oily spark plugs

[5thAve]

So my '91 VFR was running like crap at the end of last season. I parked it and put it out of my mind over the winter. Now it's back in my garage and it's time to face up to my (mechanical) demons. So I spent an afternoon removing the spark plugs (yes, a whole afternoon. This is why I love the GS so much. No fuss when it comes time to do work on it).

All four spark plugs are slightly fouled with "wet carbon" which is actually dry, but is a fluffy black deposit on the outer rim.  Also, the threads of all four plugs are wet with oil.  I'm pretty sure that the oil did not get onto the threads as I am removing the plugs. There is no sign of an external oil leak. So basically this must mean oil in the combustion chamber, which can only come from (a) blow-by past the rings=worn rings and cylinder, or (b) leaky valve seals/guides.

So I'm pretty confident I know what is going on, but my question to you good folks is this:  How reasonable is it that this leaking is happening in ALL FOUR CYLINDERS AT THE SAME TIME?  I mean, maybe it's just the age of the machine (1991) and all the valve seals have given up the ghost...  or maybe I'm missing something here. 

Looks like I have to get my GS reassembled  so I can take the VFR off the road for a while. 

[Big Rich]

Did you do a compression test?

[mister]

"running like crap" is a pretty broad term.

As for the sparkplug thread, can you be 100% certain a layer of oil was not put on them Prior to insertion?

Maybe a photo would help?

Does this chart help?



Michael