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                                                                     EXHIBIT 4.1

                 AMENDMENT NO. 1 TO FIRST LIEN CREDIT AGREEMENT

          AMENDMENT NO. 1 (this "Amendment"), dated as of May 5, 2006, among
TECUMSEH PRODUCTS COMPANY, a Michigan corporation (the "Borrower"), the Lenders
party hereto, and CITICORP USA, INC., as administrative agent and collateral
agent for the Lenders and the Issuers (in such capacities, the "Administrative
Agent"), amends certain provisions of the FIRST LIEN CREDIT AGREEMENT, dated as
of February 6, 2006 (as further amended hereby and as the same may be further
amended, supplemented or otherwise modified from time to time, the "Credit
Agreement"), among the Borrower, the financial institutions from time to time
party thereto as lenders (the "Lenders"), the financial institutions from time
to time party thereto as issuing banks (the "Issuers") and the Administrative
Agent.

                                   WITNESSETH:

          WHEREAS, the Borrower's Brazilian Subsidiaries have entered into or
may in the future enter into receivables financing transactions whereby the
Brazilian Subsidiaries discount or sell, either with or without recourse under
Brazilian law, export receivables pursuant to and in accordance with one or more
programs administered by the Brazilian Central Bank (the "Brazilian Receivables
Transactions");

          WHEREAS, as the Brazilian Receivables Transactions may constitute an
Off-Balance Sheet Liability, which constitutes Indebtedness, the incurrence of
which may be prohibited by Section 8.1 of the Credit Agreement; and

          WHEREAS, the Borrower has requested, and the Lenders and the
Administrative Agent have agreed (i) to amend Section 8.1 of the Credit
Agreement to permit the Brazilian Subsidiaries to enter into the Brazilian
Receivables Transactions and (ii) to waive any Default or Event of Default that
may have arisen in connection with such transaction;

          NOW, THEREFORE, in consideration of the premises and the mutual
covenants and provisions hereinafter contained, the parties hereto hereby agree
as follows:

          1. DEFINED TERMS. Capitalized terms used herein and not defined herein
but defined in the Credit Agreement are used herein as defined in the Credit
Agreement.

          2. AMENDMENT TO THE CREDIT AGREEMENT. As of the First Amendment
Effective Date (as defined in Section 4), the Credit Agreement is hereby amended
as follows:

          (a) Section 1.1 of the Credit Agreement is hereby amended by adding
the following defined term in alphabetical order:

               "Brazilian Receivables Transactions" means a transaction whereby
the Brazilian Subsidiaries discount or sell, either with or without recourse
under Brazilian law, export receivables pursuant to and in accordance with one
or more programs administered by the Brazilian Central Bank.

          (b) Clause (k) of Section 8.1 of the Credit Agreement is hereby
amended in its entirety as follows:

               (k) Indebtedness (not otherwise permitted under this Section 8.1)
     incurred (i) in connection with the Brazilian Receivables Transactions;
     provided, however, that the Dollar Equivalent of the aggregate outstanding
     principal amount (or equivalent repurchase obligation) of


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     all such Indebtedness incurred pursuant to this clause (i) shall not exceed
     $150,000,000 at any time and (ii) by any Material Foreign Subsidiary (other
     than in connection with the Brazilian Receivables Transactions mentioned in
     clause (i) above); provided, however, that the Dollar Equivalent of the
     aggregate outstanding principal amount of all such Indebtedness incurred
     pursuant to this clause (ii) shall not exceed $25,000,000 at any time; and

          3. WAIVER. The Lenders party hereto, constituting the Requisite
Lenders, hereby waive any Default or Event of Default that may have arisen as a
result of the Brazilian Receivables Transactions.

          4. CONDITIONS PRECEDENT TO THE EFFECTIVENESS OF THIS AMENDMENT. This
Amendment shall become effective, as of February 6, 2006, on the date (the
"First Amendment Effective Date") when the Administrative Agent shall have
received all of the following, each of which shall be in form and substance
satisfactory to the Administrative Agent:

               (a) this Amendment, executed by the Borrower, the Administrative
Agent and the Requisite Lenders;

               (b) the Consent of Guarantors (attached hereto), executed by each
Guarantor; and

               (c) such additional documentation as the Administrative Agent or
the Requisite Lenders may reasonably require.

