Leak down numbers
 

I have a 79sc with a 3.2 shortstroke motor rebuilt about 10,000 miles ago. After a1000 mile breakin it started to puff a little oil on startup. Over the next couple of years it has gotten to the point that on startup most of the time,it lets out a giant cloud of oil. While driving it never smokes,on the track ,autox or on the street. Leakdown numbers are all 1-2 percent.Checked with two differnt testers.
Plugs are coming out wet with oil .Pulled the headers and the ports are wet with oil. I tried going down along hill off the throttle then nailing it and no smoke.Can I be getting to much oil draining from the oil tank through the oil pump and flooding case while not running. Thanks in advance for info.
Stumped,Rbutts

My tank drains almost completely after a few days. I get some smoke on start up but not as bad as you describe. If your leakdown is really that good then your rings should be in good condition. I've thought about taking the oil out of the tank after a drive and putting it back in before the next start-up. That would be a pain but something to try and see if it helps. If you are not tracking the car you could try running with a lower level in the tank.


-Andy

If my car sits for a week or two (a frequent circumstance) all the oil drains into the sump. I crank it over for a minute or so to refill the tank somewhat. It's a tough start (carbs) in these instances so more cranking is involved. If the oil is all in the sump and you start it quickly with no oil in the tank......:eek:

Assuming that you have not inadvertently over filled the oil tank (which is VERY common), I'd be checking guide seals to see if they were damaged by a valve spring retainer or guide. I've this one happen quite a few times.

Then, I'd see if the screen on the oil pump PU is improperly installed allowing exess oil to collect in the case.

After that, its time to look at the oil rings since leakdown tests only confirm compression ring sealing.