Cattiva73

Yes its me again, you guys are so helpful that I only listen to your suggestions before I do anything...like a simple oil change .

...speaking of....:

-Im going to change oil/filter on my vette.
Which filter and oil brand should I use that is not synthetic?

-Also I noticed bluish smoke coming out the exhaust and I know it's probably the valve seals...my question is...is it an immediate fix? or can I drive like it is for a while?..will it hurt anything?

-Last question...I know Im such a girl but this Corvette is sure keeping me busy ...What is a "blowby"?

Thank you all in advance...I really appreciate it.

keithinspace

Wow. I'm sure you're going to get "Pandora's Box" type discussion on the oil and filter question.

Personally, I run WIX filters and Castrol GTX oil. In the past, I've run a particularly heavy oil (0W-50, I think) to keep my low RPM pressure up, but I'm currently rebuilding the engine and will probably be able to run a slightly thinner oil with the new pump.

I don't think there is much of a crisis in driving the car with leaking valve guide seals. Just that little bit of emarrasment, is all. But no lasting damage. Just be sure to put a full head rebuild (or new heads) on your list of "To Do" items. Think $600 to $800 for a rebuild or $1,000 to $1,200 for new heads.

"Blowby" is when combustion pressure seeps past the rings around the piston. It is evidenced by a variety of things, but in the end it results in lower cylinder pressures, higher crank case pressures, and could be accompanied by oil making its way into the cylinder during running. None of these are good things. But they aren't "catasrophic" either.

The real downside of blowby is that it means there is significant wear of the rings or cylinder walls. Perhaps even cracking of the rings themselves. By continuing to drive it, you could continue to score the cylinder walls to the point of not being able to recover the block. This will add to the cost of the eventual rebuild by your being forced to buy and recondition a core block rather than recondition your own.

MrJlr

Fram filter, Pennzoil oil

IF it's just valve guide seal (probably is)....not much to worry about.....very common on an old Chevy 350.
(My does it....)

MrJlr

racegofast

Smoke, how embarasing. lol. keithinspace good answer....

Mashman

When you see the blue smoke, is it only soon after a cold start? Or does it continue to smoke after the car has been running?

And what oil you should use would depend on what engine is in your car. Is it original? What year?

Cattiva73

It has a chevy 402 in it and the blue smoke is more at start and then its almost gone...??

Cattiva73

Im not embarrassed...its only smoke and its not much...I think it goes away after a while

keithinspace

Good point. For some reason, I read the post as blue smoke when starting. But in re-reading it, there isn't any mention.

General direction:

Puff of blue when starting = Valve Guide Seals

Little blue when driving = beginnings of valve seat issues or ring issues

Bug Fogger when driving = bad rings

If the smoke "goes away" as you mention, it would be a matter of degrees. Valve Guide smoke goes away pretty quickly, then the engine runs clear. Where if it is the makings of a ring issue, they could be 'loose' when cold, then get 'tighter' when hot. More smoke when cold, then LESS smoke, but still a small bit of smoke when hot. Dunno. Since you tossed the "blowby" word in there, it seems like we're heading in a 'ring' direction.

Again, none are "catastrophic". The car will still run. But the more severe the symptom, the more severe the problem. The more severe the problem, the more cost/effort involved in CORRECTING the problem.

oldalaskaman

loose the 402, asap

nomocrap

Ty a can of RESTORE for 8 cylinder it works great JAY

Cattiva73

I will. Thank you.

ezobens

Really? Are you serious or just pulling her (our) leg?
Does anyone actually use that stuff (or any other 'Engine Rebuild' in a can)? I've heard of folks of using sawdust too but honestly....

If all you have is a puff of blue smoke at start-up and it goes away, I won't bother with any snake-oil additives unless you're burning more than a quart in 1000 miles or so (and at that point, just get it fixed properly).
Just my 2 cents, your mileage may vary...

nomocrap

The stuff really works. Have an old tractor that smoked Restore cut the smoke down. Works till rebuild. Maybe some snake oil tricks might work you might try some JAY

briankeery

I think most of us with 30+ year old engines probably get a little puff on startup much like yourself. If you're relying on getting to work every day in this thing, then yes a rebuild may be very soon in your future. If however you're lucky to put 2-3000 miles per year on the car, then maybe this is something that can be left until absolutely necessary. Obviously your car didn't come originally with a 402ci engine, so no need to worry about originality. Save your spare change and budget a rebuild/crate replacement down the road. In the meantime enjoy driving your almost 40 year old automobile and some of the quirks that come with it.

Mashman

To add onto what keithinspace said, what happens when you have leaking valve seals, is that when the engine is cold, a little oil leaks into the cylinder(s). When you start up the engine, that oil will quickly be burned off, and you get a bit of blue smoke.

If that's you're only problem, then no it's not a big deal, it's a bit annoying, and embarrassing, but I would not worry about it. But just make sure to watch the oil level, and in the future if you have some work done on th engine, ask them about replacing the seals, what they are doing may make it a very simple job, and they might be able to do it cheaply.

Where did you hear the term blowby? Did you have a compression test, or some other test done? Or did you tell someone about the blue smoke, and they told you that you were suffering from blowby?

Do you know if you have a "flat tappet" cam, or a "roller" cam? If you have a 'flat tappet' cam, those are much older, and they rely on an additive they used to put in oils called ZDDP. They no longer put it in most oils because it is bad for catalytic converters. If you have a flat tappet cam there have been lots of arguments about what oil to use, and whether you need ZDDP or not, I personally use ZR1 Racing. If you have a roller cam, don't worry about ZDDP, I'd probably use Castrol GTX.

Make sure to check your oil at least once a week, and do it with a cold engine, and top off when necessary.

jb78L-82

A buddy of mine who built engines for years, owned his own hi performance parts store for another 10 years, and fixes volvos exclusively now-built more engines that most of us can dream about-swears by RESTORE. No Joke if you want to keep driving the car without a rebuild. Never used the stuff myself but apparently it works.

ezobens

To each his/her own but if my motor was burning oil so badly that I had to resort to 'Can-O-Rebuild', the motor would have been pulled and repaired/replaced long ago.
I can only wonder what else that stuff would be doing to the inside of my motor?

I'm also a bit skeptical of an engine builder that 'swears' by the stuff.
Seems to go against logic-
Kinda like a doctor that swears by voodoo medicine...

Just because he builds a bunch of motors doesn't necessarily make him good at it. Like doctors (or anything else for that matter), there are always a few good ones and a lot of bad ones. Over the years, I've run into many bad ones (of either profession) and rarely a really good one.
I'd also wonder about how many 'rebuilds' he's charged for and just threw some magic juice in the crankcase...

But seriously- It really is up to the individual.
Just not my cup of tea.
Elm

jb78L-82

I would not use it myself but you asked if anyone actually uses the stuff-Well apparently YES!!!

garygnu

you can replace valve seals with the heads on the car.air up the cylinder with the piston at the top of the bore.remove valve springs and the old seal.install new seal and reinstall the springs .do a compression check.maybe try a oil designed for high-mileage engines,it mite recondition the seals.