          5. REPRESENTATIONS AND WARRANTIES. On and as of the date hereof, and
as of the First Amendment Effective Date, after giving effect to this Amendment,
the Borrower hereby represents and warrants to the Lenders as follows:

               (a) Each of the representations and warranties contained in
Article IV of the Credit Agreement, the other Loan Documents or in any
certificate, document or financial or other statement furnished at any time
under or in connection therewith are true and correct in all material respects
on and as of the date as if made on and as of such date, except to the extent
that such representations and warranties specifically relate to a specific date,
in which case such representations and warranties shall be true and correct in
all material respects as of such specific date; and

               (b) No Default or Event of Default has occurred and is
continuing.

          6. CONTINUING EFFECT; NO OTHER AMENDMENTS. Except as expressly amended
hereby, all of the terms and provisions of the Credit Agreement and the other
Loan Documents are and shall remain in full force and effect. The amendments and
consents contained herein shall not constitute an amendment or a waiver of any
other provision of the Credit Agreement or the other Loan Documents or for any
other purpose except as expressly set forth herein.

          7. LOAN DOCUMENTS. This Amendment is deemed to be a "Loan Document"
for the purposes of the Credit Agreement.

          8. COSTS AND EXPENSES. The Borrower agrees to pay on demand all
reasonable and documented out-of-pocket costs and expenses of the Administrative
Agent in connection with the preparation, execution and delivery of this
Amendment and other instruments and documents to be


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delivered pursuant hereto, including the reasonable and documented fees and
out-of-pocket expenses of counsel for the Administrative Agent with respect
thereto.

          9. GOVERNING LAW; COUNTERPARTS; MISCELLANEOUS.

               (a) This Amendment shall be governed by, and construed and
interpreted in accordance with, the law of the State of New York.

               (b) This Amendment may be executed in any number of counterparts
and by the different parties on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument.

               (c) Section captions used in this Amendment are for convenience
only and shall not affect the construction of this Amendment.

               (d) From and after the First Amendment Effective Date, all
references in the Credit Agreement to the "Agreement" shall be deemed to be
references to such Agreement as modified hereby and this Amendment and the
Credit Agreement shall be read together and construed as a single instrument.

                            [signature pages follow]


                                       3

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          IN WITNESS WHEREOF, the undersigned parties have executed this
Amendment No. 1 to the Credit Agreement to be effective for all purposes as of
the First Amendment Effective Date.

                                        Borrower

                                        TECUMSEH PRODUCTS COMPANY
                                        as Borrower


                                        By: /s/ JAMES S. NICHOLSON
                                            ------------------------------------
                                        Name: James S. Nicholson
                                        Title: Vice President, Treasurer & CFO


                                        Administrative Agent

                                        CITICORP USA, INC.,
                                        as Administrative Agent, Collateral
                                        Agent, Dollar Swing Loan Lender, Issuer
                                        and as a Lender


                                        By: /s/ SEBASTIEN DELASNERI
                                            ------------------------------------
                                        Name: Sebastien Delasneri
                                        Title: Vice President


                                        Lenders

                                        CITICORP USA, INC.,
                                        as Lender


                                        By: /s/ SEBASTIEN DELASNERI
                                            ------------------------------------
                                        Name: Sebastien Delasneri
                                        Title: Vice President


                                        JPMORGAN CHASE BANK, N.A.
                                        as Thai Swing Loan Lender and as a
                                        Lender


                                        By: /s/ JEFFREY W. SWARTZ
                                            ------------------------------------
                                        Name: Jeffrey W. Swartz
                                        Title: Vice President


                                        BANK OF AMERICA, N.A. as Documentation
                                        Agent and Lender


                                        By: /s/ EDWARD M. BARTKOWSKI
                                            ------------------------------------
                                        Name: Edward M. Bartkowski
                                        Title: Senior Vice President

       [SIGNATURE PAGE TO AMENDMENT NO. 1 TO FIRST LIEN CREDIT AGREEMENT]

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                                        LASALLE BANK MIDWEST N.A.
                                        as a Lender


                                        By: /s/ GREG GENTRY
                                            ------------------------------------
                                        Name: Greg Gentry
                                        Title: First Vice President


