20v keep blowing turbo, help please

[K Simmonds]

Yes and no. I bought engine from s2 n300 which was out of the car already and fitted it into my ur quattro and turbo was smoking almost after first start up. After few runs it was more and more smoke. But symptoms was same or similar.
Is it possible that oil i'm using 20/50 to thick and not lubricating enough or causing other damage?

20/50 is on the thick side but I really can't see it causing the problem unless you consistantly thrashed the pants off the car when stone cold, once up to operating temp it should be fine.

[george21]

Are we right to assume that the stock turbo died a death of the same problem on a stock engine prior to modification?

Yes and no. I bought engine from s2 n300 which was out of the car already and fitted it into my ur quattro and turbo was smoking almost after first start up. After few runs it was more and more smoke. But symptoms was same or similar.
Is it possible that oil i'm using 20/50 to thick and not lubricating enough or causing other damage?

[george21]

In that case I also doubt the software is causing this to happen, anyway if I read right it did the same thing with another turbo and different software. Which means it must be something to do with hardware, but what

Just a thought, have you tried another wastegate? In theroy it could be sticking and causing the turbo to overspin.

You are right this is very very frustrating, i blew first turbo, thought ok, it is an old one and gave up, then done a volvo k24 setup (prj map)= blew up, ok it is and old turbo as well and then bought this k27/26 new one and it did again!!
After volvo turbo failure i start changing parts like n75, dump valve, checking oil pressure, breathing system and so on and on.
At the moment i fitted standard aby turbocharger until i figure out what it's bloody wrong with it. Even thinking to pay somebody to help me out as i run out of ideas!!
Maybe mr Brian(tonks) fancy a lovely job ?!

[twoqu]

Are we right to assume that the stock turbo died a death of the same problem on a stock engine prior to modification?

[newsh]

I thought about what you asked and NO i am not using one way valve, just an oil breather one end is in the block other end into the maf hose. I thought i don't need one way valve as i am not using carbon canister and n80. Am i wrong there?

That should be fine but it would be better to have a catch can in between. The good thing is that there should be no way for boost pressure to get into the crank case as the maf hose is always under vacuum.

[george21]

You must be going mad.
What would happen if oil thermostat was jammed open/closed?

Can you fit an oil pressure send before and after turbo to monitor whats going on across the turbo?

Why you think i'm going mad
I don't think there is a point fitting a pressure gauge after turbo as there will be no pressure, it is a free flow to the sump.

[george21]

Good point, are you still using the one-way-valve in the PCV system? The one under the inlet manifold near the throttle body?

I thought about what you asked and NO i am not using one way valve, just an oil breather one end is in the block other end into the maf hose. I thought i don't need one way valve as i am not using carbon canister and n80. Am i wrong there?

[martinws]

You must be going mad.
What would happen if oil thermostat was jammed open/closed?

Can you fit an oil pressure send before and after turbo to monitor whats going on across the turbo?

[K Simmonds]

In that case I also doubt the software is causing this to happen, anyway if I read right it did the same thing with another turbo and different software. Which means it must be something to do with hardware, but what

Just a thought, have you tried another wastegate? In theroy it could be sticking and causing the turbo to overspin.

[george21]

This problem must be very, very frustraiting!

On the breather system I wouldn't vent it to atmospheare, you really want the vacuum from the engine to keep air pressure in the crank case negative. A well thought out catch tank set up is the solution here, I don't think it's your problem though.

What software having you been using with the K26/7?

I sent ecu to prj and told him specs.
I don't think it is a breather as well, but everything have to thought as simply i CAN NOT afford blowing any more turbos!

[K Simmonds]

This problem must be very, very frustraiting!

On the breather system I wouldn't vent it to atmospheare, you really want the vacuum from the engine to keep air pressure in the crank case negative. A well thought out catch tank set up is the solution here, I don't think it's your problem though.

What software having you been using with the K26/7?

[george21]

first of all thank you very much guys from trying to help me!
oil return pipe was checked and cleaned and fitted back in, original aby pipe.
regarding sump breather system i raised this question myself, if it is to much blowby through piston rings and bad ventilation you will get a counter presure in the sump, stoping oil draining from the turbo. but how do i test that?
at the moment i have installed new one way valve and conected to maf hose as per original, just n80 valve not connected enywhere, just electrical conection pluged in, but no wacuum pipes pluged in as nowhere to plug it them as engine fitted to the
ur quattro, no carbon canister. shall i chuck everything out and leave just an open pipe without any valves etc, breath to atmosphere?

[newsh]

Good point, are you still using the one-way-valve in the PCV system? The one under the inlet manifold near the throttle body?

[caterpillar]

2 things: the oil RETURN side, are this ok, collapsed rubber...or is it metal pipe??.... next... the cranccase ventilation... the blowby in crancase... how are this solved.. the pressure from blowby, MAY give this problem...the pressure are so high, the oil cant go in the turbo, because the backpressure from the returnpipin, will not aloww the oil goin in the turbo... and the last what oilpressure are you have in the enhgine

[twoqu]

Cold side shaft bending could be due to overspeeding. It would be bent from the thrust shoulder up.
Of course its often difficult to tell what failed first! As you have said effectively the centralisation of the shaft is basically down to the oil, so any disruption in the supply would cause issues.