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mikeshoup

Oil Burn at Startup

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My turbowagon gives a puff of smoke out the tailpipe on cold startups. Its actually just started doing this the last couple days.

 

This is typically valve stem seals, right? As long as I top it off with oil, it should be fine? If that's the case, I'll just keep the oil topped off and drive it.

 

Could it be the ATF? I've heard the ATs can cause the engine to burn ATF, not sure when or how. But could this be it?

 

Could it be the turbo? Not sure when turbos can cause an engine to burn oil.

 

Kinda hoping its not valve stem seals, as I can change the rest easier. If its valve stem seals, that required removal of the heads, right? Can I do it myself, or is this something better left to a machine shop?

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Sounds like valve stem seals, yeah. You can replace them without removing the heads. You pressureize the cylinder with shop air to hold the valve closed, and then take the spring off and install the new seal.

 

GD

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Don't really have access to shop air...

 

What about, a rope in the cylinder? If I turned the engine to the compression stroke of each piston before I removed the valve seals, wouldn't the valve up?

 

How do I remove the valve stem seal?

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For a first-timer, it's better to use rope in the cylinder instead of shop air, there's less chance of bumping the valve open and having it drop into the cyl than with air.

Valve stem seals are the easiest and cheapest of your possible repairs. ATF burns whitish-grey and STINKS, so probably not that. The turbo seals are another possibility, especially if you don't let the car idle down for at least 30seconds before shutting down, if it gets lugged at low rpms for extended periods, or has been overheated at all. This is especially an issue on the earlier non-water cooled turbos, since their cooling came from the oil.

The most likely cause, though, is rings. These engines, with their horizontal configuration, don't always follow the conventional causes of oil consumption. Pull the spark plugs, and look into the cylinders. If you can see oil in there, then it's a ring problem. Also, if you are now parking on a sideways slope, try parking so the car sits level side-to-side, since there won't be as much gravity assisting the oil to get past the rings.

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mike your living up to your tag,

it shouldn't hurt things in the short run to drive it like that, but in the long run it would be a good idea to get your heads rebuilt

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Is it due for an oil change? if so change it and use a qt of Rislone, or some SeaFoam, MMO, etc in the oil. It could be as simple as a sticking ring. Mine would puff at every shift untill I changed the oil with rislone in it, now it doesn't puff....

 

If you use a rope, use one that isn't much smaller than the plug hole or it will knot up in the cylinder some how and you'll really get mad! Also soak the rope in motor oil first.

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Valve stem seals, easy to replace, you can live with it (depending upon how much your neighbors like you). Mine did that rather heavily at startup after sitting for 3 months. It doesnt take much oil to make a lot of smoke, so its not horrible, just ugly looking. Keep an eye on your oil level.

 

nipper

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DO NOT USE SEAFOAM IN THE CRANKCASE. This will fire you rings in less than5 mins of driving it. I know becuase a freind of mine with a b16 tryed it he only has 30k on engine and rings leak 40% now. Also if it is seals then when you floor it it will not smoke like bad rings will. Bad rings smoke bad at WOT. I would check turbo seals and valve seals. Does it only smoke on cold startups then when you let it warm up and turn it off the restart smoke again or not as bad? Seafoam works great in brake booster only use 1/3 can and change oil right after as it will leak past when you let it sit for 5 mins before the restart.

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Yeah, it just burns it on cold startups and not at WOT.

 

Strange thing, this morning it did not do it, though its been a warmer morning than the last couple days.

 

I changed the oil today, put a quart of MMO in it, ran it for 5 miles, and changed the oil again. We'll see if it does anymore.

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What weight of oil do you use? Did it do this in the summer?

I just bought the car, so dunno if it did it during the summer. It should also be known that this car sat for quite a long time being driven like maybe three times in the past year+.

 

I don't know what weight of oil was in it before, but I put in 10W-40.

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my hatch had similar symptoms a while back but it turned out to be the modulator on the auto trans. every time i started up there would be a cloud of bluish white smoke that was real thick and smelt vile. new modulator from subaru and it's been fine ever since.

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Since it sat for so long, it could just be a sticking ring, deposits burning off, or dried up valve seals. Next time leave the MMO in.

 

I have to say that I can't believe the SeaFoam hurt the rings in an engine. I have used it in the crankcase of at least 6 vehicles and have never had a problem. And I leave it in untill the next oil change, although it has been said that it will evaporate of after a while. I think that engine had other issues.

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