78SC - smokes through warmup

[DSH1]

I've searched the posts - to no avail. Apologies if this has been covered before and I missed it.

78SC with 28K miles. Head studs snapped and that was the beginning of an engine drop, upgrades (tensioners / pop-off etc...) and the removal of the cat / smog in favor of SSIs.

All is back together now and it starts, warms up, and runs perfectly - except for the smoke part.

From a cold start, there is not a hint of smoke and it idles for a couple of minutes at 2Krpm. As it warms and the rpms drop, oil smoke (definitely oil smoke) starts to appear. Thick smoke. When it settles at just above 1Krpm, the smoke stops and it idles perfectly.

When driven, there is no smoke during acceleration and no smoke at decel - even hard, high rpm deceleration.

But when the car comes to a stop, there is always a brief cloud of smoke that blows past. Usually doesn't persist - till the next stop.

Valves were done when the engine went back together. I don't remember the guide condition, though I doubt they're worn on an engine this age. Oil is not overfull. Probably running rich by the smell of things, but I'm still getting used to the no-cat deal and I'm not sure what the new standard of exhaust smell should be.

I don't know if anything in the CIS / warmup / AAR circuit is oil-related. My CIS knowledge is a bit thin.

Otherwise, I'm stumped

[topcarbon]

did you overfill the oil?

[Joe Bob]

Ya need a LONG 3mm allen wrench and an exhaust gas analyzer.

What weight oil are you running?

[brads911sc]

Did you change the guides?

[DSH1]

I left the guides alone when i had it apart - didn't scrutinize them much, but the engine is fairly young.

Oil level is correct. Can't remember the weight but I might swap it as a beginning.

What baffles me is why the burning oil cycle during warmup instead of the start.

[pete3799]

Any external oil leaks?
Sounds like oil on the exhaust that won't smoke until it reaches temp.
Is it come out the exh. pipe?

[DSH1]

It's coming from the pipe.

I'm starting to think I want the cat back.

[FIG]

I'm having the same with my '78... Smoke (out of exhaust) during warm up after the car has been standing for a day or two. I do have an oil leak (or two )... Solution???

[T77911S]

check the timing advance, control presures then check the mixture

[FIG]

Cheers :-)