Primary drain plug thread size : V-Twin Forum: Harley Davidson Forums

TERMINKNOTTER · 10-29-2009, 01:55 PM

Anyone know what size the drian plug tread is on a 01 touring bike ? The plug on my girls Road King doesn't seem to thread in as far as it should. Want to chase the threads but would prefer to have the tap on hand, save the trouble of running out to get it.

Thanks

springer- · 10-29-2009, 02:08 PM

Are you asking about the primary or the oil pan? If the oil pan, this might help ... http://www.bigboyzheadporting.com/showthread.php?t=85 They make oversize plugs to repair a stripped out hole.

hbmc · 10-29-2009, 04:07 PM

measure the thread size of the plug??? use a die to thread it on and use the corresponding tap to chase it thru

Ed Y · 10-29-2009, 11:49 PM

Primary drain plug on an 01 is a pipe thread. It's not designed to thread all the way in. If I remember correctly, it's a 1/8 pipe thread.

TERMINKNOTTER · 10-30-2009, 08:11 AM

Primary drain plug.

On my 03 RKC plug screws in pretty far, service manual spells out amount of plug to leave exposed. On her 01 RK, manual doesn't give any info, and the plug doesn't seem to go in far enough. Was leaking, seems to have finally stopped(after aweek or two and 1000 mile road trip).

Just don't want to screw it in too far. Thought the treads might be buggered up. This is the first I've done any work on her bike.

LADave · 10-30-2009, 08:52 AM

Quote:

Originally Posted by TERMINKNOTTER

Primary drain plug.

On my 03 RKC plug screws in pretty far, service manual spells out amount of plug to leave exposed. On her 01 RK, manual doesn't give any info, and the plug doesn't seem to go in far enough. Was leaking, seems to have finally stopped(after aweek or two and 1000 mile road trip).

Just don't want to screw it in too far. Thought the treads might be buggered up. This is the first I've done any work on her bike.

If it just stopped leaking on its own, first thing I would do is check the fluid level in the primary. Make sure there's still plenty in there. These things don't just heal themselves...

On to the drain-plug...
First, you might just pull it out and give it a visual inspection to see what kind of condition its in (this will be a good time to change the primary fluid) If the threads on the plug are boogered up, compare it to the closest tap you can. Either 1/8-inch NPT or maybe something else, and go from there...

If nothing is boogered up, you can coat it with a dab of pipe-dope or put a few wraps of Teflon tape around it or even a very small dab of silicone. I emphasize "Dab" because a lot of people like to really goop on the silicone. Don't make that mistake. A very light coating on the first few threads should be more than enough.

I don't know if is a pipe thread or not. But, if it is, they are tapered a bit. Tightening it up a bit, shouldn't cause problems. Not unless you go crazy with it and strip the threads.

When I have to R & R the primary cover, I tighten it, until it feels snug. If that don't keep it from leaking, Tape, pipe-dope or a dab of silicone, which ever is handy...

Ed Y · 10-30-2009, 02:01 PM

I always use "thread sealant with Teflon".

hbmc · 10-30-2009, 02:20 PM

Quote:

Originally Posted by Ed Y

Primary drain plug on an 01 is a pipe thread. It's not designed to thread all the way in. If I remember correctly, it's a 1/8 pipe thread.

yep that is right.... Now I think about it--- it is designed to snug up in there with some teflon tape. And so need to be replaced every so often as the threads are designed to collapse before the cover does.