Anyone had piston ring issues after cam swap? any causes for bad rings?

 

Damn if I know bro., but maybe you can tell me do you have to pull the crank to change rings?? Its just that I thought I read someware that you could change them just pulling the heads? I know I know I dont see how It would be possible either, but........

 

Its not likely. What are your symptoms? Chances are you didnt install new valve seals with your springs or you didnt push the new ones on correctly until you feel them snap into place.

 

What is the symptom you are having? If smoking what color is the smoke?

 

the smoke is light blue/white, i have changed the seals. twice now in fact, the first time i was unaware that they snapped down so i had a big oil leak, i replaced them and i thought i snapped them down but the car has never stopped smoking since the cam. the car has 30000 actual miles on it and maybe 3500 on the cam, so I didnt think the rings would be bad but im rackin my brain here. by the way its the f15 if it makes a difference

 

Compression and leakdown test would be my next step.

 

You don't pull the crank to change rings.

Pull the engine out of the vehicle, remove the heads, remove the oil pan, remove the pistons and connecting rods together out the top. No reason to remove crank.

 

Thank you heapashifter

 

sucks....

 

If the car has only been smoking since the cam install, the rings are probably fine. It is possible that during the swap, you may gotten some oil down in the cylinders, and it's just taking it awhile for all of it to burn. The other side would be if some debris happened to find its way into the cylinder walls, it could have scratched up the walls or a ring.

Both of these are far fetched but possible since the car is only smoking since the cam swap.

Jason

 

well i guess what im gonna end up doing is replacing the valve seals one more time, anyone have a preference on brand, and any special techniques to make sure they seat down nicely...
as usual thanks for all the help guys.

 

if it helps you at all I have some startup smoking. 49k on the car and it NEVER used a drop of oil.. 0w30 gc. Just completed h/c swap - could it now be the PCV? **** in the combustion chamber? The fact that the intake/exhaust valves are open at the same time for a split second causing a cough? No idea. There seems to be a lot of this going around after h/c swaps.

FWIW I had all the work done by East Side Performance so I'm assuming their work is top notch. I'll bring it in the shop tomorrow to have em' check it out and post up their response.

 

Can valve seals be changed with the heads still installed on the car (like at the time of a spring/cam change)?

 

Yeah. After you remove the spring, you just grab the seal with pliers and pull it off, and install the new ones.

Tony, I never felt my valve seals 'click' on. Ls1howto says to just tap them on, and they might not touch the spring seat at all (00 car). I didn't feel really good about doing the seals because there didn't seem to be a definitive stopping point for each, the gap seemed different for each one. I guess I did it right though because it doesn't smoke any, so I dunno.

 

Yes, they can......get the Felpro seals. They're viton rubber, best you can get.

 

^ Yes.

 

I always use stock GM valve seals, sometimes all brown, and sometimes brown/black. If you push the seals on by hand without tapping, you will feel some resistance on the last 1/8 inch or so before you finally push hard enough to overcome this and send them home. When if finally seats, you can clearly feel it. Make sure you use a deep socket (12mm or 13mm, or half inch if you actually opened your SAE stuff while working on the car). You also dont want to push against the palm of your hand otherwise youll have a bad bruise by the end. Pad your palm with a shop towel or piece of carboard or something if you can.

If you tap them on, you kind of have to listen to the sound when they hit home. Itll be more of a thud. Its not terribly difficult to tap them on, and on many heads the actual valveguide can vary in height. If youve seen a head minus the valves, the guides on the bowl side are sometimes pushed in different lengths. I dont think it varies more than .050 or so. If the seals were tapped on enough, they probably wont come off even if they wern't seated all the way on. However Ive had a few friends tap them on only to pull the valvecovers and see the seals riding the top of the valves. Usually oil consumption is what tips them off.

The 01+ cars came with integrated valve seals / seats so they touch the bottom, but if you run aftermarket springs, you need to use the old style seals, which of course will not touch the seat.

Hope that clears things up.

And Kelly, Id pull your valvecover and take a quick look next time you find yourself in the area. I mean, it dosnt take but a few minutes to pull the valvecovers Besides, you do more wrenching that I do!

 

Dont forget to use the TDC method lest you drop a valve and have to try and push it back up!

 

Do a leakdown and if the results are bad, listen for air coming out of the oil fill cap, that will tell you if the rings are bad