This has been an long on-going problem that has worked its way through many threads over the last two years.

I have an S5 T2 that was recently rebuilt. The engine probably has no more than 7 hours of running time on it. The housings were street ported by Rotary Evolution.
For the last couple of months I was chasing the idea that the turbo was smoking. I bought a used turbo on here and when that one smoked, I bought another one on eBay. The reason I thought it was the turbo smoking was because I took the turbo out of the intake stream and the engine didn't smoke any longer. But, evidently, I just didn't let it run long enough.

Anyway, I'm pretty sure now that the smoke is coming from the engine. I suppose the most likely culprit would be the oil control rings. But, the rings were new after market Atkins Rotary Viton rings and the springs were also new.
If the rings should be OK, where would be the next most likely to look?

 

try pressure testing the cooling system and see how the engine starts up after pressure testing it.

i learned the hard way about these engines and electrolysis, a housing may look ok but tiny drill holes can be in hard to see spots, some in the exhaust passages may not even give indication of pushing coolant through the engine and run perfect aside from smoke clouds out the exhaust.

i know the porting is fine on the outer plates, what did the center plate look like inside the oil control seal area?

it may be difficult but trying to figure out what it is burning is the next step, a cooling system pressure test should give a hint if it is coolant or not.

 

The exhaust smoke doesn't really smell like antifreeze but I have to start someplace so I'll do the pressure test.

thanks ben......... my dad says thanks too

 

I can't help but wonder if an oil control ring got pinched or had its spring installed backwards.


When you took off the turbocharger were both exhaust ports equally dark in color?

 

I didn't notice. Should they be? I just started the engine and checked to see if it was smoking, which it wasn't, at least not yet. Maybe I can pull the turbo again.
If it was a oil control ring shouldn't it smoke right away?

 

I pressure tested the cooling system. I pumped it up to 15 psi and let it set for about 15 minutes, it dropped about 1-2 psi. The pressure testing didn't seem to have an effect on how the engine ran.

The smoke doesn't really smell like oil or antifreeze but it smokes more now than it did last week. It can completely fill a 3 car garage in a few minutes.

 

how long have you run this engine for?

sometime oil/coolant will collect in the exhaust and take upwards of an hour or 2 to dissipate/burn off.

 

I'm not exactly sure now. I'll take it for a ride out through the country and see if the smoke starts to clear any. Definitely can't take it through town because a cloud follows it.

I think we are quickly running out of options. We should have bought one of those JDM engines from Japan2LA.

 

what happened with the tests on the turbo thread? i didn't check back to see if there was oil in the housing before the turbo. if there is oil coming from the engine then it will show by running the engine with the turbo off the car and lines blocked.

i also pitch any oil control rings that have nicks are scars in the shiney contact surface where the seals touch the irons, did you inspect the oil control rings thoroughly? did not sandblast them or run them over a wire wheel? they should be cleaned in a tank of carb cleaner or scrubbed by hand. recieved one engine that they bead blasted everything.. iron surfaces, oil seals, rotors, housings, etc. that engine consumed about 1 quart every 50 miles(made to nearly 500 miles before it got to the point that the engine was siezing up because the bearings were grabbing the e-shaft because there was still media in the rotors and oil system), it was horrible. strangely it didn't smoke a ton, but it was also a non turbo. that said there's only a few parts that can be media blasted and i'm just throwing out ideas to try and figure out what the problem is.

 

No, I didn't sand on the oil control ring holders. We used a tank of carb cleaner and let them soak and brush them with a parts brush but we could have missed something. I should just have my friends take the engine back out, disassemble it and take a look. What should I be looking for? Oil or water?

 

i would be sure it isn't the turbo before ripping the engine back apart. can you block off the lines and run it without the turbo?

 

Today I did find oil puddled in the bottom of the turbo manifold. There wasn't a lot but probably a tablespoon full.
Is it possible for oil to get into the manifold from the turbo? Or, is this the clue that we have been searching for, pointing to the engine?

 

if it's before the turbine wheel in the exhaust towards the exhaust runners from the engine then it is coming from the engine. try to see which exhaust sleeve is wet with oil if not both. that can help you isolate where to look for the issue when you tear the engine back apart.

 

The oil is coming from the front rotor. The rear exhaust sleeve is dry.

I'm not sure why the oil didn't show up in one of the other times that the turbo had been removed. If it wasn't a holiday weekend I could gather a couple of friends and pull the engine but I'm sure everybody has already made plans.

 

To tell if its turbo or engine itself helps pulling spark plugs....

In most cases, bad side seals or oil control o-rings will show up on spark plugs....

 

OK, I'll pull the plugs before I disassemble anything else. I don't see any sense rushing to pull the engine. Project Angie has now reached the two year mark.

 

I pulled the plugs. All were black and some had oil on the inside of the seal but I'm not sure the oil is visible in the pics.

front rotor and then rear rotor

 

Sorry if this has been brought up already. I have seen some major smoking from engines that have all the crank vents capped.

Just an fyi.

 

Thanks for the input but it will still smoke even with the oil fill cap off. I have the charcoal canister connected to the bottom port off of the oil fill spout and then its routed back to the fuel tank, if I recall correctly.

 

clean them up real good (to the 'new condition'), put them back in, crank it over and pull them again.....that should tell more.....

 

I re-installed the plugs, cranked it over twice for about 30 seconds each time. The front plugs have a coating of oil, not dripping wet but if I touch them I can feel the oil. The rear rotor is mostly dry. I can't feel the oil but when I touched the plugs to a piece of white paper they both left a ring.

 

I am not sure if my tip helped, you might need to elaborate more, but this is way how i diagnosed bad side seal and when i teared engine up, it was what i expected it to be....

 

Well, its time to pull the engine. Its time to take a look inside. Hopefully, the problem will be easy to find.
This will the third time that this engine has been removed from the car.

 

I drained the engine oil and the oil was really dirty. Dirty like 3000 miles dirty, but the engine only has about 7 hours on it.
What would make the oil that dirty with those few miles? Of course, everything was spotless for the rebuild.

 

Well, the engine is out of the 7. Step 1 is complete. As my grandmother used to say "Many hands make light work." I had two guy friends help me. They both have helped before and one has his own 7. Maybe tomorrow I can start dismantling it.