gs 400 cam problem

[Guest]

Hi I'm currently putting my gs400 engine back together. Iv to put the cams back together and when the bolts are just finger tight the cam won't turn without force. The opposite cam (intake side) moves freely when torqued. The other is only finger tight. I think the head is damaged where the cam slots in. It's got a couple of slight dents and burrs. Is there and way to fix it ?

[tom203]

You got correct cam caps in right spot (the ABCD stuff ) and where did these "slight dents and burrs come from?

[costa]

I may have to take some photos but there was slight damage on the edge off the cam seat (not sure how to describe it better ) when I slipped replacing the exhaust valve. However it's the outer side that is catching. Best to describe looking from above there is the oil gallery in the center of the cam guide. The outer top of that is catching . I'm thinking maybe giving it a light sand with some fine paper but not 100% on what the tolerances are being an oil way.

Hope this makes sense.

[costa]

Right got this sorted. After much head scratching and swearing it turned out to be the simplest thing I had missed. One off the valve shims was too large. Which might explain why the valve was burnt out in the first place. Anyway I have put a smaller shim in and checked the clearance and my .0015 feeler won't fit in. I belive the tolerances is between .001 and .003 but what is the standard shim size? It currently has 2.65 shims all round.

[tom203]

Hooray! Get some smaller shims, like 2.60 and 2.55 for future fun. Join shim club - PM member ghostgs1.
there's no "standard shim size "

thanks for update- I like simple solutions!