X20XEV Ecotec "Screeching" Help!!!!

[ecotec2.0auto]

Hi. Firstly, I'm new to the forum so hello everyone. There certainly seems to be some great info on here. I have a 2.0 Ecotec GLS Auto in Polar Sea Blue. It's been in the family from new and has 86k on it. It's generally in very nice condition indeed, almost rust free and used lightly all it's life.

The problem i have is a screeching coming from front end of the engine, not dis-similar to that you'd get in the good old days of loose fan belts. I suspect there could be a number of potential causes. I have so far done the following work to try and eliminate it but it's still there:

New alternator (got a genuine new GM ex unit for £40, the bearings in the old one were a bit iffy so changed it anyway)
New aux drive belt
New aux drive belt tensioner (bearings were a bit iffy in this unit too)

The screech seems worse when the engine is idling, and is not apparent over around 1200rpm. when idling it becomes stronger when the steering is turned. I'm inclined to suspect it's not the steering pump (but don't rule it out) but an effect of the additional load placed on the engine when the steering is on lock.

I guess the only suspects remaining are:

Damped auxiliary drive belt front pulley (at the bottom of the engine)
Water pump
Timing belt tensioner
Power steering pump

It's a really irritating sound and can be quite embarrassing when the car is sat idling somewhere!

I can go on chasing the problem by replacing things randomly but could really use some advice from you guys if this is a common or known problem. Otherwise the car starts, drives and does everything else extremely well.

Cheers

Paul

[Gaz]

uhook the belt out of the way of the bottom pulley and run the engine does it still do it (im betting it wont)

[planetc]

Firstly, as Gaz said confirm it is definitely belt related by running the engine with the belt off.
I put a new belt on mine, and a few days later fitted a new inlet gasket. I was being lazy not removing the belt and ended up with the alternator a tiny bit crooked. This caused the belt to rub the edges of the v's slightly. I didn't do anything about it for a couple of weeks, by which time the new belt had worn enough that I had to replace it again.
My point is that if anything on the belt run is out of line the belt will wear at a ridiculous rate. Check everything for alignment and replace the belt when it is confirmed to be good.

The other thing to bear in mind is that a restriction in the oil pickup pipe can cause a screech that sounds very much like a belt slipping.

[ecotec2.0auto]

Chaps

Just had a thought.......when the belt was off, the outer lower pulley would rotate somewhat. I'm guessing it shouldn't do that as the damping layer should be bonded?

If that's the case then it's almost certainly the pulley.

I'll drop the belt off as advised to confirm it first.

Next question. Are replacement pulleys really as expensive as the ones on e bay would have you believe (pattern parts by Gate for around £160). Seems seriously steep to me!

Thanks again for the advice.

Regards

Paul

[planetc]

Yep, it shouldn't rotate as it's bonded to the inner.
Shop around, last one I bought came from a vauxhall specialist place which I can't remember the name of, but it was about £30

[ecotec2.0auto]

I though £160 was a bit silly!

Thanks for that chaps.I'll let you know how i get on. I'll stick some pics of it on here as well shortly!

Cheers

Paul

[ecotec2.0auto]

Found a new pulley for £47, which is more realistic....

.....next question, does anyone know the latest part number for the 4 securing bolts. The ones on it have the Torx tupe heads.

Cheers

Paul

[Gaz]

just use normal bolts i have

[ecotec2.0auto]

All sorted!

Even got the new bolts from Vauxhall. It's now runnin g/ driving like a 2 year old car (seriously), and whisper quiet. Took it on a 90 mile round trip to work today, including a 90mph blast round the M25 and it's back to it's old self.....happy days!

Thanks for your assistance chaps, much appreciated!

Paul