V6 Petrol Noise When Warm

[Tigmaster]

Hi all
as per subject I have a 99 V6 petrol with 100km.
Recently changed auxiliary belts and replaced one of the tensioner bearings as it felt rather dry.
Timing belt was changed a year before I purchased it. Im not sure if the timing belt pulleys were changed.

Engine runs really nice.
However, when the engine gets up to temperature I get a slight squealing noise when I put my foot on the accelerator.
This is mainly from around 1800 rpm in any gear.
Mainly occurs when driving in a straight line, sometimes if I am turning the noise isn't there.

I cant remember if the noise was there before I changed the belts as I serviced and changed belts etc straight away upon purchasing the vehicle.

On researching I am guessing it could be one of the following:
Water pump bearing
tensioner bearing
air con / alternator / steering pump bearing
belts need to settle in (cant really see this one)

Does anyone have any suggestions?
What is the best way to determine which of the above? It doesn't make the noise when stationary.
Although I heard it a couple of times if I had it in drive with all the brakes on and revved the engine.
So I cant get close to the components when its making the noise.

Is it likely to be one of the above and not timing belts pulleys?

Regards
Sean

[g8dhe]

Might be worthwhile checking the tension of the two aux. belts as a start before getting any deeper as anything else at the front of the engine means taking a lot of things off!

I have heard people suggesting spraying each aux. belt in turn with water to see if anything changes - not something I've tried merely reporting what has been suggested elsewhere!

[Tigmaster]

I removed the air con belt - noise was still there
I then removed the main auxillary belt and the noise went.
The tensioner pulley bearing was replaced a little while ago and seemed perfectly ok.
Alternator & power steering pulleys seem ok.
Whilst the engine was still hot i spun the water pump and it sounded a little dry / squeak noise.
It seems to have a bit of play in it but generally feels ok when cooled.

The fact that the noise only appears when it gets warm and over 1800 rpm leads me to think its the pump.
So I have drained the coolant, removed the tensioners and the main plastic timing belt cover.
I am struggling to remove the smaller one though.
The 2 bolts that hold the dip stick tube in place have been removed and the tube turns but wont come out.
Does anyone know if i need to remove the distributor & top alloy timing belt cover to remove the plastic section?
Or how does the dipstick tube come out?