Turbo experts help please...

[davek0974]

Hi all,

following on from my various endeavours to trace the missing get-up-n-go in my 1994 disco 1 300tdi, i fitted a pressure gauge reading 0-30 psi. I tee'd it into the pipe going from turbo to injector pump. I used a 0-30 gauge as the target pressure (boost) was around 12psi which is at the most accurate mid-scale point of the gauge.

Anyway, we took her for a spin with wifey holding the gauge shouting out numbers as i thrashed (or attempted to) the nuts off of her, warmed up, then uphill as full throttle as i could get.

The maximum boost i got was 2 psi so if i did the test correctly, this would indicate why she is as flat as a pancake to drive, lifeless is an exaggeration here.

So the question is, WHERE HAS ALL MY PRESSURE GONE????

It makes the right whistle noise as you rev but there is bugger all pressure output.

ANY thoughts would be much appreciated.

Dave

[BogMonster]

Take the intercooler hose off the inlet manifold and rev the engine briefly you should get a hurricane of air out the end of the hose if the turbo is working.

[davek0974]

Take the intercooler hose off the inlet manifold and rev the engine briefly you should get a hurricane of air out the end of the hose if the turbo is working.

Just got off the phone with a mechanic, apparently all the turbo's that he has seen would spin very freely if the rotor is flicked by hand.

My one is physically quite stiff and although it can be turned, it most definately would not spin.

Sound like a partially seized turbo??????

[Les Henson]

Yes, the turbo shaft should spin very easily and have a small amount of play in the bearing. Strange - I've not come across a siezed turbo before. Oil is forced through the bearing all the time the engine is running, so siezure would be very rare.

Les.

[redneck]

One problem with turbos is that the oil can burn on the bearing/shaft when the engine is shut down after a high speed run. Stopping for fuel on the motorway for example, this in turn leads to a build up on the shaft/bearing which could slow it down.

Might also be carbon build up on the exhaust side.

Either way it's a strip/rebuild or replacement.

[davek0974]

One problem with turbos is that the oil can burn on the bearing/shaft when the engine is shut down after a high speed run. Stopping for fuel on the motorway for example, this in turn leads to a build up on the shaft/bearing which could slow it down.

Might also be carbon build up on the exhaust side.

Either way it's a strip/rebuild or replacement.

Thats what i thought, its blowing oil anyway so i have a 2nd hand one coming with a money-back cover so i'll only lose the P&P which is ok, Cant afford a recon unit.