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Discussion Starter #1 (Edited)
2.4 AAB (1997)

Alternator belt clatters very loudly between the bottom pulley and the water pump:-

Does not do it at constant revs or at idle but sounds bloody awful on 1st turn of the key, when turning the engine off & also as the revs drop just before settling to idle?
I’ve had the van 3 months & I think it’s always done it, hard to be sure as weve only done 600 miles in that time.

Tensioner plastic wheel is new & the tensioner arm feels OK, by that I mean I can’t feel any sideways play in it & the spring feels like it has significant resistance, I don’t think any rattles or noise is coming from the tensioner itself either.

Water pump & alternator pulleys run freely & I can’t feel any sideways slack.

Will I have to replace the tensioner to eliminate it or is there anything else worth checking?

How do I separate the arm from the tensioner? There are two allen screws that retain the tensioner into the cast bracket plus one in the centre of the tensioner itself, I have removed the centre screw but the arm won’t budge & I’m sure I can’t remove the tensioner without 1st removing the arm?

Any advice appreciated.
 

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Discussion Starter #3 (Edited)
Is the belt routed correct. If someone has put new pulley on and got the belt wrong

Sorry, not sure I understand how it could be miss-routed The belt goes around the bottom pulley, the water pump pulley, the altanator pulley and is held in tension by the sprung tensioner pulley?
Surely the only way it could be miss-routed would be to miss one out? Have I miss-understood
 

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Discussion Starter #5
Re: 2.4 AAB Alt belt clatter (pics added)

On the 2nd picture the bottom yellow arrow shows where the belt is vibrating, seems minor but the noise is horrible.

The top blue arrow shows the tensioner arm...I believe I need to remove the arm to be able to take the complete assembly off...have unscrewed the centre allen key at the back of the tensioner but the arm wont budge.

As said before the tensioner itself seems quiate although the arm does rise and fall as the belt clatters so I have to presume the spring has gone a bit weak?




 

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if you can lever the tensioner up and it springs back,i would assume its ok.Dont confuse a clatter with the age old 'vacuum pump clatter '(lots of info on here).To rule this out-start engine and pump brakes-if clatter goes away briefly-its your vacuum pump.hope this helps
 

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these type are prone to siezeing as said try to move it but normally need a new one as wd40 etc dont keep it free for long but do check your vac pump as very common on these tho belt may of stretched
 

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Discussion Starter #9
I've put a new belt on and plastic tensioner wheel & the clatter noise is 100% generated by extreme slapping of the belt between the bottom pulley & the water pump pulley, if I hold a finger (burns a bit!) against the belt between the pulleys it shuts up immediately.

Tensioner not sticking & has loads of return tension on it too but I can't think what else to try? I just desperately want to get the firking thing off & replace it to rule it out, but the arm prevents it from being removed & for the life of me I can't get the thing off?

Love to know how it seperates from the tensioner mech please
 

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Discussion Starter #10
Last optamistic bump before the weekend as i'd love to get this tensioner off tomorrow.


I'm sure it's dead simple but I don't want to damage it by smacking it to loosen it & find out after there is a specific way of getting the arm off of the spring unit.

Tried undoing the allen screw at the back which looks like the answer but it wont budge.
 

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Could it be that the water pump is seizing or slowing slightly causing the belt to 'flap' as one pulley slows and the other doesnt???This has been annoying me since i read your post.Let us know if you cured/solved it.
 

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Discussion Starter #13
Could it be that the water pump is seizing or slowing slightly causing the belt to 'flap' as one pulley slows and the other doesnt???This has been annoying me since i read your post.Let us know if you cured/solved it.
I've been thinking the same thing regarding the water pump, but it feels free just spinning it by hand but it is logical that this would cause the exact problem.

I slid another new belt on & it is much better, in fact once it's done a couple miles from cold it's nearly gone altogether.

I wonder if the water pump pulley is more resistant to turning with the belt fitted i.e under load? Bearings just starting to fail but not showing any play without the belt fitted?

MmmmmLOL:
 

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I too have a 2.4 D AAB engine and I am in the process of changing all my belts and have been advised that you should always change the water pump at the same time, cost around £30.

ChrisW
 

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Discussion Starter #15 (Edited)
My water pump was changed with the cam belts, think I'm having a senior moment & the pump (pictured page 1) to the right of the pulley is actually the power steering pump.

Age, drink & kids are my primary excuses, closely backed up by total incompetance.
 

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One thing I forget to say was I was also told that the belt is tensioned with the water pump ? as to how I am not sure but then I have not looked as I am getting it all done by someone else. Apprently alot of people make the mistake of ordering a tensioner for the AAB engines when in fact its not required.

ChrisW
 

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Discussion Starter #17 (Edited)
One thing I forget to say was I was also told that the belt is tensioned with the water pump ? as to how I am not sure but then I have not looked as I am getting it all done by someone else. Apprently alot of people make the mistake of ordering a tensioner for the AAB engines when in fact its not required.

ChrisW
The pic below is the tensioner, sprung loaded pulley wheel holding the ancillary belt in tension, pic taken from my bus & it's definately there ChrisT:

Arm is seized into the tensioner itself so its enjoying some WD40 at the moment until I get more persuasive with it the weekendI:
 

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I've got to do this job this week... have you got it apart?

Mine slaps when cold but goes away when you rev it.. I hope this is my noise..

i've spent £50 on a Tensioner, Wheel and Belt..

I assume the tensioner unbolts from the engine and then i can remove the arm from the tensioner?
 
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