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Stuck Differential Filler Plug

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Robert Spitz
Posts: 4
Active Member
Topic starter

Bike has been sitting a long time.  Differential filler plug is stuck.  Tips on how to free up without wrecking the threads in the case?

Posted : 03/30/2023 11:08
James Strickland
Posts: 421
Reputable Member

If it were my bike, I would apply several soakings of a liquid penetrant. A 50/50 blend of acetone and automatic transmission fluid (ATF) works well, but there are other products available at auto parts stores like NAPA. After a few days of application and soaking I would use a manual impact driver, the kind you whack with a hammer, to deliver a shock wave and a slight twist.  If that did not work, I would use a torch to heat up the part of the casting where the plug resides. If you have to resort to that kind of operation after using a penetrant, you can expect a bit of a flame up from residual penetrating fluid.  Manual impact drivers can be set to twist in both directions, so be careful about that. You wouldn't want to drive the fill plug in even tighter. 

best of luck 

former Airmarshal, IL.

Posted : 03/31/2023 07:53
Joe Hall reacted
Robert Spitz
Posts: 4
Active Member
Topic starter

@8053 Thanks James.


Posted : 03/31/2023 15:11


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