Valve Cover Oil Weep

[PaulM]

Hi guys,

I just wondered if anyone has had the issue I've had with my valve cover on my '89 EXUP. I have always suffered with a very slight oil weep at the very front of the valve cover. Nothing major just a small weep that burns off as soon as the engine gets hot. After doing my valve shims, I came to fit the valve cover with a new gasket and noticed something. The exhaust-side timing nylon chain guide seemed to be very slightly protruding above the level of the camshaft casing by about 2 or 3mm. This area corresponded with a flat on the inside of the valve cover meaning that the flat and the cam chain guide were touching each other and keeping the cover from sitting flush.

Of course, with the gasket in place and the cover bolts torqued down this would probably 'push' the chain guide back down but it didn't seem right that there should be pressure on the cover where I didn't need any pressure. So, the first thing I did was to remove the cam chain tensioner underneath the carbs to take tension off the cam chain and the guides. Then, I got a flat file out and filed the top little lobes of the nylon cam chain guide so that it was flush with the engine casing. Then I re-installed the new gasket and cover and finally, refitted the cam chain tensioner. The result is no leaks or weeps and I didn't use any gasket sealer whatsoever. Has anyone else noticed this?

Paul

[Stig]

Never heard of this issue. Has anyone had the engine apart previously that you know of?

[PaulM]

Hi Stig,

No; I've owned the bike since new and do everything on it myself - even the valve shims!