                                        COMERICA BANK
                                        as a Lender


                                        By: /s/ CATHERINE MEISTER YOUNG
                                            ------------------------------------
                                        Name: Catherine Meister Young
                                        Title: Vice President


                                        WELLS FARGO FOOTHILL, LLC
                                        as a Lender


                                        By: /s/ JUAN BARRERA
                                            ------------------------------------
                                        Name: Juan Barrera
                                        Title: Vice President


                                        ABLECO FINANCE LLC
                                        on behalf of itself and its affiliates
                                        as a Lender


                                        By: /s/ KEVIN GENDA
                                            ------------------------------------
                                        Name: Kevin Genda
                                        Title: Senior Vice President


                                        NORTH FORK BUSINESS CAPITAL CORPORATION
                                        as a Lender


                                        By: /s/ ARI KAPLAN
                                            ------------------------------------
                                        Name: Ari Kaplan
                                        Title: Vice President


                                        GENERAL ELECTRIC CAPITAL CORPORATION
                                        as a Lender


                                        By: /s/ DWAYNE COKER
                                            ------------------------------------
                                        Name: Dwayne Coker
                                        Title: Duly Authorized Signatory

       [SIGNATURE PAGE TO AMENDMENT NO. 1 TO FIRST LIEN CREDIT AGREEMENT]

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                              CONSENT OF GUARANTORS

                                                         Dated as of May 5, 2006

          Each of the undersigned companies, as a Guarantor under the Guaranty
dated February 6, 2006 (the "Guaranty") in favor of the Secured Parties under
the Credit Agreement referred to in the foregoing Amendment, hereby consents to
such Amendment and hereby confirms and agrees that notwithstanding the
effectiveness of such Amendment, the Guaranty is, and shall continue to be, in
full force and effect and is hereby ratified and confirmed in all respects,
except that, on and after the effectiveness of such Amendment, each reference in
the Guaranty to the "Credit Agreement", "thereunder", "thereof" or words of like
import shall mean and be a reference to the Credit Agreement, as amended by such
Amendment.

                            [Signature pages follow]

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          IN WITNESS WHEREOF, the parties hereto have consented to this
Amendment No. 1, as of the date first written above.

                                     CONVERGENT TECHNOLOGIES INTERNATIONAL, INC.
                                     TECUMSEH TRADING COMPANY
                                     EVERGY, INC.
                                     FASCO INDUSTRIES, INC.
                                     MANUFACTURING DATA SYSTEMS, INC.
                                     M. P. PUMPS, INC.
                                     TECUMSEH CANADA HOLDING COMPANY
                                     TECUMSEH COMPRESSOR COMPANY
                                     TECUMSEH POWER COMPANY
                                     VON WEISE GEAR COMPANY
                                     as U.S. Guarantors


                                     By: /s/ JAMES S. NICHOLSON
                                         ---------------------------------------
                                     Name: James S. Nicholson
                                     Title: Vice President and Treasurer


                                     EUROMOTOR, INC.
                                     as U.S. Guarantor


                                     By: /s/ JAMES S. NICHOLSON
                                         ---------------------------------------
                                     Name: James S. Nicholson
                                     Title: Vice President


                                     HAYTON PROPERTY COMPANY, LLC
                                     TECUMSEH DO BRASIL USA, LLC
                                     as U.S. Guarantors


                                     By: /s/ JAMES S. NICHOLSON
                                         ---------------------------------------
                                     Name: James S. Nicholson
                                     Title: President


                                     TECUMSEH PRODUCTS OF CANADA LIMITED,
                                     as Canadian Guarantor


                                     By: /s/ JAMES S. NICHOLSON
                                         ---------------------------------------
                                     Name: James S. Nicholson
                                     Title: Vice President


                                     FASCO MOTORS COMPANY,
                                     as Canadian Guarantor


                                     By: /s/ JAMES S. NICHOLSON
                                         ---------------------------------------
                                     Name: James S. Nicholson
                                     Title: Vice President

             [SIGNATURE PAGE TO GUARANTOR CONSENT TO AMENDMENT NO. 1
                        TO FIRST LIEN CREDIT AGREEMENT]