DOHC engine, leaking around cam shaft 'caps'

[DanMach]

I have an 82 xs400j. I noticed today before I went for a ride the oil was a touch lower, so I topped it off and went to work. Got to work and noticed the the black half moon caps on the valve cover had oil beneath them and some was sitting on the engine itself. Maybe a teaspoon total? But I know some burnt off(i was on the freeway and its hard to notice but in retrospect I feel sure it was burning a touch on the engine).
So I'm trying to think what I can do about it now. I recently, within last week or so, have been doing a lot more freeway riding. Between 6200 and 7000RPM's roughly for stints of about 15-20 miles.

I use to do similiar rides on this bike last year and I never had this issue, so I think its something new. Probably caused from when I went to adjust the valves a few months ago. Should I just double check the caps are seated properly? Do I get some kind of sealant for it? Any ideas??

Thanks!

 

[bentwrench]

Check the caps, yes. Also, get thee a new valve cover gasket. Did you replace it when you adjusted the valves? What kind of shape was it in?

 

[DanMach]

I knew you'd reply, figured I should do it in public for historys sake. Anyways, the valve cover gasket was in perfect shape. Not a defect in it, I inspected it pretty damn close too. I did examine that seal, between valve cover and engine, and it was spotless. The caps are where the oil is leaking from. I'm still at work but when I get out I'll see if they are fully pressed in and everything. Oil level is still above the minium mark in the window so no big deal getting home. I'll update later with what happens...

Thanks!

 

[bentwrench]

Hmmm... Did you torque down the bolts to spec?

 

[DanMach]

All the ones except for the two inner rear ones(near the rear monoshock) because I couldn't get a torque wrench anywhere near those. Hmm.. I didn't think about that! While I doubt it could cause a leak, its still worth checking!

 

[bentwrench]

If they're inner rear, they shouldn't cause a problem near the caps.

I'm interested in other's opinions, because I'm down to "use liquid gasket."

I was thinking about those caps just the other day, as I'm not entirely sure why they're there. Why include holes in the tops of the engine, if you're just going to put a cheap piece of rubber there?

 

[DanMach]

Sooo... big shocker here, but I'm pretty sure you were right. I just went out there and retorqued everything to find that a few of the outter screws were actually fairly loose. I know I tightened them... but I think heat cycles and vibrations have loosened them. I'll have to key a close eye on that for a while. I took a decent flash light out there and saw that some oil was leaking from the front of the engine's valve cover gasket. So I retorqued everything I could, and what I couldn't I hand tightened down(inner ones mostly).

I'll post a follow up either tomorrow or the day after to let everyone know what happened.

Thanks again man!!

 

[DanMach]

Well that was it. Rode into work today and some mild cruising before work, about 30 miles or so over about 45 minutes(fuck traffic.), and everything was fine when I got to work.

 

[bentwrench]

Nice! I like it when a fix doesn't cost any money.