valve stem seals - what else

[traffico]

Replaced the turbo to discover that my great cloud of burning oil had ALSO been contributed to largely by failed valve stem seals.

The driving condition that produces the most smoke is when i get on the throttle after a period of high vacuum, or when driving at light throttle/high vacuum e.g. 4th gear down hill at 45mph a steady cloud of smoke...

After changing the turbo and washing out the intercooler with gas, whereupon the car had sat for four days or so, longer than usual, I primed the turbo with the coilpacks and injectors unplugged, and when i start the car, immediately a massive thick cloud of smoke! Which dissipated to a normal puffing of smoke after 20 seconds... This meant to me that REGARDLESS of the puddles of oil I had seen previously to pcv refresh and turbo replacement, regardless of whether my turbo could have been leaking oil from either side, that there was lots of oil getting into the combustion chamber, the only part of the car that could burn oil at a cold start. Substantial oil burning immediately at cold start means oil in combustion chamber right? Seems plain as day that my valve stem seals are totally shot to the point where they are leaking even due to gravity while car is sitting...


SO! I'll be replacing valve stem seals over the next few days. What else should I replace? Got new valve cover gasket, cam seals... Should I be doing keepers too? Are keepers and retainers the same thing? Any odd little clips etc. that need to be purchased? Thanks.

[traffico]

Cam chain tensioner as well?

[Furly]

Valve guides. If you plan on taking the head off. But unless you have the know how or tools to do the job it leave it to a reputable engine machine shop.

[redline380]

I second guides. It will be expensive though. It is possible to do this job at home if you have an oven but I highly recommend a shop do it or they won't be straight.

Of the 3 or 4 heads I've taken apart, all of had sloppy guides.

With that said, you wont get a bunch of oil in the combustion chamber if the seals are shot just by having the car sit. The oil is all the way down in the pan and can only make its way up when it is running. The seals are pretty well hidden and the engine usually needs to be running for the seals to leak enough oil past to get it to smoke.

Before you take anything apart, I would inspect plugs to see which hole is burning oil. One question for you though, did the oil smoke go away after running it? It is totally normal for everything to smoke a bunch on startup after a tear down. I usually drive it for an hour or so to burn everything off. If there is still smoke after that, you probably have an issue.

As for what the parts are and what they do, this is the best diagram I can find. The retainer "retains" the spring, and the keeper (lock) "keeps"the retainer on top of the spring. The lifter is the medium between the cam lobe and valve which allows the cam to ride on the valve without the valve/lobe wearing.

[traffico]

The seals are pretty well hidden and the engine usually needs to be running for the seals to leak enough oil past to get it to smoke.

Before you take anything apart, I would inspect plugs to see which hole is burning oil. One question for you though, did the oil smoke go away after running it? It is totally normal for everything to smoke a bunch on startup after a tear down. I usually drive it for an hour or so to burn everything off.

Thanks for the info/advice... I just don't understand how all that oil in the combustion chamber would have come from anywhere else. My intake tract was relatively clean this time around and I don't see how replacing the turbo would have leaked all this oil into the engine... Note: it smoked on startup after turbo change much more than it had previously, the only thing I could attribute this to was that it had sat for longer than before, or that it had been cranked without injectors or spark? And the massive cloud did diminish but I just assumed that driving it at that point I would experience the same ghastly smoking conditions as before...

As to guides, it's a great idea but I wasn't gonna take the head off to do the seals. If I'm pulling the head I might as well get an aeb... And this you can't do without an oven and without taking the head off? Very bad idea to use heat gun locally to r&r guides?

[traffico]

Background on where I'm at now: Burning alot of oil. Replace PCV components. Found large pool of oil in intercooler. washed out intercooler with gas, reinstalled, drove for a while, continued burning lots of oil. remove intercooler again found no oil in intercooler. looked at turbo found lots of shaft play. replace turbocharger. Start car, huuge cloud of oil smoke that diminished to a steady stream of oil smoke. Though you are right I will run/drive the car for a little while to confirm oil burning condition before getting into the head. And thanks again