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Rebuilt k27 7006 f$&@ed

I have installed my rebuilt k27 and have oil pushing out through both sides, turbine into the exhaust and compressor into the intercooler. There was an oil slick on the garage floor 3 foot plus long from the exhaust and new clean oil leaking back down from the intercooler.
I tested the scavenge pump and it appeared to be fine as it was pumping oil well when tested. I spoke to the rebuilder and they want a compression test for some reason yet the engine starts fine and does not run rough it is running on all six. My mechanic said there is nothing wrong with the compression. So even if there was a hole in a piston or oil getting past the rings it could not pump this much oil into the exhaust.
The rebuilder has said it is unlikely to have both seals fail, my mechanic feels it's the turbo.
Any other ideas would be appreciated before I remove the turbo again. At least it will be a lot easier to remove this time as I only ran it for 5 to 10 minutes and did not drive it.
Old 03-23-2017, 08:42 PM
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I had a similar problem once.

The culprit was a loose oil line between the Turbo and the scavenge pump. It was sucking air, not oil.

Check your fittings.
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Old 03-23-2017, 09:02 PM
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Quote:
Originally Posted by unclebilly View Post
I had a similar problem once.

The culprit was a loose oil line between the Turbo and the scavenge pump. It was sucking air, not oil.

Check your fittings.
+1 on this. Experienced this first had late last year. If it's pushing that much oil like that it's worth it to remove the turbo and clean it all out.
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Old 03-23-2017, 09:05 PM
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I will check the fittings tomorrow, if the joints look OK is there a way to check if they are sucking air.
Old 03-23-2017, 09:57 PM
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Put a wrench on them and try to tighten them.
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Old 03-23-2017, 09:58 PM
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If they bought the rebuilt kit online, it almost certainly was a Chinese knockoff and this is often the result. There are a few reputable turbo rebuilders out there that will not use the cheap crap. Durabilt is one of them and where I sent mine.

Ask where he got his parts to rebuild your turbo.

Does your catch can have a vent? If so, that is where excess oil should go if the scavenge pump fails or there is an air leak. If you tested the scavenge pump and didn't disconnect it afterward, its probably not that.
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Old 03-23-2017, 10:15 PM
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Quote:
Originally Posted by Jeff NJ View Post
If they bought the rebuilt kit online, it almost certainly was a Chinese knockoff and this is often the result. There are a few reputable turbo rebuilders out there that will not use the cheap crap. Durabilt is one of them and where I sent mine.

Ask where he got his parts to rebuild your turbo.

Does your catch can have a vent? If so, that is where excess oil should go if the scavenge pump fails or there is an air leak. If you tested the scavenge pump and didn't disconnect it afterward, its probably not that.
Hi Jeff
To test the scavenge pump I removed it and made a dowel/key attached a drill to it and a couple of hoses with one end in a bucket of oil and it surely pumped plenty of oil.
The catch is a stock tank and I am guessing only, that the brass line from the side near the top is a breather?

Old 03-24-2017, 01:16 AM
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Dropping one of the heat exchangers will verify that your engine is not the problem. For someone to even say such a thing is suspect. The first thing I think of when a rebuilt turbo blows oil is not "the engine is blown". Check the cheap stuff first, don't scare people to death thinking they have a $25K rebuild coming.
> why was the turbo rebuilt to begin with? If it was blown, why was it blown?
> verify the turbo wasn't run dry at start up (not likely)
> verify all turbo oil lines are connected properly, tight, and not kinked.
> verify oil flow to the turbo is not more than oil flow back to the pump.
That really is about all you can reasonably do, and you've done those things. The turbo needs rebuilt but you sure don't want to put a rebuilt turbo back on just to have it blow again because the problem is with the oil system and not the turbo.
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Old 03-24-2017, 05:06 AM
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Quote:
Originally Posted by RarlyL8 View Post
Dropping one of the heat exchangers will verify that your engine is not the problem. For someone to even say such a thing is suspect. The first thing I think of when a rebuilt turbo blows oil is not "the engine is blown". Check the cheap stuff first, don't scare people to death thinking they have a $25K rebuild coming.
> why was the turbo rebuilt to begin with? If it was blown, why was it blown?
> verify the turbo wasn't run dry at start up (not likely)
> verify all turbo oil lines are connected properly, tight, and not kinked.
> verify oil flow to the turbo is not more than oil flow back to the pump.
That really is about all you can reasonably do, and you've done those things. The turbo needs rebuilt but you sure don't want to put a rebuilt turbo back on just to have it blow again because the problem is with the oil system and not the turbo.
Hi RarlyL8.
To clarify your points -
> the turbo was rebuilt due to the tip of an old air injection nozzle (that should have been removed when deleting the smog stuff) broke and damaged the turbine wheel.
> before start up the turbo was primed with liquidmolly, I removed power to the fuel pump and cranked the engine over a few times.
> all plumbing appears to be ok.
> the last point however I am not sure about. I have checked to see if the scavenge pump works but have no idea as to whether the oil flow to the turbo is more than the oil flow back to the pump.

