Small problem with an "O" ring seal

[Panzer]

How do you keep the oil drain plug "O"ring from squishing out when you tighten the drain plug?
I've tried different size "O" rings to no avail........any suggestions?

[tmwmoose]

When the hole is machined and threaded there's a small chamfer at the entrance for the o ring and after some time usually overtightening, the threads pull out a bit and you lose the chamfer. I stayed at a Holiday inn express last night

[Panzer]

When the hole is machined and threaded there's a small chamfer at the entrance for the o ring and after some time usually overtightening, the threads pull out a bit and you lose the chamfer. I stayed at a Holiday inn express last night

Treads are good, never over tightened.
It's just that the "O" ring wants to roll out when I go to tighten the plug. 

We'll leave the light on for ya.  :   

[tmwmoose]

Well what ever the cause then, the fact is that you don't have a recess for the o ring to be captured in so now you have two flat surfaces meeting were is the o ring sits  your o ring has no choice but to be squeezed out

[Panzer]

Gotcha......ok.

[FSG]

Crankcase or Primary?

Your Primary uses Plug 60328-98B with O-Ring 11105, if there's no recess in the bottom of the primary for the o-ring then I'd either make one OR ditch the o-ring for a copper washer(s).

[Panzer]

Chaincase.............sorry.
Had "O" ring when the bike was new so it has to have a recess.
I've tried a couple of different ones.......nada. 

[tmwmoose]

Try some auto parts joints or better yet McCaster Carr and find a hard nylon washer that fits snug as possible on the plug . If it was me I'd go see my machinist bud and see what he had in a large ass drill bit with a fairly steep angle and cut/refresh the relief turning the bit by hand .Be nice if one of those unibit drills had a size that fit good in the hole with the next step just right for a relief cut, just thinking
Just remembered McCaster has washers that have o rings fixed in the id in different sizes HD use to use them on the first EVO wet clutch derby cover screws

[cyclobutch]

Switch to a Dowty Washer?

[Panzer]

Switch to a Dowty Washer?

I call them oil seals..........