Drive Belts - 2.5 Diesel

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WestyK
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Drive Belts - 2.5 Diesel

Post by WestyK » Mon Sep 17, 2018 5:55 pm

Hi all

After some advice. I have a 2.5 Diesel that developed a little bit of a squeak at tick over that I was sure was from one of the belts. Probably the Air con as it got worse when switched on.
Plus to my knowledge they have never been changed or at least not for a long time so thought it was worth changing them anyway.

So I bought some form one of the normal on line suppliers but when they arrived they were not exactly the same. they were the toothed type V belt rather than smooth. I don't actually think that makes any difference so wasn't too worried.
When fitted I am sure that they were not exactly the same length either. :?

So I fitted them anyway and at first start up all good. Sounded much better, quieter than it had been for a while so was defiantly the problem.
Took it for a run but now at 2000rpm or over i get a whine so wondered if it was too tight so loosened them a bit and it helped a bit but not fully.
Seems to be coming from the alternator belts as Aircon on or off makes no difference. so could be alternator or water pump i guess.
Thought they may bed in a bit in so didn't worry too much but when I started up again a week later it was squeaking again (but worse) and whining even worse. the squeaking does stop once warm though

So Finally my questions. lol
Does this sound like its just an issue with the belts or have I now unearthed something else like water pump.
I wasn't over happy with the quality of the belts but that may have been me being picky.
Has anyone else ever had any issues with changing belts. Does quality cause issues.

They were not from our shop by the way.

Cheers
Ian
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Northern Bongolow
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Re: Drive Belts - 2.5 Diesel

Post by Northern Bongolow » Tue Sep 18, 2018 10:42 am

There's several causes for whining etc.
Are the pulleys clean, new belts can ride higher in the grove, the old belts run lower in the grove so a dust or road dirt line can form high in the groves.
The water pump bearings or the tensioner bearing, or even the Aircon pump all can fail or start to fail giving this noise.
The main crank pulley is a rubber bonded 2 piece pulley, this can separate, the outer spins at a different rate initially when cold then grips as it gets hot, it can spin when revved hard. Look for my thread in search on how to test and change if found to be faulty, it can be hard to examine and test so check carefully.
Spray each belt in turn with a little water to find out if it's belt related, then spray the tensioner with a service spray on the bearing see if that helps.
WestyK
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Re: Drive Belts - 2.5 Diesel

Post by WestyK » Wed Sep 19, 2018 9:02 am

Thanks for the pointers

I will do some more investigation at the weekend.

I was wondering if bet make or quality was ever an issue but seems not so will look at everything else before buying anymore

Ian
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mikeonb4c
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Re: Drive Belts - 2.5 Diesel

Post by mikeonb4c » Wed Sep 19, 2018 10:47 am

Northern Bongolow wrote: Tue Sep 18, 2018 10:42 am There's several causes for whining etc.
Are the pulleys clean, new belts can ride higher in the grove, the old belts run lower in the grove so a dust or road dirt line can form high in the groves.
The water pump bearings or the tensioner bearing, or even the Aircon pump all can fail or start to fail giving this noise.
The main crank pulley is a rubber bonded 2 piece pulley, this can separate, the outer spins at a different rate initially when cold then grips as it gets hot, it can spin when revved hard. Look for my thread in search on how to test and change if found to be faulty, it can be hard to examine and test so check carefully.
Spray each belt in turn with a little water to find out if it's belt related, then spray the tensioner with a service spray on the bearing see if that helps.
Interested in this Ady - could you recommend a good service spray. Also, did i recall a discussion many years back about some belts having the wrong vee profile and exerting excessive 'splitting' force on the crankshaft pulley faces, causing the pulley to fail as you described (note to OP - I'm not suggesting your new belts have that problem!)
teenmal
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Re: Drive Belts - 2.5 Diesel

Post by teenmal » Wed Sep 19, 2018 11:32 am

This is the proper belt for your vehicle, if it has been running with the wrong profile belt/s I would check the pullies for wear ( be careful they might have very sharp edges)This particular profile should stop any build up .Use a light machine oil spray on the idlers/tensioners etc.


http://semref.com/replacement/WL1115908 ... /GOODYEAR/
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