred Stock, the conversion price was
required to be fixed at $.19 per share, however by agreement of ES Partners and
the Issuer, as of February 19, 2003, the conversion price was set at $.50 per
share, thus the preferred shares are presently convertible into 7,000,000 shares
of Common Stock. Since all of the outstanding shares of Preferred Stock, except
one, were not redeemed by the Issuer prior to the first anniversary of the
closing, on February 19, 2003 the Issuer issued ES Partners an additional
immediately exercisable warrant to purchase 875,000 shares of Common Stock at an
exercise price of $.15 per share.

         Pursuant to the terms of the Preferred Stock, ES Partners has the right
to elect three (3) members of Issuer's board of directors. ES Partners has
designated Messrs. Whitener, Spann and Michael D. Tapp to serve on the Issuer's
board of directors. ES Partners, as the holder of the Preferred Stock, also has
the right to elect additional directors in the event its shares are not redeemed
as required by the terms of the Preferred Stock, and to approve specified major
decisions made by the Issuer. On February 19, 2003 by agreement of the parties,
the conversion price of the Preferred Stock was fixed at $.50 per share. All
except one share of the Preferred Stock must be redeemed by the Issuer upon the
occurrence of certain events as required by the terms of the Preferred Stock.

         Each of the Reporting Persons acquired shares of Common Stock as an
investment.

         The Reporting Persons reserve the right to (i) dispose of all or part
of their investment in the Stock at any time, (ii) acquire additional equity
securities of the Issuer or its affiliates, in the open market, in private
transactions or otherwise, (iii) propose a merger or other business combination
with the Issuer or its affiliates, or (iv) to take any other action with respect
to the Issuer. Any such purchases will depend upon the market prices for the
shares of Common Stock, the number of shares which may become available for
purchase at prices which each of the Reporting Persons regard as attractive and
various other factors which each of the Reporting Persons may determine to be
relevant.

                                                                         Page 10


         Except as set forth in this Item 4, the Reporting Persons have no
present plans or proposals that relate to or that would result in any of the
actions or events described in paragraphs (a) through (j) of Item 4 of Schedule
13D. However, the Reporting Persons retain their respective rights to modify
their plans with respect to the transactions described in this Item 4, to
acquire or dispose of securities of the Issuer and to formulate plans and
proposals which could result in the occurrence of any such events, subject to
applicable laws and regulations.

ITEM 4.  INTEREST IN SECURITIES OF THE ISSUER.

         Item 5 is hereby amended and restated to read in its entirety as
follows:

         Pursuant to Rule 13d-3(a), at the close of business on February 19,
2003, each of ES Partners, ES Capital and ES LLC may be deemed to be the
beneficial owner of 14,872,363 shares of the Common Stock, which constitutes
approximately 53% of the shares of the Common Stock outstanding on February 19,
2003, according to information provided by the Issuer (the "Outstanding
Shares"). Each of the Reporting Persons, either directly or indirectly, has or
shares the power to vote or to direct the vote and to dispose or to direct the
disposition of, such shares of Stock.

         The Reporting Persons have not purchased shares of Stock in open market
transactions.

         (d)      Not applicable

         (e) Not applicable.

ITEM 5.  MATERIAL TO BE FILED AS EXHIBITS.

         Exhibit 7.1 Stock Purchase Agreement*
         Exhibit 7.2 Certificate of Designation, Preferences and Rights of the
           Series A 10% Cumulative Convertible Preferred Stock of Allis-Chalmers
           Corporation*
         Exhibit 7.3 Warrant*
         Exhibit 7.4 Registration Rights Agreement By and Among Allis-Chalmers
           Corporation and Energy Spectrum Partners, LP*
         Exhibit 7.5 Shareholders' Agreement Among Allis-Chalmers Corporation
           and the Shareholders and Warrantholder who are Signatories hereto*
         Exhibit 7.6 Warrant (incorporated by reference to the Issuer's Form 8-K
           dated February 19, 2003)
         Exhibit 7.8 Side Letter Agreement regarding Preferred (incorporated by
           reference to the Issuer's Form 8-K dated February 19, 2003)


         *  Previously filed


                                                                         Page 11



SIGNATURES

         After reasonable inquiry and to the best of the knowledge and belief of
the undersigned, the undersigned certify that the information set forth in this
statement is true, complete and correct.

         Pursuant to Rule 13d-1(k)(l)(iii) of Regulation 13D-G of the General
Rules and Regulations of the Securities and Exchange Commission under the
Securities Exchange Act of 1934, as amended, the undersigned agree that the
attached statement is filed on behalf of each of them in the capacities set
forth below.

DATED: February 19, 2003

                                 ENERGY SPECTRUM PARTNERS, LP

                                 By: Energy Spectrum Capital LP, General Partner
                                 By: Energy Spectrum LLC, General Partner


                                     By:  /s/ Thomas O. Whitener, Jr.
                                          --------------------------------------
                                     Its: Chief Operating Officer


                                 ENERGY SPECTRUM CAPITAL LP

                                     By: Energy Spectrum LLC, General Partner


                                         By: /s/ Thomas O. Whitener, Jr
                                             -----------------------------------
                                         Its: Chief Operating Officer


                                 ENERGY SPECTRUM LLC


                                 By:  /s/ Thomas O. Whitener, Jr
                                      -----------------------------------
                                 Its: Chief Operating Officer


                                 /s/ Sidney L. Tassin
                                 ----------------------------------------
                                 Sidney L. Tassin


                                 /s/ James W. Spann
                                 ----------------------------------------
                                 James W. Spann


                                 /s/ James P. Benson
                                 ----------------------------------------
                                 James P. Benson


                                 /s/ Leland B. White
                                 ----------------------------------------
                                 Leland B. White


                                 /s/ Thomas O. Whitener, Jr.
                                 ----------------------------------------
                                 Thomas O. Whitener, Jr.


                                                                         Page 12