Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Help me out? white smoke out of the exhaust right when i start it up

I’m learning as i go so take it easy on me. =) First question i got is… I have the haynes book for this and all related models and engines 85 chevy is what I’ve got. I want to know what engine I’m dealing with for sure. Definitely a v8 but going by the book i still couldn’t find the engine code #. Think it’s a 305. Far as the smoke goes hoping valve rings? So much more wrong though buying parts as i can. Oil sender is leaking, rear main (or maybe that’s all just dripping from sender?) Cam shaft must have a worn lobe? because I tightened the rockers about 3 weeks ago and they’re loose again… It is missing changed spark plugs (helped but) probably should change distributor cables as well. And more but mind went blank and comp freezin up

White smoke is normal, unless there is lots of it. It usuall means the car isn’t getting enough gas, and black smoke means its too rich. Also white smoke could mean you are burning oil.

What you should do is stop right now and not spend another dime. It sounds like the engine is junk to me based on the worn lobe, rattling lifters, missing, smoke, and the possibility of a low oil pressure. A leaking rear main seal can also be a sign of a tired old engine.

I would suggest that you run a compression test and connect a vacuum gauge to the engine. This should tell you pretty quickly whether it’s time to look for another motor.

The figures will vary based on a number of factors but with manifold vacuum you should have about 17-20" of rock steady vacuum at idle. Compression readings should be in the 175ish PSI range.

I don’t agree. you shouldn’t junk the motor yet. If I were you, Perform the compression test. If you have good compression, simply replace the cam and lifters. They come in a kit at autozone for like a 100 bucks. Then drop your oil pan, replace your oil sending unit, and your rear main seal, and put the pan back on with a new gasket and plenty of RTV silicone. Oh and since your replacing the cam, may as well replace the timing chain and gears as well since you remove them to take out the cam. They cost like 20 bucks at autozone for new ones.

Loose rockers doesn’t necessarily mean a failed camshaft or even failed lifters. It could mean that the lock nuts aren’t locking any more and are simply vibrating loose.

The first thing you need to do is find somebody to help you, because based on your opening statement you’re already in over your head. At a minimum you need to read your manual again until you understand what you’re doing in better detail.

By the way, white smoke doesn’t mean not enough gas, it means it’s burning coolant, usually because if a failed head gasket.

Rattling lifters can also be a sign of very low oil pressure. (see worn bearings below)

A leaking rear main seal can also be caused by main bearings that are worn out or a badly grooved crank journal. The latter could possibly be fixed with a Speedy Sleeve. The former goes back to a worn out engine.

So I’m just guessing here but a compression test would eliminate any idea of a problem with cylinders? pistons? Just curious I learn things better if I understand why. Definitely gonna do the compression test b4 i go any farther thank you everyone. Did anyone have any ideas on where i could find my engine code number? The book says all v8 other than mark IV it will be located on a pad on the front edge of the block under the right cylinder.