Tachometer Drive Plug Seal

[nucklhead13]

I got an 80 thousands CC Ironhead and I've been working to get rid of every oil leak After I beat the oil line seals I discovered another leak. The stock tachometer has been replaced with a Tachometer Drive Plug. On line one can see some for sale. Those generally have a gasket. They look like some kind of thin washer. There is nothing left on mine so I ned to learn what goes there so I can either make one or get by using some silicon. What gets used some kind of copper or fibre washer?

[garyajaz]

I did not buy a cap plug for mine. none sold back then.
just some capped nut. I put a fiber washer under it.
been on for 30 or so years.
I would actually like a tach but when one of my cams left it broke up that part of the case.
good luck chasing leaks.
only one I have now is a drop or so from the crank breather.  was thinking of a catch can cause when ever I go to some event people always trying to find leaks.
kinda like with craigs pan.  when I see his i ask if he running it without oil.

keep chasing.

[nucklhead13]

I had a clue yesterday. See I use Permatex on the fittings that screw into the home-made oil tank. I bet that is why there wasn't any worn-out gasket at all. Thirteen equals good luck.

[nucklhead13]

Yes I had tried a fibre washer given to me at a hardware store. That had made things worse. Today, after looking through my coffee can of washers for one that might work I hit an auto parts shop and got a 11/16 M 18 copper oil tite washers. That didn't pass the test with a straight A. It just cut the leak back a whole lot. Now I need to find out how much one torques the plug to. I sure don't want to tear things up just guessing. Yes I had only tightened it up until it felt tight enough.

[nucklhead13]

Mechanical combat takes perseverance. It helped to look the plug over and find out how far in the cover the threads for it start. That helped me learn it takes a rubber O ring on the plug above the threads and below the thick part. That way it seals when the plug is tightened up. One just has to hunt around to find one that is the right size.