Brandon50394

My chevy 350 in my vette dropped the valve spring and the valve hit the piston and dinged it up a little is it safe to run the car?

TimAT

Not me. THe valve is probably bent. Pull the head and take a good look and the valve, piston, cylinder wall, and the head.

Brandon50394

I did pull the head the valve bent the only thing that was hit was the piston and it's just dinged up a little but everything else is good

'75

Can you post a picture of the piston?

http://forums.corvetteforum.com/c3-p...tep-guide.html

Brandon50394

Brandon50394

its not cracked or anything

Marlin

You means its not cracked on top. I have seen damage like this look ok but be cracked in the ring groove or under the piston.

Its your call. Could be fine could be other issues.

MotorHead

Get an air hose and blow the crap out of the cylinders, button it up and cross your fingers

'75

I'd run it in mine.

Ben Lurkin

As long as there's no cracks, fix the bent valve, button it up and go.

drwet

I'd run that unless it was a numbers matching engine that I really valued highly.

TimAT

Kind of like Roulette.. You spins the wheel, you takes your chances

But hey, I've gotten away with stuff that everyone said would either never work or last all of 10 minutes too.

junkman123

just be sure to sand the dinged up place to smooth it out the eliminate any hot spots so there will be no detination

Indiancreek

It's not hit as badly as I've seen on others. I agree with the sharp edges dressing. I think I'd try it unless I felt like pulling the engine. Had the heads been worked on in the not to distant past?

bashcraft

I had a mid 70's Cadillac that did the same thing, but the piston looked much worse. I replaced the valve and ran it for another 50k miles before I traded it in.

wcsinx

At least get it nice and smooth first.

wnmech

Like others have said you are probably ok but if it were me I would take the extra hour to pull the oil pan and disconnect the connecting rod and push out the piston just to be sure. You are that far torn down and it's so easy to drop the pan on these cars why not be sure and do the job right the first time?

joewill

is not that easy, the cylinder probably has a ridge that will need to be reamed in order to get the piston out,
you might break rings and drop them,
might push some shavings into the crankcase,
might have to hone the cylinder,
you might have some cracks that you cant see with the eyeball,

so to do it really correctly purchase the appropriate one piston and one ring set. purchase the ridge reamer, purchase the hone, purchase the proper mikes and calipers, etc..

oh, to do it really correctly, take all the pistons out and balance them with your new one...

point is, just button it up and try it, see if it is ok.. else rebuild the entire thing.

if one valve dropped, you can bet another one is set to go soon, so at least send your heads in to get them done..

427Hotrod

Is that a forged piston? How beat up is the head? Pull it to the top and measure the deck height against the other pistons. You can bend a rod also when a valve drops if it smacked it pretty hard. Did it die or keep running when it dropped?

JIM