My Citroen XM 3.0 PR-Vestige

[Dieselman]

I've changed my belt today and it haas stopped the chirping.

New belt 10mm wide and sits at the top of the V. old belt worn down to 7mm wide and sat 1/2 way down V.

In my experience, as long as the belt sits at the top of the v, all will be well, once they drop below the top they are finished and give constant problems.

[White Exec]

But won't a new belt work ok anyway, until it doesn't?
Did the 7mm belt start life as 10mm?
Doesn't sound as if the issue is really being addressed.

[Dieselman]

Umm.

yes
yes
All belts wear. These work fine until they wear.

[Dean]

All my belts start out fine and the same width (10mm) they survive idling on the drive and even short jaunts around the block a couple of miles or so but as soon as i do a journey, even tensioning the belt before leaving, it just gets eaten.
It's working again fine now, no problems at all but i will have to see what happens when i go on a long journey next, i have reduced operating pressure back down to 175bar despite the guys at Plaiedes saying it won't make any difference.
I'm pleased Will is having the same problem (sorry Will), it's confirmed that i do not have a problem other than a belt drive running on the ragged edge of what it can cope with load wise.

I will see tomorrow how successful I have been and at least soon i shall have some more spare belts.

D

[Dieselman]

[quote="Dean"
I'm pleased Will is having the same problem (sorry Will), it's confirmed that i do not have a problem other than a belt drive running on the ragged edge of what it can cope with load wise.

[/quote]
I believe I've only had this issue because there was no tensioner bolt in the bracket, so the belt wore. onece the belt has thinned there's no going back, it will just continue to wear rapidly due to A; the lesser contact patch, B; the smaller pulley diameters as it is now deep in the v.

I don't believe I will have a further issue now I have fitted a new belt that rides at the very top of the pulley v.

System pressure will make a difference for two reasons; 1. the pump will be harder to turn. 2; the duty cycle will be greater as it takes longer to pressurise from 145 bar to 180bar than from 145 Bar to 175 Bar.

[djg]

Really a shot in the dark but couldn't it be the pulley and whatever is on the other side not being completely aligned? If I were a belt, I certainly wouldn't like being forced to the side, out of my comfort plane.

[White Exec]

...and are the pulley sides at all abrasive? Should be mirror smooth, after years of use.

[Dean]

Dean,
might a belt tlike this be useful to you? Apparently it can transmit more power than normal...

http://www.bearingoptions.co.uk/v-belt- ... 0548-p.asp" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Are your belts definitely 10mm x 670mm? If they are narrower they will not be able to transmit as much power and will move down into the pulley v and wear rapidly.

The one on my car is chirping again and I'm sure the tensioner bolt hasn't moved, but the belt is wearing thinner.

Arrived today, they are Dunlop branded belts, they are a very hard compound and the teeth are very small, the belt is rather shallow too, just going to fit one now.

D

[Dean]

...and are the pulley sides at all abrasive? Should be mirror smooth, after years of use.

Mirror smooth is pushing it a bit, they have progressed from hull plate of the Titanic to 6 month old Maestro levels of crust but they will bed in, the issue only arose after a bit of use though, as the pulleys started to clean off.

D

[russ92xmsed]

Interesting about the compound of your new belts. I refitted an older belt to mine not long ago, and it stopped chirping and the hydraulics were far better. That was noticably tougher and had different teeth to the others I had.

Hopefully yours will work.