Snapped Off Oil Filler Cap

[Can_O_Tuna]

Dumb A$$ me. I took off my tank on Tuesday to get to my horn and I put my petcock on PRIME to get a quick restart. Guess who forgot to put it back to RUN? My overflow tube did its job and I had a nice puddle of gas on the garage floor today. I checked the oil thru the window and it did not appear to overfull with gas. Just to make sure I went to take off the oil filler cap and take a peek inside. Instead of using the clamp style pliers I have been using for years with no problems, I used a pair of regular vice grips....and snapped the bastage off. I must have snugged it a bit too tight and I did a lot of polishing yesterday...between the 2 it is really stuck on. I hit it with PB blaster and I will go out in a while to see if I can get it off..... Anybody done this? Or have I invented a new category of another thing not to do?

[Hoomgar]

I've had them on tight already and often have to use a tool to get them off but I have never seen this one yet Jim

I always use an adjustable wrench. You can snug it up and get a good square bite on the whole flange that way.
You may still be able to use an adjustable to get that off from the way it looks?

[Jethro]

Worst case, use a drift and hammer it on the right flange. Keep the drift at a good angle, pointing towards the flange.

Kudos for you for posting the pictures. I would be too ashamed!!

[Boondocks]

I've never tightened my oil filler cap more than finger tight, and it has never loosened. Note that it doesn't have a nut or other device commonly used to mechanically tighten a fastener. Note also that there is no torque rating for the cap, because it is designed to be finger tightened using the flange.

[onchiman]

Mine was getting really difficult to remove even when just finger tightened. I wondered if it had something to do with the o-ring seal on the cap getting old so I bought a new one from the hardware store. For me this solved the issue completely. I can now feel the o-ring make contact and compress a bit and it's been easy to remove ever since. I don't know if this will help you but it might. I've never used a wrench of any kind on mine.

[relic-rider]

Thats the advantage of o-ring seals. You don't have to torque down on them a lot for a good seal. Finger tight should do. I don't know why it took American manufacturers so long to figure this out, especially on car or truck valve covers. The large o-ring seal on my Toyota truck valve cover has never leaked, while the crappy cork seals on my 72 Chev pickup are a constant mess. Keeping the rubber lubed is a key to their long life, since when they dry out they flatten and leak, ie: intake boot o-rings. They do tend to stick a little with age. Look at your car spin on oil filter. You hand tighten it initially, but how many of us can unscrew it after 3500 miles. You pretty much need a wrench by then.

[Deesel]

Righty tighty, lefty loosey???

[Can_O_Tuna]

Mine was getting really difficult to remove even when just finger tightened. I wondered if it had something to do with the o-ring seal on the cap getting old so I bought a new one from the hardware store. For me this solved the issue completely. I can now feel the o-ring make contact and compress a bit and it's been easy to remove ever since. I don't know if this will help you but it might. I've never used a wrench of any kind on mine.

That is probably the ultimate cause. A new o-ring would not have sealed as tight as this one was. In addition I had 2 cylinders with gas in them..... The bulk of the gas did not get into the oil, but I took all my plugs out and and #2 cylinder was full of gas. I put the bike outside when I saw the leak, and it was in the mid-eighties here today and I think (I could be wrong) I got enough expansion with the raw fuel in the cylinders ( and the intakes I think) to make a bit of a lock. I waited to drain all of the oil until after I drained the gas out of the bowls and the cylinder and the cap came off as if it was only just a bit tighter than finger tight (normal) with an adjustable wrench (thanks Hoom). Thanks to the forum as well… I learned to check EVERYTHING before trying to start a motor flooded with gas here.

[robinjo]

Note that it doesn't have a nut or other device commonly used to mechanically tighten a fastener. Note also that there is no torque rating for the cap, because it is designed to be finger tightened using the flange.

:mrgreen:

That's what I thought too.