So I was break boosting my stock twins on the freeway in 3rd and as soon as a shift to 4th I see SMOKE everywhere behind me. When I pull over I see oil on the ground (turbo side)

Are my turbos really blown or is it just a rebuild on the seals?

 

When an apex seal fails, it doesn't nessecerally equal clouds of smoke. Apex seals differ from piston rings in the sense that they do not prevent oil from entering the combustion chamber.

Your symptoms sound exactly like a blown turbo oil seal, though.

 

yeah, thats what I was asking - blown turbo seal. How would it blow, as I only boost 5 lbs.

 

turbos spin at 100,000 RPMs and see temps in excess of 2000 degrees...

Just food for thought, I have a set of stock twins that wont boost past 2PSI with only 40k miles.

 

Last I checked my turbos had no shaft play, and seemed very healthy overall

 

The only way to boost 5 lb is to have a leak. In which case your turbos could be under even greater stress due to running at increased RPM.

Dave

 

Would the air pump hose count as a boost leak?

 

Oil on the ground? Doesn't sound like a turbo SEAL failure (usually lots of smoke out the exh, oil in intake system, but little oil leakage externally) to me. More like a turbo oil supply-line problem.

Dave

 

yeah like i said there was tons of smoke billowing out the exhaust pipe. Also started it up this morning, TONS of smoke some oil leakage again on the ground. Oil everywhere under the hood. Planning to pull the turbos today..

 

HMMMM.....

Might be a PCV problem...

Link: https://www.rx7club.com/showthread.p...ht=pcv+problem

Dave

 

lol that thread is more or less scaring me into thinking its the oil control rings which is what I first thought. But I kept thinking along the lines of the turbos because of the turbo side leakage, oil everywhere BOV intake box, turbo side of hood, and under the turbos.

Those symptoms made me think oil supply line, then of course the smoking.. smoking throws me off.. maybe its a combination of oil supply line and busted oil control ring... I hope not.

 

Now that I think about it there are many other ways to have less that 8lb of boost. It's just that a boost leak is the most common. Air pump has nothing to do with it.

Pull your intercooler inlet hose and if there is a puddle of oil down at the bottom, you probably have a turbo problem. If there isn't much oil there, start looking at other parts of the engine. PCV is a good idea.

 

Well, I think I found the problem as I pulled the downpipe out today. Secondary impeller unit almost fell out with it. Dp leaked a lot of oil and seems like my impellers spun themselves off... anyway, what about a ACV for a leak source? Could that have been the problem that led to my over boosting?