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Will Mobil 1 Help Reduce "puff Of Smoke " At Start-up?



Like alot of small block chevys of the 80's, mine has questionable valve seals at 45,000 origional mi. It lets out a blue puff of smoke when started after sitting 1-3 hrs...overnight, its usually fine. I use Vavoline oil and a AC filter, change every 3000, with no measureable consumption between changes. I've heard that a good synthetic, like Mobil 1 , while clearly not repairing problem, seems to help MINIMIZE smokey start-ups. Has anyone else found this to be true...or is it something we live with short of replacing seals? Comments? I do not believe in STP, and the like, but if someone could suggest an alternative, I'm willing to at least listen. Thanks.
I have the same problem on mine but have never tried the synthetic trick you mention. Let's see what the others think. :upthumbs

_ken :w
Paul,my 96 has mobil 1 in it for 32000 miles and I havent seen a single puff. My brother has a 97 ramair furbird with 68000 miles its had mobil1 in it and his doesnt smoke either.
My '88 K1500 with a 350 did that when it was brand spankin' new. :eyerole

_ken :w
Ken , Our area manager has a new sts caddy and it does. The dealer told him it was condensation. {but its blue Stimpy}

my .02 is if the seals are worn or damaged with smoke on start up the use of synthetic oil will be as bad if not worse.the oil is very slick and gets into the smallest of areaswould run right by the worn seals that is why oil leaks sometimes get worse with synthetic oil.also why it is supposed to reduce engine wear gets to all engine parts faster on cold starts . won't hurt to try but don't be suprised if it seems to get worse synthetic gets every where . still great stuff in my book steve :w ;)
In the case of my truck, and also most of the 350s, until GM changed the type of seal they used on the exhaust valve, a lot of people had this complaint. :eyerole

_ken :w

there was an updated seal kit with positve grip seals and o-rings then another w/ differant seals for exhaust and intake some of the early 350 88 etc did not even have seals on the exhaust?????? steve:confused :s :crazy :w
You might want to try Valvoline Maxlife oil. My brother's car was smoking, so we tried the stuff and it worked. Of course, he overheated the car and busted the cylinder heads.
"What happened?" I asked.
"Ummm... it was getting hot, so I gunned it home. Duhhhhh."
:eyerole --Bullitt
What an eeeeediot

I think I lent my car to your brother one time. :) Actually I used to have a mechanic friend (worked for a GM dealer no less) to whom I lent a datsun I used to have. It had a small leak somewhere in the cooling system, but not broke enough for me to worry about...I just made sure it had water in it. I lent him the car and within a week he blew it up. He "forgot" about the water and when it started smoking he kept going because he was in a hurry and was late. :eek BTW--just to stay on topic for a second, I haven't noticed the telltale smoke from mine (with 71k on it) but then I haven't really looked for it. I'm using mobile1 also.
Have a 87 w/98k..
It is trained to know when to change the oil...
at 3000 miles I start getting the puff...
Change the oil, in a couple of days its gone..
Mobil 1 from day one...originial owner and myself.
So I just keep going....
Rislone? will Help Reduce "puff Of Smoke " At Start-up?

pauls said:
I do not believe in STP, and the like, but if someone could suggest an alternative, I'm willing to at least listen. Thanks. [/B]

My dad (RIP) would have suggested to you that "if ya don't put in a quart of Rislone yer car won't last more than 25 years!"
I'd replace the seals if it were my car. Sometimes the cost (the wife) can be prohibitive on that though. Hopefully, you will both "be on the same page" when it comes time to do the job.
Good Luck! (just a little levity...hope you find a solution to your concern)
Mooose (aka Scott):eyerole :booty

(I'm not being rude to paul...I've know this guy since we were 6 years old...so I thought I'd rattle his cage a bit)

Personally, I don't think it will help your smoke problem. In fact I would warn you that sythetics can cause more problems on an engine with high mileage that has been running organics. The reason that I say this is because I have first hand experience where the thinner synthetics were not compatible with paper based gaskets. They tend to penetrate these gaskets and make them soggy. When you go to WOT, the weakened gasket basically blows out.

I have had this happen twice on a Datsun 240Z that I used to track frequently. I lost two head gaskets on Mobil 1 (filled my oil pan with whip cream). If you do decide to go with a synthetic, make sure to tighten down every bolt to components that you can find that has oil running through it.

I run Neo sythetic Oils and fluids in my Viper, but it was broken in with a straight organic and tightened down. I don't care for Mobil 1, Royal Purple and Redline oils because they still recommend that you change them every 3,000 miles. I found that the reasons for this is because the organic cleaners and suspension additives do not last beyond 3,000 miles. Neo oils will last 12,000 miles with regular filter changes every 3,000 miles.

On a different subject, I also found that Redline differential fluids do not match up with Tremac T-56 trannies (for all of you C5 owners). The additives in it eat the synchros up and cause you to blow trannies. If the factory finds that you were using Redline, they will void your warranty.


Good luck.


Now that you have replies that go both ways, let me tell you what I think
Well, here comes MY two cents worth...
Synthetic oil, won't hurt, won't cure the problem
New valve seals, only real cure, shouldn't take more than an afternoon if you have access to an air compressor to pressurize each cylinder as you replace the seals, and if you have a home made tool or can borrow one to compress the valve springs to remove the keepers.
Second best but temporary option, a couple of the major oil companies are now selling oil specifically made for high mileage engines. I think Quaker State is one, not certain who else.
The blend has additives that help soften the oil seals, but it won't last forever.
BTW, there's still a lot of misconceptions floating around about synthetic oils, everything from cure all potions, to the reason why engines just blow. The biggest advantage to synthetic oils is their ability to continue providing good lubricating qualities at extremely high temperatures. I don't think they "eat-up' engine sealing materials, and their flow rate is based upon viscosity, just as is any petroleum or mineral based oil.
The valve stem replacement on the car job is not too bad. Vettepiolot is right on target. I have changed many sbc seals in the car on several vettes, camaros, etc. etc.

With the low miles on your car, your seals must have gotten dry and brittle from LACK of use. Had the same problem with my low mile 86 convertible.

I really don't care either way on the oil. Been running synthetic in the cars I really care about and even my little 3 cylinder GEO metro.
I had the same smoke problem, recently just before my next oil change was due I threw in a bottle of STP stop Smoke additive. I figured that I would be changing the oil in a few hundred miles so how much harm could it do. It worked! Smoke reduced considerably on start up. I been using it with each oil change for the last year or so. I doubt this is a permanant fix but it works for now until I can replace seals.
About the Synthetic oil. I was using Mobil 1, leaked out everywhere. I wouldn't use it again. I tried Quaker State Synthetic blend, much better, less leakage. Now I'm back to Castrol GTX 5-30. No more leakage.
My take

My 88 had mobil 1 in it however the guy had not had an oil change in over 7500 miles,what was on the stick wasn't pretty.

Now I've been a Casterol 20-50 GTX guy since
my 67 Mustang ( 1st car ) and have had no internal lubrication problems EVER.

I switched, I got a little seepage on the front seal..that's it and the car smokes just a bit on start up ( more from leaky injectors than oil I'll bet)

smoke at start up

dont change to mobil one , it can make things much worse. check your intake gaskets along with the valve seals. the intakes on tpi and LT1 will leak and let oil in to the heads and when you start, it will smoke. also make sure it is not leaking injectors, that will cause smoke when you start the eng. it will not be rich blue but more grayish

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