Re: Clutch Plug Removal on AP 900

Don Anderson

Hello George
I have never changed the plugs on my 2009 AP900GOTO. They seem to be working well at this point. Should I change them out because of age? Do they get brittle with time?

Don Anderson

On Monday, April 6, 2020, 07:53:04 a.m. MDT, George <george@...> wrote:



You are correct.   An extractor is an alternative extraction technique.   As you point out, sizing it correctly is important.   There have been sveral customers who have used it successfully.  


Unfortunately, I am working from home and I can’t give you a hole size for the plug, but will be able to do so the next time someone needs to extract the plugs.






George Whitney

Astro-Physics, Inc.

Phone:  815-282-1513

Email:  george@...


From: [] On Behalf Of Michael Hambrick via
Sent: Saturday, April 04, 2020 7:42 PM
Subject: Re: [ap-gto] Clutch Plug Removal on AP 900


Hi Robert

I am glad you were able to remove the old clutch plugs.

This is really a question for George or Roland, but after reading your description of the plug removal process I am wondering if anyone has ever tried using a screw extractor to get of the clutch plugs out. These devices are used in automotove repair shops and machine shops. They are very tricky to use, but if done correctly they will help the shop owner avoid having to do a major repair job on an engine block or cylinder head.

There are several tricks to getting a screw extractor to work:

  1. Use the correct size extractor for the screw thread size
  1. You have to drill the correct size hole in the broken screw.
  1. Don't use too much force to turn the extractor. They are made from hardened tool steel, and they are very brittle. If you break one off in the screw you are totally out of luck.

Since the clutch plugs already have a hole drilled in them, 2/3 of the work is already done. Next, you tap the screw extractor into the hole until the flutes dig into the hole and then turn it counterclockwise while pushing down on it using a T-handle tap wrench to grip the square head of the screw extractor. The counterclockwise turning motion causes the screw extractor to grip the hole very firmly allowing it to turn the broken screw along with it.

I DO NOT recommend trying to do this unless Roland or George sanction doing so. As both of them seem to be very mechanically inclined, I expect that they have probably tried this technique before.

Best Regards

Michael Hambrick

TSR Global Manufacturing Support
PO Box 2000
Orange, TX 77631-2000
Phone: +1 (409) 882-2799
email: mike.hambrick@...

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