timin questions....

[john buck]

ok i have a few questions but first let me explain... bought a 97 sho for 500 bucks off of a garage.... the motor had spun a cam... they replaced it... then the owner of the car had emergency family issues and said they cud have the car for the work they had done... i have all the reciepts and papers on the purchase of the new cam.. and the hours of labor and everything.... i started the car up and its pretty rough... it runs but has one heck of a miss to it... so my question is wud it jus be out of time?? or wud some of the valves be warped??? or head damage maybe??? ive read up a little on "life after spun cams" and im not to amazed by my findings lol... and suggestions anyone... all help is greatly appreciated.. thanks guys

john

 

[Mr Anonymous]

Spun cam = bent valves.

There are quite a few people lately bolting in a new cam thinking that solves the problem. Nope.

Time to pull the head and rebuild it with 8 new valves, and hope none of the pistons cracked.

 

[john buck]

thats wat i was afraid of... im curious to why you would only need to replace eight of the valves?... does this only bend the intake valves?.. but since you're replacing half of them would it not be obvious to replace the other eight? ... and also does anyone have an pics of the cams before and after they have spun.. or would it be obvious as to they way they look?



once again thanks.. john

 

[Mr Anonymous]

thats wat i was afraid of... im curious to why you would only need to replace eight of the valves?... does this only bend the intake valves?.. but since you're replacing half of them would it not be obvious to replace the other eight? ... and also does anyone have an pics of the cams before and after they have spun.. or would it be obvious as to they way they look?



once again thanks.. john

Rear head cam failures always bend the exhaust valves, front head failures always bend the intake valves. Regardless of which sprocket slips, it's always the slave cam that stops turning in time. The other valves are fine, so there is no reason to replace them. Just a cleaning and hand-lapping is all that should be done.

Spun sprockets are easy to identify, they're the ones that move. Usually a good amount of metal filings around the area too.

 

[john buck]

ok thanks man.... i really appreciate it... guess ill dig into it this weekend and see wat all is goin on in there lol... thanks again.]

 

[v3r71g0]

Yea you can get some 600-2000 grit sandpaper and hand lap the shims on a glass table or really flat surface.