Technical I am at my wits end Can anyone please help me out

[andy407]

Hi I have a Fiat Doblo 2007 1.3 multijet diesel with 64k on the clock. My issue is that when the engine gets warm i have a real bad squeaking noise coming from the left hand side where the auxiliary belts, water pump etc are and the noise will not go off until you turn off the engine and allow it to cool down, then restart it is quiet but as soon as it gets warm it starts again, and it sounds like a dry roller baring or a budgie being strangled. I have removed the belts one at a time expecting that this would stop the noise at some point, so that i could pin point the area that was in need of fixing. Unfortunately it hasn't sorted the issue even without anything connected to the belts so that nothing is running it still makes the noise, and i really don't know now which way to turn. I really could do with some sound advice and not the sort like take it to the garage as i am a fully qualified mechanic just in need of some guidance. Andy...

 

[portland_bill]

It might be the vacuum pump.

Diesel engines do not create a vacuum in the inlet manifold, so to work the servo brakes, a vacuum pump is fitted (also on most petrol turbos). This is driven by the camshaft. Find the brake servo, follow the big black air pipe from it back to the engine. Then listen to the thing the pipe fits onto.

These pumps can become loose, so check its mounting bolts.

If the pump is twittering at you, some noise is normal as the pump does its stuff, you then have to decide on live with it, or replace it.

If the noise is internal, have you checked the oil level?

 

[andy407]

Hi dude thanks for your reply i have had a screw driver on the vac pump and its not making any noise. As for the oil i have changed it today as i thought as the squealing was only happening when it come to running temperature it could be thin oil but yet it still squeals like a banshee. Andy........

 

[portland_bill]

If it is definitely not belt driven, this could be quite important. Especially as it occurs when warm.
More work with the listening screwdriver needed - take care around moving bits. Need to identify where.
Perhaps pop the cam cover off and check it is actually all oily in there. Oil starvation will make more noise as bits warm up and expand.
Also perhaps camchain tensioner? Camchains have failed on these, expensive.
Keep looking, good luck.

 

[jackwhoo]

Don't hate me for suggesting crank pulley.
If it's vibration damping pulley ,bonded rubber construction bonding could be failing
Or crank pulley rubbing on something .

 

[portland_bill]

Don't hate me for suggesting crank pulley.
If it's vibration damping pulley ,bonded rubber construction bonding could be failing
Or crank pulley rubbing on something .

Good thought.