Oil leak through so cylinder stud bolt

[bolhoso]

Hi all

I have a gs500 06 I disassembled the engine. When I reassembled again, I got a leak through the cylinder head stud bolts. I tried several things and the leak is still there: changed the cylinder head gaskets and O rings, changed the stud bolts gasket (the one made of copper),  retorqued the bolts, even tried applying Yamabond 4 to the bolts ND nothing stopped the leak.

I also checked the oil gallery that goes to the valves by blowing them and they don't look obstructed.

I really don't have a clue where to go now and I don't want to send the bike to the dealer,otherwise fixing may cost a lot and I won't learn or have fun.

I already searched a lot in Google, read the whole manual, even talked to an experienced mechanic and nothing...  Does anyone have an idea? 

I really appreciate the help!

Bubbles

[Big Rich]

I can think of 2 possibilities:

1) Is your engine breather tube clogged at all? Excessive internal pressure can cause all sorts of weird leaks.

2) Is there any kind of deformity on either the copper washer or the cylinder head where the washer sits?

[bolhoso]

The breather tube is a good question, are you referring to the one on the cylinder head cover? If so, I tried without it.
I can't remember of any deformity in the washers (they're new and looked pristine the first time I put), but I'm not 100% sure about the cylinder head. I'll probably have to look in another picture and compare.

Since I cracked the engine open, is there any chance the oil pump or some of the oil galleries down below got clogged and are increasing the oil pressure?

Is there any chance the camshaft is sealing that small oil passage? Maybe the camshaft journal?

I really appreciate any help, I' m kind of getting desperate!

[Big Rich]

There is a breather filter inside that cover on top of the engine. But if you remove the oil dipstick, you can blow into the breather tube and should hear air flowing thru the engine.

It's been a while since I was in any GS engine, so I can't really say much about the cam journals. Sorry.