Transit died- are these symptoms a blown turbo?

[Aprisa]

Hi
Our transit went U/S last week and I suspect the turbo, the symptoms are:- complete loss of power on the motorway whilst going up a long hill, oil blown out of the breathers over engine and oil thrown down and out of the exhaust. Once cooled the engine starts and runs fine and sounds good. The problem then repeated itself after driving another three miles.

Any other opinions before I lay out for a new turbo?
thanks Nick

[mrsd]

Cracked oil gallery somewhere ? Of course, that's worse than a dead turbo

[deltaf]

Dont see how a blown turbo is going to put oil out of the breathers....or over the engine.
???
You sure you havent got a pipe off/cracked somewhere?
Best bet is to clean the engine off, then run it stationary and see if any oil is leaking out of anywhere.
Almost sound like a cracked/blowing boost pipe, but i cant see where the oil would come from.....
Hope this helps.....??? (scratches head vigourously!)

Ps. remove the intake pipe and see if the turbo impeller is free to turn...there shouldnt be any real resistance, and also check for radial play. There should be a little bit, but not a lot.
Does it blow smoke? Lots of smoke would indicate a blown turbo oil seal.

>> Edited by deltaf on Monday 23 June 11:14

[annodomini2]

If it's blowing out of the breathers, wouldn't it be piston rings with the engine over pressurising the block?

[aprisa]

Thanks so far, the reason I thought it was the turbo rather than other forms of engine failure is that when cool the engine is sweet as a nut, I thought if the turbo had seized when hot then the back pressure of not being able to allow gasses down the exhaust would pressurise the crankcase and also give the complete loss of power and stalling when clutch depressed.

Am I way off?

[deltaf]

Lol miles mate!
Usually a "blown" turbo equates to the oil seals leaking and burning oil in the exhaust, or a seized bearing causing no boost and associated power loss.
If the turbo had seized you would indeed get excessive backpressure, but itd tend to stall the engine rather than blow oil out anywhere.
Sounds a weird one considering that its ok when cold.
If theres oil blasting out the breathers, id say it was a piston/rings...but without hearing it/seeing it, dunno for sure.

[GreenV8S]

On a normally aspirated engine with the breathers plumbed in to the inlet manifold I think you would expect to find two breathers, a small one to the plenum for part throttle work and a larger one to the throttle for full throttle work. If the larger one was blocked, the crank case might tend to pressurize under prolonged full throttle, eventually blowing oil out. Don't know how well this translates to a turbo installation but your symptoms do sound like this sort of minor problem rather than terminal mechanical failure.

[Mr2Mike]

Aprisa said:

Hi Our transit went U/S last week and I suspect the turbo, the symptoms are:- complete loss of power on the motorway whilst going up a long hill, oil blown out of the breathers over engine and oil thrown down and out of the exhaust. Once cooled the engine starts and runs fine and sounds good. The problem then repeated itself after driving another three miles. Any other opinions before I lay out for a new turbo? thanks Nick

Partial siezure of one or more pistons? If the rings have broken due to this then you would have excessive blow by which could cause oil to be blown out of the breathers.

[360N-GT]

Easy things to check are, has it been over filled with oil? Is your fuel all OK?

Wash it all down really well, look inside the pipework..upstream of the turbo (pressure side) and clean all the oil out from there.

Run it a while to see if oil leaks outside or from the impellor seal into the inlet side, or into the exhaust side.

Do a compression test AND a cylinder leakage test.

[wedg1e]

Cracked cylinder head? Blown head gasket?

[sevans]

Had exactly these symptoms on a Sierra Cosworth engine. The seals had gone in the turbo. It dropped the oil into the exhaust but didn't burn it until the exhaust got hot. Check the breathers. If the turbo oil returns to the sump then any blockage or pressure in the sump will cause back pressure in the turbo. Worth checking the side movement on the turbo shaft, there can be quite a bit of play but it shouldn't touch the housing and there should be no end play.