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                                                                    EXHIBIT 4.13

                               FOURTH AMENDMENT TO
                       CREDIT AND INTERCREDITOR AGREEMENT
                       ----------------------------------

         THIS FOURTH AMENDMENT TO CREDIT AND INTERCREDITOR AGREEMENT, dated as
of August 3, 1998 (this "Amendment"), among CASTING TECHNOLOGY COMPANY, an
Indiana general partnership (the "Company"), NBD BANK, N.A., a national banking
association (successor by assignment to NBD Bank, a Michigan banking
corporation) ("NBD"), and THE ASAHI BANK, LTD., a Japanese banking corporation
acting through its Chicago Branch ("Asahi") (NBD and Asahi, collectively, the
"Banks" and individually, a "Bank"), and NBD BANK, N.A., a national banking
association, as agent for the Banks (in such capacity, the "Agent").

                                    RECITALS
                                    --------

         A. The parties hereto have entered into a Credit and Intercreditor
Agreement dated July 28, 1995 (as amended, the "Credit Agreement"), which is in
full force and effect.

         B. The Company desires to amend the Credit Agreement as herein
provided, and the Banks and the Agent are willing to so amend the Credit
Agreement on the terms set forth herein.

                                    AGREEMENT
                                    ---------

         Based upon these recitals, the parties agree as follows:

         1. AMENDMENT. Upon the effective date of this Amendment, the Credit
Agreement shall be amended as follows:

         Section 5.2(a) of the Credit Agreement is amended by adding the
following paragraph to the end of such subsection:

                  Notwithstanding anything else contained in this Agreement, the
                  Company may incur Indebtedness to the Partners or the
                  Guarantors, or any of them, in aggregate principal amount not
                  to exceed Six Million Dollars ($6,000,000) at any one time
                  outstanding, and make payments of principal and interest
                  thereon (irrespective of the limitations contained in Section
                  5.2(h)), PROVIDED that, upon the occurrence and during the
                  continuance of any Default or Event of Default, all such
                  Indebtedness to the Partners or the Guarantors shall be
                  subordinated to all Indebtedness now or hereafter owing by the
                  Company to the Banks until all Indebtedness owing by the
                  Company to the Banks has been irrevocably paid in full.

         2. REFERENCES TO CREDIT AGREEMENT. From and after the effective date of
this Amendment, references to the Credit Agreement in the Credit Agreement and
all other documents issued under or with respect thereto (as each of the
foregoing is amended hereby or pursuant hereto) shall be deemed to be references
to the Credit Agreement as amended hereby.

         3. REPRESENTATIONS AND WARRANTIES. The Company represents and Warrants
to the Banks and the Agent that:

         (a)      (i) The execution and delivery by the Partners on behalf of
                      the Company and



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the performance by the Company of this Amendment and all agreements,
instruments, and documents delivered pursuant hereto by the Company have been
duly authorized by all necessary action and do not and will not violate any
provision of any law, rule, regulation, order, judgment, injunction, or award
presently in effect applying to the Company, or of the Company's charter, or
result in a breach of or constitute a default under any material agreement,
lease or instrument to which the Company is a party or by which it or its
properties may be bound or affected; (ii) no authorization, consent, approval,
license, exemption or filing of a registration with any court or governmental
department, agency or instrumentality is or will be necessary to the valid
execution, delivery or performance by the Company of this Amendment and all
agreements and documents delivered pursuant hereto; and (iii) this Amendment and
all agreements and documents delivered pursuant hereto by the Company are the
legal, valid and binding obligations of the Company, enforceable against it in
accordance with the terms thereof.

         (b) After giving effect to the amendments contained herein, the
representations and warranties contained in Article IV (other than Section 4.6)
of the Credit Agreement are true and correct on and as of the effective date
hereof with the same force and effect as if made on and as of such effective
date.

         (c) No Default or Event of Default has occurred and is continuing or
will exist under the Credit Agreement as of the effective date hereof.

         4. MISCELLANEOUS. The terms used but not defined herein shall have the
respective meanings ascribed thereto in the Credit Agreement. Except as
expressly amended hereby, the Credit Agreement and all other documents issued
under or with respect thereto are hereby ratified and confirmed by the Banks,
the Agent, and the Company and shall remain in fall force and effect, and the
Company acknowledges that it has no defense, offset or counterclaim with respect
thereto.

         5. COUNTERPARTS. This Amendment may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument and any of the parties hereto may execute this Amendment by signing
any such counterpart.

         6. EXPENSES. The Company agrees to pay and save the Agent and the Banks
harmless from liability for all costs and expenses of the Agent and the Banks
arising in respect of this Amendment, including the reasonable fees and expenses
of the respective counsel to the Agent and the Banks in connection with
preparing and reviewing this Amendment and any related agreements and documents.

         7. GOVERNING LAW. This Amendment is a contract made under, and shall be
governed by and construed in accordance with, the laws of the State of Michigan
applicable to contracts made and to be performed entirely within such state and
without giving effect to the choice law principles of such state.



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         IN WITNESS WHEREOF the parties hereto have caused this Amendment to be
duly executed and delivered as of the date first written above.


                                       CASTING TECHNOLOGY COMPANY
                                       By:  AMCAST CASTING TECHNOLOGIES, INC.,
                                       Its General Partner

                                       By: /s/ John H. Shuey
                                          --------------------------------------
                                            John H. Shuey
                                            Its: President

                                       And By: IZUMI, INC.,
                                         its General Partner


                                       By: /s/ Tomoaki Izumi
                                          --------------------------------------
                                            Tomoaki Izumi
                                            Its: Vice President & CEO
                                                
                                       AMCAST CASTING TECHNOLOGIES, INC.,
                                        individually

                                       By: /s/ John H. Shuey
                                          --------------------------------------
                                            John H. Shuey
                                            Its: President

                                       IZUMI, INC.,
                                       individually

                                       By:
                                          --------------------------------------

                                            Its:
                                                ----------------------
 
                                       NBD BANK, N.A., individually and as Agent

                                       By: /s/ Edward C. Hathaway
                                          --------------------------------------
                                            Edward C. Hathaway
                                            Its: First Vice President


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