The Cal-look Lounge

 I have a turbo efi motor in my bus.

Recently blew oil out the blow off valve, I have taken the turbo off and there is oil in the air inlet/outlet and exhaust. Took it to a turbo reconditioners to check over who said it was OK.

He believed that it would be more engine related, piston rings or similar and I should check the compression first.

I have started to re install things and upon checking the exhaust header there is no trace of oil anywhere, and only traces of oil can be found in the intake system after turbo.

Now I'm no turbo expert but I suspect its the oil seals in the turbo that have failed. Just wanting some advice before I take it elsewhere to check again.

Thanks

You must explain which brand you are using
Some units need oil reduction, others you must have back pressure in the exhaust system for the sealing ring to work (is like a piston ring) If there is too much pressure, there will be oil in the compressor Other units must have back pressure in the turbine side so the compressor can keep tight from oil in the bearing housing
/// Micke

Thanks

There are no manufacturers markings on the turbo so don't know the details of it. I know it's oil and water-cooled which is about all I can offer.

I appreciate the points you raised around the different styles but surely would only find oil in one outlet not all 3.

Then it is very difficult to help you when you do not know what the brand is
Then I saw you had asked on another thread how low the agge can sit
If it is too low, the oil will not come out and the oil will go the easiest way, it is behind the compressor wheel
  If there is too much internal pressure in the engine, the oil comes out at the compressor and the pressure pipes become filled with oil
I usually tell those who are going to mount the turbo there because there will be problems free
The center of the turbo shall not be lower than the center of the crankshaft
That during it it is easy to become a problem if you do not use a suction oil pump that diverts the oil from the turbo
  So they did on posche 911 turbo (dry sumps pump
/// Micke

Thanks for the reply again.

I purchased the bus that the engine is in last year and I have been trying to get my head around the set up and rectify any niggling problems that arise.

The exhaust is custom made and sits the turbo to the left of the engine as you look from the rear, the oil return from the bottom of the turbo drops into a reservoir and is pumped back into the case with an electric pump. Seems to comical things which is why I created the other thread about oil return.

I have added a few pics of the set up.

[attachment=1]
[attachment=2]

Take the header off and look for oil in the exhaust ports

There's only carbon, no trace of oil.

Then it's the turbo. Take is somewhere else

Some turbos need an in line oil pressure restrictor to stop oil overwhelming  the oil seals. Do you no the oil pressure is from cold.. Especially  the oil pipe to the turbo.

Dont know the oil pressure cold, ill have to check my gauges but haven't noticed anything abnormal.

Your turbo is so low that you will need the suction pump or move the turbo higher.

Has this engine work properly before?

I have owned the bus for coming upto 18 months, it ran well with no engine related issues until a week ago when it ejected a quantity of oil from the blow off valve prior to the charge cooler.

When I have then parked the bus up and removed the exhaust and air inlet/charge pipes there was oil present on every outlet.

As mikko says. If the return is going up hill there's no chance of working correctly

That's why I'm presuming they fitted the drain tank below the turbo fitted to an electric pump returning it to the engine case.

I have checked the oil pressure when cold and its in the region of about 40 psi.

I'm presuming the best option would be to fit a new purpose built turbo manifold to correct the turbo positioning.

Yes. Vw turboing isn't easy, it takes a lot of forward planning and changing things around till it works. It's a good hobby though. Theres a good sense of achievement when you've ironed out the issues.

One of these perhaps?
https://www.turbosmart.com/news/save-your-turbo-opr-t40/

Id also suggest that you check the pump that pushes the oil back up into the sump.
HTH