Is there a way to verify that the oil system is working correctly?
Old 03-24-2017, 08:32 AM
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Remove the oil pickup to the drip tank and put that line into a bowl. Let the engine drain from tank into same bowl. The amount of oil should not raise in the bowl. It the oil raises faster than the scavenge can suck it up the scavenge is faulty. Could be a bad pump(unlikely) or an airleak in that line to the scavenge pump.
FYI I had debris from intake side of turbo take out the turbo...and somehow my scavenge pump was damaged (probably from a ball bearing) leading to this condition. Had to replace my scavenge.
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Last edited by quattrorunner; 03-24-2017 at 09:25 AM..
Old 03-24-2017, 09:21 AM
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Quote:
Originally Posted by quattrorunner View Post
Remove the oil pickup to the drip tank and put that line into a bowl. Let the engine drain from tank into same bowl. The amount of oil should not raise in the bowl. It the oil raises faster than the scavenge can suck it up the scavenge is faulty. Could be a bad pump(unlikely) or an airleak in that line to the scavenge pump.
FYI I had debris from intake side of turbo take out the turbo...and somehow my scavenge pump was damaged (probably from a ball bearing) leading to this condition. Had to replace my scavenge.
Thanks for the info mate.
I will do the test this weekend.
Old 03-24-2017, 09:45 AM
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Originally Posted by SBK930 View Post
Thanks for the info mate.
I will do the test this weekend.
The problem is that now that oil is going everywhere, you are going to make a mess when you run the car again...

And maybe someone with more experience can chime in, but if the catch can is vented like the OEM one is, how would it build up enough back pressure to push oil through the turbo seals? Wouldn't the oil just go out the breather, especially at idle?
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Old 03-24-2017, 10:41 AM
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^^^

If the trubocharger was built poorly enough (like my HyFlow originally was - likely way out of balance) that the bearings got damaged right away, then oil goes right past the seals with very little resistance.
Old 03-24-2017, 10:48 AM
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And my drip tank isn't vented not sure if that really has some effect.
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Old 03-24-2017, 11:12 AM
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Quote:
Originally Posted by Jeff NJ View Post
The problem is that now that oil is going everywhere, you are going to make a mess when you run the car again...

And maybe someone with more experience can chime in, but if the catch can is vented like the OEM one is, how would it build up enough back pressure to push oil through the turbo seals? Wouldn't the oil just go out the breather, especially at idle?
And that breather vents through a hose to the air cleaner box I think. Which I will mention does have some oil through it now.
Old 03-24-2017, 12:48 PM
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Quote:
Originally Posted by Rawknees'Turbo View Post
^^^

If the trubocharger was built poorly enough (like my HyFlow originally was - likely way out of balance) that the bearings got damaged right away, then oil goes right past the seals with very little resistance.
The rebuilder tells me that it was balanced and tested to retain and not leak oil.
Well it is certainly leaking now, lots of the stuff. I would say after the short run there was a quart on the floor and as much now sitting in the bottom of my monty muffler.
Old 03-24-2017, 12:53 PM
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Question

For those that understand turbos better than I , what other reasons could there be for a turbo to have oil pressure that blows past the seals
Old 03-24-2017, 11:33 PM
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^^^

There really is no other reason other than something wrong with either the turbocharger , scavange pump, or oil return hoses/pipes. The oil supply to the turbo has a lot of volume, but not a lot of pressure (not going to blow seals out with oil supply pressure, in other words).

Like others have mentioned, you need to first verify that the scavenge pump matches or exceeds the oil supply volume, and if it does, then the turbocharger needs to come out and apart (regardless of what the rebuilder is saying).
Old 03-24-2017, 11:54 PM
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I had a similar issue in that the scavenge line had to be primed. The best way to confirm is as previously mentioned. Have turbo drain into a bowl and have to scavenge pump pipe suck from the same bowl. If that works correctly it then appears to point to the turbo. In the end I raised the back end of car and filled the scav pipe. Connected all up and cranked it as you did earlier. It then all worked.

Good luck.
Old 03-25-2017, 02:51 AM
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OK today, to check the oil flow I will remove the plug/bung in the bottom of the drip tank and allow the oil from the turbo to flow freely into a container and securely fit a hose to the scavenge pump oil line.
And hope I can see the flow through the smoke.

Will post what happens and Thankyou all for the help.
Old 03-25-2017, 10:53 AM
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