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                                                                     Exhibit 4.6


                            THIRD AMENDMENT AGREEMENT

         This Third Amendment Agreement (this "Amendment") is made as of the
15th day of March, 2000, among PARK-OHIO INDUSTRIES, INC., an Ohio corporation
("Borrower"), the banking institutions listed on SCHEDULE 1 to the Credit
Agreement, as hereinafter defined ("Banks"), KEYBANK NATIONAL ASSOCIATION, as
administrative agent for the Banks ("Administrative Agent"), and THE HUNTINGTON
NATIONAL BANK, as co-agent for the Banks ("Co-Agent" and, together with
Administrative Agent, "Agents").

         WHEREAS, Borrower, Agents and the Banks are parties to a certain
Amended and Restated Credit Agreement dated as of November 2, 1998, as amended
and as the same may from time to time be further amended, restated or otherwise
modified, which provides, among other things, for loans aggregating One Hundred
Seventy-Five Million Dollars ($175,000,000), all upon certain terms and
conditions (the "Credit Agreement");

         WHEREAS, Borrower, Agents and the Banks desire to amend the Credit
Agreement to modify certain other provisions thereof; and

         WHEREAS, each term used herein shall be defined in accordance with the
Credit Agreement.

         NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein and for other valuable considerations, Borrower, Agents and the
Banks agree as follows:

         1. Section 5.7 of the Credit Agreement is hereby amended to delete
subsection (c) therefrom and to insert in place thereof the following:

                  (c) LEVERAGE RATIO. Borrower shall not suffer or permit at any
         time the Leverage Ratio to exceed:

                           (i) 5.00 to 1.00 for the period from the Closing Date
                  through December 30, 1999 at any time that the Leverage Ratio
                  Condition exists during such period;

                           (ii) on December 31, 1999 through March 30, 2000,
                  5.00 to 1.00 or, in the event that the Tranche D Leverage
                  Ratio Condition exists, 4.50 to 1.00;

                           (iii) on March 31, 2000 through June 29, 2000, 5.00
                  to 1.00;

                           (iv) on June 30, 2000 through September 29, 2000,
                  5.00 to 1.00 or, in the event that the Tranche D Leverage
                  Ratio Condition exists, 4.75 to 1.00; provided, however, that,
                  if, on June 30, 2000, the Tranche D Leverage Ratio Condition
                  exists and the Leverage Ratio is greater than 4.75 to 1.00 but
                  less than 5.00 to 1.00, then an Event of Default shall not be
                  deemed to have occurred under this Agreement by virtue of the
                  breach of this subpart (iv) of this Section 5.7(c) so long as
                  the ratio for Borrower of (A) Total Funded Indebtedness
                  (outstanding on July 31, 2000) to (B)

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                  Consolidated Pro-Forma EBITDA (based upon the financial
                  statements of Borrower for the fiscal quarter ended June 30,
                  2000 and the three (3) previous fiscal quarters) is less than
                  4.75 to 1.00 on July 31, 2000; and

                           (v) on September 30, 2000 and thereafter, 5.00 to
                  1.00 or, in the event that the Tranche D Leverage Ratio
                  Conditions exists, 4.00 to 1.00.

         2. The Credit Agreement is hereby amended to delete Section 7.9
therefrom in its entirety and to insert in place thereof the following:

                  SECTION 7.9. DESIGNATED SENIOR INDEBTEDNESS . If any Company
         shall incur or permit to exist any Designated Senior Indebtedness (as
         defined in the Indenture) other than the Debt.

         3. Borrower, Agents and the Banks agree that, notwithstanding any
provision of the Credit Agreement to the contrary, no Subsidiary shall (a)
become a Guarantor with respect to any of the Indebtedness incurred in
connection with the Senior Subordinated Notes, (b) merge with Borrower, or (c)
sell, lease, transfer or otherwise dispose of all or a substantial part of its
assets to Borrower.

         4. Borrower, Agents and the Banks agree that, notwithstanding any
provision of the Credit Agreement to the contrary, if the Tranche D Leverage
Ratio Condition exists (or immediately after consummating any Acquisition would
exist), no Acquisition otherwise permitted pursuant to Section 5.13 of the
Credit Agreement, shall occur during the period from the date of this Amendment
through September 30, 2000 (the "Restricted Period") unless the Leverage Ratio,
both before and after consummating such Acquisition, is less than or equal to
(a) 4.50 to 1.00 for the period from the date of this Amendment through June 29,
2000, and (b) 4.00 to 1.00 thereafter. In the event that, without the prior
written consent of Agents and the Banks, an Acquisition shall occur during the
Restricted Period in violation of the preceding sentence, such Acquisition shall
constitute an Event of Default under the Credit Agreement.

         5. Concurrently with the execution of this Amendment, Borrower shall:

         (a) cause each Guarantor of Payment to consent and agree to and
acknowledge the terms of this Amendment;

         (b) pay an amendment fee to (i) Administrative Agent, for its own
account, in the amount of Twenty-Five Thousand Dollars ($25,000) and (ii)
Co-Agent, for its own account, in the amount of Ten Thousand Dollars ($10,000);
and

         (c) pay all legal fees and expenses of Administrative Agent in
connection with this Amendment.




