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Discussion Starter #1
Checked my valves today - all good as far as clearances go. But when I put it back together the front tappet cover is leaking badly. I took it back off, made sure both surfaces and the o ring were clean, flipped the o ring over, and it's still dripping. This is a long weekend so I won't be able to get a new o ring until Tuesday. I'm wondering if I could use RTV or something like it to get by until I can fix it properly.
 

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Super Moderator "Loose Nut"
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You will get mixed answers on this. I do put a thin coat of RTV on mine. Has never leaked and no issues using it. The one thing you want to avoid is getting RTV on the inside of cover. A small piece could get into an oil passage causing major oil flow issue.
 

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just replaced a leaky o ring on my 650: $6 at dealer. Simple, no fuss, worked perfect.

how badly is it leaking? you have to clean it off again anyway, so maybe you can just get away with riding it for a couple days.

Mine had been leaking a bit for a couple months before I checked the valves, soaped up everything and cleaned it all off, and then was able to see it was oozing from the rear tappet cover. It was only enough to leave a couple drips on the garage floor in 2 months. I though it was the drive shaft engine seal, so I was happy as can be to replace a $6 o ring on the tappet cover.
 

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Discussion Starter #4
This is a serious enough leak that it can't be driven. I've had issues with RTV before with another bike doing exactly what lesblank described so I'm a little hesitant to try it again. I have no problem buying the o ring, except that the dealer is closed until Tuesday (long weekend here in NB). I was looking through my stash of various tubes and it looks like I'm out of RTV anyway so I guess it'll have to wait. Next time I'll have o rings in stock before I start.
 

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Discussion Starter #5
Well, found the problem and as we say in the trucking business, it was driver error. Turned out it wasn't the front exhaust cover that was leaking, but the intake. Oil was running down through the fins and around to the front, dripping from the front cover so it looked like it was the one leaking. The problem was that there is a wire loom holder that fastens to one of the two screws on the intake cover and like a bonehead I put it between the cover and the cylinder instead of under the head of the screw (yeah, yeah, still shaking my head). Anyway, got it all fixed up and aside from a little oil leakage all is good again. Took a lot less time to tear it down this time - practice makes perfect! lol
 

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NorthernRider, I can relate to "driver error", been there more than I like to admit. Just glad you got it figured out. Just chalk it up as a good learning experience. It's funny how that oil seems to have a mind of it's own.
 

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Oil has such high adhesion when you get it on a hot engine it wicks out in all directions, and its hard to tell where its really coming from.

It did seem odd that an o ring would leak so much that you could not ride the bike - if the o ring was that bad, it would have looked like a piece of rope.
 

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Discussion Starter #8
Yeah, I thought it looked too good to leak that bad too. If it looked that bad I wouldn't have put it back together without a new one. As soon as I saw the wiring loom I knew I'd found the problem. Had it to work and back today and aside from a little oil smell where it seeped into some cracks and crevices, the there's no more signs of a leak. Appreciate the help and advice.
 
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