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Old 02-08-2010, 10:00 AM   #1
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Default Big turbo problem - help please!

Ok, so I have a Begi Shanghai kit, FMIC, double piston BOV, 550cc injectors and an adaptronic using MAP sensor (so no need to re-circ the air - bov vents to atmos) and an oil cooler coming from a sandwich plate at the filter. There are lots of others but these are the features i think are relevant to this problem!

The car has only run turbo'd for c.800 miles and there is a massive oil problem somewhere as it is smoking like crazy. There is evidence of oil seeping up between the turbo/exhaust manifold union and the turbo/downpipe union. To me, this signals an inordinate amount of oil in the turbine side of the turbo resulting in lots of exhaust smoke and even some smoke in the cabin!

Where is this oil coming from?!

My first instinct is that the turbo seals have gone and oil from the feed line is going directly into the turbo...

The PCV valve has been checked to 30 psi and holds pressure so I find it hard to believe the oil could be sucked through the breather pipe on the cam cover, spun round the compressor, through the engine and then out in a high enough quantity to cause the seepage that I am seeing. Thoughts?

Turbo was only running 11psi by the way.

Anything you feel i've missed out of the story please let me know and I'll do my best to fill in the blanks. By the way, all cylinders have been compression tested and are in the range of 200-210psi. Because of this result no leak down test has yet been done - I don't logically see the point of one if compressions are fine - am I wrong?

All help and advice greatly appreciated by a noob from England

Cheers
Alex
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Old 02-08-2010, 10:05 AM   #2
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Pics of engine bay, Pics of your drain line too.
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Old 02-08-2010, 10:08 AM   #3
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Originally Posted by SKMetalworks View Post
Pics of engine bay, Pics of your drain line too.
No can do at the moment as car is 200 miles away at my specialist. I wanted to get your opinions too as I'm so frustrated with it all.

Drain line being block definitely not the issue - checked that!

Last edited by Mavalex; 02-08-2010 at 01:18 PM.
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Old 02-08-2010, 11:59 AM   #4
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its a bad seal on your chra probly man barring a drain line that is not totally vertical and clear that is the only solution i can see.
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Old 02-08-2010, 12:44 PM   #5
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^ yep

Blown turbo seals are awesome. I've had so many people give me the finger when I had to limp 50km home.
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Old 02-08-2010, 12:46 PM   #6
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Blown turbo seals are awesome.
Blown turbo seals are a myth, blown rings are a reality.
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Old 02-08-2010, 12:54 PM   #7
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Blown turbo seals are a myth, blown rings are a reality.
Sorry to potentially ask a stupid question but why do you say this? It seems a very sweeping statement...

Which rings are you talking about - piston rings? If so, why is the compression test result so good?
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Old 02-08-2010, 01:00 PM   #8
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we need pictures of your PCV line, the breather line, and your oil drain line.

Oil seals don't blow, they can however get overwhelmed and let oil past IF you happen to be pushing too much oil pressure against them. If this is the case and you are able to lower the oil pressure, the seal will be fine. Chances are this isn't the problem.

Sound like you blew out your compression rings. Your compression results are high, this is probably due to the extra oil coating everything and artificially bringing up the results. Do it again when the motor is warm, then drop in a 1/2 teaspoon of oil into each cylinder before you test again. post the results of the dry and wet tests.
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Old 02-08-2010, 01:11 PM   #9
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Ok, in lieu of pictures for now, oil drain is literally straight down from bottom of turbo then drilled into the sump (as suggested in the begi install manual).

PCV line is unchanged from stock.

The breather line runs a short distance into the begi provided elbow that has the little threaded fitting for this purpose.

My question is - if the compression rings are blown, and they are replaced will they simply blow again? i.e. is there a deeper seated problem that needs to be taken care of...?
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Old 02-08-2010, 01:19 PM   #10
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Meh, mine smokes a bit but I never have any oil loss when I do my oil changes...Pull off your downpipe and see if there is any oil deposits right after the turbine wheel.
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Old 02-08-2010, 01:23 PM   #11
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Meh, mine smokes a bit but I never have any oil loss when I do my oil changes...Pull off your downpipe and see if there is any oil deposits right after the turbine wheel.
I rinsed through 4 litres. lots of smoke! Surely there is guaranteed to be oil right after the turbine wheel seeing as it is seeping out of the union between the DP and the turbo outlet flange!
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Old 02-08-2010, 01:26 PM   #12
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Oh, then you are spewing out oil. Well, I'll leave it to the pro's on this one.
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Old 02-08-2010, 01:29 PM   #13
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What about wicked fucked valve guides/seals? The guides were so bad on my 1.6, that when I removed the engine and took off the exhaust mani, there was oil literally dripping down the stems of a few of the exhaust valves. Mine was smoking badly on the over-run after coming out of boost/going into vac.
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Old 02-08-2010, 01:33 PM   #14
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What about wicked fucked valve guides/seals? The guides were so bad on my 1.6, that when I removed the engine and took off the exhaust mani, there was oil literally dripping down the stems of a few of the exhaust valves. Mine was smoking badly on the over-run after coming out of boost/going into vac.
Would this not manifest itself as low results in a compression test? Or do you think a thick coating of oil (as braineack suggests earlier) could actually cause inflated compression results to mask this problem?
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Old 02-08-2010, 02:05 PM   #15
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Mine smoked badly from the cylinders and it showed good compression the whole time. To be certain it was the rings, I disconnected every line that could get oil into the intake (PCV, etc.), I then disconnected my turbo drain line and feed line and plugged it so no oil was going through my turbo (clamped wheel so it wouldn't spin) and it still smoked. That left only the valve guides and the oil control rings. Valve guides typically leak at startup (from oil dripping past the seals overnight) and high vacuum, but mine smoked at higher rpms. Pulling the spark plug to see oil smoke coming out of the cylinders confirmed oil in the cylinder. So I concluded my oil control rings (NOT compression rings) were the culprit. Again, I had 180-195 on all 4 cylinders and was losing lots of oil out the tailpipe.
My solution was to replace the engine. Works great now! I hope yours doesn't require that.
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Old 02-08-2010, 02:08 PM   #16
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car shouldn't smoke or burn oil at all; only the first time you start it up when you're burning off oil and crude from new parts.

if the valve seals were bad, it would only smoke at startup and under heavy vacuum.
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Old 02-08-2010, 02:11 PM   #17
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Mine smokes after I get going in gear after idling a while, and under heavy load.

I'm guessing it's the same thing as Clay's but that I'm also low on compression.

Either way I'm going with the same fix he did.
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Old 02-08-2010, 02:14 PM   #18
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Yeah, mine didn't smoke under load, just the over-run, going into vac.

Is it strange to lose the oc rings and not the comp rings? I don't know, just askin'.
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Old 02-08-2010, 02:16 PM   #19
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that's pretty much what I think happened to my rings. It held compression fine, but consumed and burned oil like a banshee. when we opened the block there was no signs of wear or failures.

either way, a healthy turbo setup should smoke 0%, 100% of the time. The only time you should ever see smoke is steam from the hood when it rains.
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Old 02-08-2010, 02:27 PM   #20
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Quote:
Originally Posted by webby459 View Post
Yeah, mine didn't smoke under load, just the over-run, going into vac.

Is it strange to lose the oc rings and not the comp rings? I don't know, just askin'.
Not strange at all, especially on our cars. That is how my engine bit the dust. Compression rings fine, all oil control rings were stuck in the fully compressed position and stopped doing their job.

Rings also get my vote.
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