White smoke coming from engine?

Hi, I'm a very experienced mechanic, I just want some second thoughts on this. One of my project cars is a 79' cvcc honda accord. I just got the engine to turnover today, but there's… A looot of white smoke. But it usually dissappears after a while, unless you rev the engine, and the engine is also very noisy when idle, or in nuetral, but when shifted into first, it all goes away, (yes it is coming from the engine.) The smoke is a very white colour, I wouldnt say very blue… It has been cranked on ether before I know, the guy I bought it from did that, a lot. What do you guys think? I'm thinking there's too much gunk under the valve cover and the oil is fallin into the combustion chamber… The oil is a good bit darker, like a half yellow half brownish gray translucent colour. I'm just hoping I don't have to rebuild down to the head gasket.

Well, fer sure something is leaking into the cylinders. Oil? Coolant?

with a '79 and who knows how many actual miles, oil leaking past the valve guides and valves and thus into the cylinder is a fairly good bet.

did you test the compression? Might want to do that… And if its more than just a bit low you may be looking at a ring job, too. [If you do a ring job, might as well have the valves ground as well -- you'll have it all torn down anyway.]

I've only ever done two ring and valve jobs. Admit that I can't recall what the oil looked like when we decided they had to be done. That "… Half brownish gray translucent colour" doesn't sound too good, tho… Almost as if coolant is leaking a bit and ending up in the oil pan. And yes, that would suggest head gasket.

If the compression is good then the supposition of head gasket is, i'm afraid, higher. And oil leaking past the valve guides could still be happening -- esp if the car was driven or sat in a brutal climate [you didn't say where… Central Australia?] that dried out the wiper pads inside the valve guides.

White smoke usually indicates water or coolant turning into steam. Seeing as the car apparently has been sitting for a long time without running, it could be that there's condensation in the exhaust system and and fuel that is turning into steam. The fact that the oil is not the color of a melted chocolate milkshake is good, but it having the yellow/ brown tint could indicate coolant in the crankcase.

Gunk under the valve cover would not cause the smoke issue. Bad valve seals allowing oil into the combustion chamber would cause smoke, but it usually would be more blue than white.

I would try running the engine to see if you lose coolant or have overheating problems. If you think the oil is gunked up, try adding a pint of Automatic transmission fluid to the engine, run it for 20 minutes or so, and then change the oil and filter. The ATF is high detergent and it will clean much of the gunk out.

One thing that is not clear to me is whether the smoke is coming from the exhaust or up under the hood. If you are talking about under the hood, I don't know if your 1979 engine is like Honda's more recent 4 bangers, with the oil pressure sender straight above the exhaust pipe. If that sender leaks it can fill a garage with white smoke in a few minutes.

If it is coming from the exhaust I would make sure it is not oil being sucked in the breather or PCV valve - the breather can be disconnected and left open for test, while the PCV valve can be blocked off both ways.

Either way I think you are describing oil smoke. BTW - that is no cat converter, right?