On cold starts (or several hours of sitting) when I crank my engine, there is a puff of grey smoke out of the exhaust. Not alot, but it's there. I can see it in the rear views. It only comes out when I crank, after a second, no more comes out. And if I park it and crank it again, there is no smoke. It is definantly grey, not black or white.

I was told this could have something to do with the valves or valve guides? I don't know much of engines (just enough to get by), and I hope that this is nothing major.

It personaly doen't kill me to see the smoke, but I'm going home this summer to my parents house, and there are 2 things that urks my dad about cars, when they leak oil, and when they smoke. I'd like to get this fixed before then.

Any ideas? Thanks!

 

usually that puff of smoke is just valve guide seals leaking

 

Ii've personally never seen a TPI that didn't smoke upon cold starts, my IROC did too pretty bad. I've always been told it was valve guides too, get your heads ported while you're getting them fixed.

 

so about how much is it to have a valve guide seal replaced?

hm... ported heads... but I'm a college guy pumping money into education and my cable connection If it's not to much more to get the heads ported (which I assume it is) then I'd love to!

 

Ditto on the valve guide seals, just get them replaced with steel-banded HI-PO seals.

 

I read somewhere that machining is sometimes needed when replacing valve guide seals... is this usualy true?

What price should I expect when looking around for a place to do this for me?

Thanks!

 

NO, machining is only required for the taller "teflon"seals. The high performance stock replacements are available at most auto parts and can be installed by any decent repair shop, without removing the heads using an air-compressor. All of the rockers are loosened up and removed, then the cylinder is filled with compressed air. Then they compress the valve-spring and remove the retainer locks and retainers. Then remove the valve springs, now they can replace the seals and reverse the process.

***This is a great time to swap valve-springs, even if you just get a cheap($42)set of "K-Motion's"(@Jegs). It will restore lost performance above 3000rpms!***
(It'll quiet some of the engine knock and stop valve float and increase cylinder pressure pumping up the torque and hp.)

 

Thanks for the tips!! My engine is a stock (as far as I know) 1996 (I believe) 350 TIP GM Crate engine, which springs do you recomend?

Are the K-Motion's you said good? or just cheap? I don't mind spending an extra $20 to get better springs.

Thanks alot, I am probably going to order them (and the seals you recomended) some time in the next few days!

 

The reason it does this is because the valve isn't sealing all the way. Thus oil leaks down the valve into the cylinder so when you start up the oil has been dripping into the combusion chamber all that time and it all gets burned up in the combustion process thats why you don't see it afterwards because oil is naturally consumned during the combustion process anyway. You can do valve seals with the heads on the car but it is easier to take it off. Also could be extreme carboned valve but in school they say valve guide seals. Wile the heads are off and the springs are off. Check for mushroomed valves, and scoured or out of round valve guides. Also with the pushrods off roll them across the bench to make sure they are safe. This can prevent any future problems.

 

As said in all the Posts it is a Valve Seal problem that is commom in all high milage SBC engines. This is not a problem, unless you are using a lot of oil. Just leave it alone take the BS and save the money.

 

If you can borrow a compressor then you can change your valve seals for like $30...it's a time consuming process but in my opinion it's worth it not to blow smoke every time you crank her up. However if you don't have the time/ability then it's probably not worth what a shop would charge...the labor fees would be a couple hundred at a minimum.

 

I surely don't want to try this on my own, nor do I have the time to, so I will take it to a shop sometime before summer time.
(ahh, cars cost to much money!)

I have a few months to wait, so I might as well save up a little extra and get new valves, push rods and rockers (roller rockers?). Anything else relativly 'minor' to get replaced while I'm at it?

 

If I were you I wouldn't change the valves. Everything else can be done with the heads on the engine, and if you get into pulling heads then you're talking about a big chunk of change. I'd just change the seals and replace the springs, and get 1.52 or 1.6 roller rockers if you wanna spend an extra $300. But before you drop that cash find out for sure what it's gonna cost to have the seals changed.

 

That sounds like a good plan TheGreatJ I'll do that, and leave the valves. 1.6 roller rockers would be "best"?

 

Yeah my IROC-Z sat for a 5 year period and i'm guessing that's why my car smokes everytime I start it up.

With 60,000 Miles on it also terrible..hehe