smoke at start up.

[paulfischer]

99 lumina LTZ with 3.8, 110,000 miles.
Heres the low down..... Changed oil yesterday, I ran a can of the gunk engine cleaner through it,(wanted to get rid of any build up/ sludge before switching to syn.) and I switched to synthetic oil.
Than today I get some smoke out of tail pipes at start up. than goes away.
Did the gunk engine cleaner get rid of too much build up?(if that makes any snese).
Or is there a bit of the gunk stuff that is burning off?
Does synthetic oil do that?
Never had any smoke before today. Or is it the valve seats/seals starting to go.........

Thanks for your help!!!

Paul

[jeffcoslacker]

That engine cleaner is basically kerosene. It made your oil very thin, allowing it to run past rings and valve guides when you ran it through.

Once cleared out, it should be fine. Otherwise, you washed out your valve seals with the stuff. Probably not, though.

I think it's probably fine.

[paulfischer]

I kinda thought it be the cleaner. (it wasnt doing this before I ran cleaner through) Ive never used the stuff before. But when I smell the exhaust, its smells like the clenaer plus a little oil.
How long does it take to burn off?? Its was a little bit better this am.
I drive about 80 miles a day, mostly freeway.
Whats your opinion on using the Gunk stuff?

[Jonn]

Originally Posted by paulfischer

I kinda thought it be the cleaner. (it wasnt doing this before I ran cleaner through) Ive never used the stuff before. But when I smell the exhaust, its smells like the clenaer plus a little oil.
How long does it take to burn off?? Its was a little bit better this am.
I drive about 80 miles a day, mostly freeway.
Whats your opinion on using the Gunk stuff?

Be careful on high miliage engines, so much gunk can loosen up it will clog the oil pump pickup, being that new you "probably" are ok, i have saw several engines that had a lot of years on them plug after a cleaner or kerosene was ran thru them.
And also... weather anyone believes this or not, in recient years, i have saw 2 ford truck water pumps, one dodge truck water pump, and a pump on a John Deere tractor all fail within a month or less after a "treatment", they all had one thing in common, cooling system cleaner was used.

[paulfischer]

i changed the oil very regularly, every 3000 miles. How much gunk can get build up????

Thanks!

[jeffcoslacker]

You are probably fine. I agree, in some situations it isn't a good idea. Lots of times people will try to clean an engine that has been neglected and is seriously hogged up with deposits, and they succeed in breaking them loose, and they all go into the pan all at once, possibly plugging the pickup like he said. On an engine that has been well maintained, that won't happen. But for that reason, the flush isn't necessary. The only time I have ever used it was as a last chance attempt to open up a severely clogged oiling system in a badly neglected engine that would need teardown to repair it anyway if the treatment didn't work. It's about 50/50 whether it cures it or makes it worse. All depends on how smoothly the deposits loosen and if they are solid enough to clog a pickup.

I just put kerosene in them when I do it. It will break it up better than anything else. But it is also hard on rubber and plastic, so I add it to the oil that's in there, run 5 minutes, drain it, refill and new filter (using cheapest oil I can get), drive a hundred miles or so all at once, then drain and refill with good oil and new filter. This is to make sure I've caught any kerosene that didn't drain the first time, and that the filter that caught the crud gets replaced before it clogs.

[paulfischer]

smoke is gone....... Kinda figured it was nothign major. but ya never know.

Thanks John and Jeff for you input.