P38A Diesel Turbo Squel

[Lukas018]

Hi,

Was driving home last night and when accelerating/engine under load i get a loud squel noise and dies down when not under load.

No smoke when accelerating, runs and drives fine. Looked at all pipe and no noticeable splits. Run engine inlet hose off exhaust on still makes noise when revved.

Noise is coming from back of engine not front as suspected belt and pulleys but they seem fine.

Anyone know what it could be or what I could check please?

Ta

 

[Henry_b]

More than likely the vanes in the Turbo..

Take the inlet off and give the vanes a jiggle wif ya finger!

 

[lynall]

Exhaust manifold gasket leaking, hence the squeak/whistle as the engine starts to work.

Of course if could also be range rover speak for kill me now please

 

[Lukas018]

More than likely the vanes in the Turbo..

Take the inlet off and give the vanes a jiggle wif ya finger!

Thanks mate, what am I looking for when checking vanes? Excessive movement?

 

[Lukas018]

Exhaust manifold gasket leaking, hence the squeak/whistle as the engine starts to work.

Of course if could also be range rover speak for kill me now please

Thanks will check the nuts as put new gaskets on a month ago.

My RR is cursed tho

 

[Henry_b]

Thanks mate, what am I looking for when checking vanes? Excessive movement?

Yep

 

[brianp38dse]

Thanks mate, what am I looking for when checking vanes? Excessive movement?

Just dont do it when the engine is running

 

[Lukas018]

Just the run with car without the turbo and exhaust manifold and whilst naturally loud noise the squealing went so can only assume turbo is at fault.

Vanes seem OK not moving around.

 

[Mark Piercy]

Check around the intercooler for hairline cracks and traces of oil misting.
There should be a tiny bit of play on the shaft in a cold turbo but not enough for the turbine to touch the casing around it. Try and see into it also for damage I. E broken fins.

 

[dubbleRR]

Exhaust manifold gasket leaking, hence the squeak/whistle as the engine starts to work.[/QUOTE I had that ,a leaking exhaust gasket squealed when accelerating hard ....Found some soot round the rear of the manifold ,The manifolds are also prone too cracking ,have a look for a hair line crack if uv got the manifold off .....RR..

 

[brianp38dse]

Is the oil supply to the turbo ok, as no oil = squeal
Thats how i diagnosed a duff oil pump on a bmw n47 engine that and it running ruff because the valve lifters were not pumping up

 

[Lukas018]

Thanks all. I took the turbo off and looked fine in good nick.

The supply is fine as I found out when run engine with feed undone and it shout out.

Only thing could be were the exhaust spring nuts where loose. Not sure how tight they need to be as near impossible to get a torque wrench in there?

Intercooler is ok.

 

[tomcat59alan]

Thanks all. I took the turbo off and looked fine in good nick.

The supply is fine as I found out when run engine with feed undone and it shout out.

Only thing could be were the exhaust spring nuts where loose. Not sure how tight they need to be as near impossible to get a torque wrench in there?

Intercooler is ok.

Is the steel "gasket" between the manifold and turbo ok?are the three bolts tight? 12mm bihex iirc.

 

[Lukas018]

Is the steel "gasket" between the manifold and turbo ok?are the three bolts tight? 12mm bihex iirc.

Yeah the gasket is about 3 months old, bolts were done up to torque.

 

[Lukas018]

A silly question, could it be a manual gearbox issue?

The noise was still there when clutch was down and disengaged just a long shot.

 

[tomcat59alan]

A silly question, could it be a manual gearbox issue?

The noise was still there when clutch was down and disengaged just a long shot.

Dry release bearing?

 

[Lukas018]

Dry release bearing?

Sorry for being stupid does this spin even when clutch is down?

 

[Mark Piercy]

Sorry for being stupid does this spin even when clutch is down?

All the time, it sits up against the pressure plate. Normally will make a noise when not under pressure and goes quiet under pressure. Whereas a dual mass flywheel can make a noise when not under pressure and also under pressure.

 

[Rubberknees]

Just something to look for years ago I had a SD1 Rover with straight 6 engine which started squealing on gear changes and at certain position of throttle. Changed clutch ,thrust bearings plus other related bearings. Turned out to be blown gasket on inlet manifold sucking air, hence the whistle. Just a thought. Cost £1 for new gasket

 

[Lukas018]

All the time, it sits up against the pressure plate. Normally will make a noise when not under pressure and goes quiet under pressure. Whereas a dual mass flywheel can make a noise when not under pressure and also under pressure.

Thanks Mark let's hope it's not that. Took turbo and manifold apart and started to reassemble it.

How tight do the spring nuts need to be where exhaust connects to turbo as I cannot get a torque wrench in there?