Curing a different weep - O rings in head

As previously noted, the left side head on my '09 GRiSO has always weeped, causing a drip down the fins and onto my boot.

Spark plug boot looks like this:

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Right side is clean:

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O rings were changed once, under warranty, several years ago.  I plan to change them again.

Anyone been there and done that?

DW in NYC

As Dave up at Moto International is fond of saying...

"It looks like your right side boot oiler is failing."

In all seriousness, just get some new o-rings and thoroughly clean/examine the trough for the o-ring in the valve cover as well as the exterior of the plug tube on the head. Hopefully you're just victim of a cracked o-ring or a bit of debris fouling the seal.

The A8 motor went to a different sealing mechanism that has much more surface area to make the seal.

My theory is that the bottom O ring is the culprit. The plug boot is only oily on the bottom.

There is no secret sauce to get those rubber rings to seal?

The bottom o-rings are a bit more of a pain because, if your tube remains in the head, rather than in the cover, it can be a bit of a pain to extract. You have to be careful not to damage it as you pull it out.

Once out you can flick out the o-ring with a seal pick. Then give the area a blow out with compressed air and a tub with aerosol carby cleaner or the like before taking the plug out. Clean it first so you don't blow or wash crap into the cylinder through the plug 'ole.

I then lightly grease the new o-ring with rubber grease and install it in the groove, this can be very fiddly, be prepared to walk away and come back in five minutes! It will go in eventually. Wipe off excess grease and I give the bottom of the tube a dress-up with very fine wet and dry to de-burr it and get off any mank like baked on oil.

You can then, if you wish, (I only do this if I think the surface of the tube has been compromised.) put a very thin smear of Threebond 1211/Hondabond/Yamabond around the bottom of the tube before slipping it back into the head/o-ring. Replace the top one while you're at it but don't use Threebond, reinstall the cover, then the plug and cap. Cross fingers. Go for a ride.

Pete

Awesome Pete, I will report back tomorrow after a trip to the auto parts store for the prescribed emollients.

DW