Diesels squeal under load- Why????

[stigproducts]

Diesels which squeal when the engine is put under some load. What makes this noise and how is it eliminated?
I thought it was teh alternator drive belt but i have adjusted mine with no difference seen.

[annodomini2]

Diesel Injection pressure is somewhere between 400 and 2000 bar peak depending on the type of system used. Could be this, is it turbo, could be turbo whine they usually spin at around 100,000rpm.

[wadgebeast]

If it's the turbo, it'll normally whistle...

Not the fan belt slipping?

[stigproducts]

Hi, it hasn't got a fan belt like a v shape. it is one of these toothed belts I think. I tightened it up as much as I dare but it has made no difference. Yes it is a turbo.

[fangio]

You can check if it's the belt by spraying it with WD40 while it's ticking over.

[combemarshal]

I wouldn't use wd40, I know that it eats rubber seals on suspension seals on Motorbikes, hat to think what it would do to a belt!
Water should have the same effect, and if you want bubbles just add fairy liquid!

[tvrgit]

Talcum powder.

[GreenV8S]

Oh no, don't spray WD40 on anything rubber, and I'd stay away from talc, soap and stuff like that intended to make the belt slip. Get some belt dressing spray and give it a dose of that, it'll make the belt grip better, preventing it slipping and preventing the noise that occurs when it slips.

[stigproducts]

Got a bit of an oil leak down there- that will explain it. It's time for new belts anyhow so a tidy up will be in order.

Thanks.