View Full Version : Burnt valve in Kawi head..valve job..or replace?

04-27-2008, 12:51 AM
I took my Kawi (FH641V) motor apart today to see what caused rod or piston to break. Obvious as cylinder was totally packed solid with mice nest. Plan on replacing rod and/or piston (or both) on bad side. But,..I see exhaust valve is burnt bad on that side. The seat appears ok. That side is much cleaner in bore too, maybe from the heat? But do I need to have valve job done on that head..or..both heads? or can I buy the valve-lap it then install in head..or does it need to be ground? bore looks super. Will know Monday if it was rod or piston..but it is broke loose from crank for sure. Because of heat on that side..any recomendations here? thanks- Geno

04-27-2008, 01:12 AM
It depends on how long you want this repair to last ?

You could just lap a new valve in if the seat looks good. But, A good repair would be to have all the seats and the three other valves ground then all lapped in and new rings installed in the good cylinder as well.

04-27-2008, 08:46 AM
I was planning on honing and re-ringing both cylinders. I wasn't sure on the valve..but think I'll send 'both' heads in for valve job. Any good recomendations on service on these? I'll check around here local (Madison,WI) but perfer to send out to where guys here have had 'good' work performed. Gene

04-27-2008, 10:39 AM

Most any auto machine shop and some mower shops can do this, I have the equipment to do it in-house so I don't have to send it out.


04-29-2008, 01:37 PM
I finally got to pulling bottom off block- It's a mess in there.. motor is shot. cylinder skirts on both sides are busted out big. Rod did a number on crank as well. I have a line on exact replacement of a used..RUNNING..Kawi motor except is 23hp instead of 21hp. $300. good price so debating on giving it a chance. I can't afford new right now. My other concern is this: What all should I save off this motor for spare parts? obviously starter, but what other parts are a good thing to save? room is getting to be a factor..so want to save only what is a good possibility I'd need down road and/or what is very expensive to buy new. (coils-carb-starter-good head, or both heads?-push rods&rockers- these are what I'm thinking) what say you?? thanks -Geno