Oversized Valves needed for Mercruiser 140 3.0L

[Doug L.]

Hi everyone,

I am searching for a source for oversized valves for my 1985 Mercruiser 140. Mine has worn out guides (~.008" side clearance) and is pulling in oil to the combustion chamber. They seem to be hard as heck to find. Might have to make my own guides and ream them. What have y'all done for servicing your guides? Any advice is greatly appreciated.

Thanks,
Douglas

 

[Scott06]

I thought normal installing bronze guides is done to restore the original valve to guide clearance vs oversize valve stem

not the best video but gives you the idea

 

[Scott Danforth]

^+1, what he said.

bronze guides are extremely common repair

take cylinder head to real engine building machine shop. day later, pick up cylinder head and install.

however the cost of doing that is about same as getting new head which is more than buying a newer used motor

 

[Doug L.]

I appreciate the replies y'all. I'll be taking my head to an actual machine shop to look into the bronze guides.

Thanks,
Douglas