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         5. Borrower hereby represents and warrants to Agents and the Banks that
(a) Borrower has the legal power and authority to execute and deliver this
Amendment, (b) the officers executing this Amendment have been duly authorized
to execute and deliver the same and bind Borrower with respect to the provisions
hereof, (c) the execution and delivery hereof by Borrower and the performance
and observance by Borrower of the provisions hereof do not violate or conflict
with the organizational agreements of Borrower or any law applicable to Borrower
or result in a breach of any provision of or constitute a default under any
other agreement, instrument or document binding upon or enforceable against
Borrower, (d) no Unmatured Event of Default or Event of Default exists under the
Credit Agreement, nor will any occur immediately after the execution and
delivery of this Amendment or by the performance or observance of any provision
hereof, (e) Borrower is not aware of any claim or offset against, or defense or
counterclaim to, any of Borrower's obligations or liabilities under the Credit
Agreement or any Related Writing, and (f) this Amendment constitutes a valid and
binding obligation of Borrower in every respect, enforceable in accordance with
its terms.

         6. Each reference that is made in the Credit Agreement or any other
writing to the Credit Agreement shall hereafter be construed as a reference to
the Credit Agreement as amended hereby. Except as herein otherwise specifically
provided, all provisions of the Credit Agreement shall remain in full force and
effect and be unaffected hereby. This Amendment is a Related Writing as defined
in the Credit Agreement.

         7. Borrower and each Guarantor of Payment, by signing below, hereby
waives and releases Administrative Agent, Co-Agent and each of the Banks and the
respective directors, officers, employees, attorneys, affiliates and
subsidiaries of each of the foregoing from any and all claims, offsets, defenses
and counterclaims of which Borrower or such Guarantor of Payment is aware, such
waiver and release being with full knowledge and understanding of the
circumstances and effect thereof and after having consulted legal counsel with
respect thereto.

         8. This Amendment may be executed in any number of counterparts, by
different parties hereto in separate counterparts and by facsimile signature,
each of which when so executed and delivered shall be deemed to be an original
and all of which taken together shall constitute but one and the same agreement.

         9. The rights and obligations of all parties hereto shall be governed
by the laws of the State of Ohio, without regard to principles of conflicts of
laws.

                  [Remainder of page intentionally left blank.]




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         10. JURY TRIAL WAIVER. BORROWER, AGENTS AND EACH OF THE BANKS WAIVE ANY
RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
CONTRACT, TORT OR OTHERWISE, AMONG BORROWER, AGENTS AND THE BANKS, OR ANY
THEREOF, ARISING OUT OF, IN CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED AMONG THEM IN CONNECTION WITH THIS AGREEMENT OR ANY
NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS RELATED THERETO. THIS WAIVER SHALL NOT
IN ANY WAY AFFECT, WAIVE, LIMIT, AMEND OR MODIFY AGENTS' OR ANY BANK'S ABILITY
TO PURSUE REMEDIES PURSUANT TO ANY CONFESSION OF JUDGMENT OR COGNOVIT PROVISION
CONTAINED IN ANY NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT AMONG BORROWER,
AGENTS AND THE BANKS, OR ANY THEREOF.

                                           PARK-OHIO INDUSTRIES, INC.

                                               /s/ James S. Walker
                                           By: _________________________________
                                               James S. Walker, Vice President


                                           and /s/ Ronald J. Cozean
                                               _________________________________
                                               Ronald J. Cozean, Secretary


                                           KEYBANK NATIONAL ASSOCIATION,
                                           as a Bank and as Administrative Agent

                                               /s/ Kenneth M. Merhar
                                           By: _________________________________
                                               Kenneth M. Merhar, Vice President

                                           THE HUNTINGTON NATIONAL BANK,
                                            as a Bank and as Co-Agent

                                               /s/ Timothy M. Ward
                                           By: _________________________________
                                               Timothy M. Ward, Vice President




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                            GUARANTOR ACKNOWLEDGMENT
                            ------------------------

         Each of the undersigned consents and agrees to and acknowledges the
terms of the foregoing Third Amendment Agreement. Each of the undersigned
further agrees that the obligations of the undersigned pursuant to the Guaranty
of Payment executed by the undersigned shall remain in full force and effect and
be unaffected hereby.

                                      ADVANCE VEHICLES, INC.
                                      BLUE FALCON FORGE, INC.
                                      CASTLE RUBBER COMPANY
                                      CICERO FLEXIBLE PRODUCTS, INC.
                                      COLUMBIA NUT & BOLT CORP.
                                      GIS INDUSTRIES, INC. (formerly known as
                                        Charken Company, Inc.)
                                      GENERAL ALUMINUM
                                           MANUFACTURING COMPANY II
                                      GENERAL ALUMINUM MFG. COMPANY
                                      GENEVA RUBBER COMPANY
                                      INDUSTRIAL FASTENERS CORPORATION
                                      INTEGRATED LOGISTICS SOLUTIONS, INC.
                                      INTEGRATED LOGISTICS SOLUTIONS LLC
                                       (successor by merger to Arden
                                       Industrial Products, Inc.)
                                      INTEGRATED LOGISTICS HOLDING COMPANY
                                      KAY HOME PRODUCTS, INC.
                                      PARK-OHIO STRUCTURAL HARDWARE LLC
                                      PHARMACEUTICAL LOGISTICS, INC.
                                      PHARMACY WHOLESALE LOGISTICS, INC.
                                      RB&W MANUFACTURING LLC (successor
                                        by merger to RB&W Corporation)
                                      THE AJAX MANUFACTURING
                                        COMPANY
                                      THE METALLOY CORPORATION
                                      TOCCO, INC.

                                          /s/ James S. Walker
                                      By: ____________________________________
                                          James S. Walker, Vice President
                                          of each of the foregoing Companies


                                          /s/ Ronald J. Cozean
                                      By: ____________________________________
                                          Ronald J. Cozean, Secretary
                                          of each of the foregoing Companies



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