Fan Belt Squeel...

[Raeman]

Hi all, just recently been having a very loud and annoying squeel coming (I think) from the fan belt.

It only does it when the car is cold, so first thing in mornings or when it's been left for a while.

It also does it when the heaters or Air-con is used to help clear a misty screen or condensation in the car.

Just need to know if anyone else has had this issue and can tell me for sure that it is the fanbelt at fault, as there appears to be two belts fitted.

Also, how tricky a job is it to do yourself? Any special tools needed? Simple or garage job?

Thanks. ;)

[Cherry Red Pocket Rocket]

I heard a squeaking in my old Honda. Took it into a garage, they tightened up one of the belts, quick easy job (if you know what you're doing and have the right tools) and didn't even charge me for it! Try and identify the problem first, look it up online or get a Haynes manual and failing that, take it into a respectable garage and ask them to tighten up the belts for you. Shouldn't cost much if anything at all.

[Chris81]

Carefully squirt a bit of WD40 over each of the 2 auxilliary drivebelts and you'll soon diagnose which one it is. People will doubtless say don't spray WD40 over the belts but a little really doesn't hurt. Lots of cars aux drivebelts squeak at idle when they're cold or there's dampness in the air. I'm sure after about 5 minutes of driving it'll wear off as the belt warms up. As long as the belts are in good condition and correctly tensioned then I don't see it as a problem.

[alfiejts]

Like Chris predicted, I'm wincing at the suggestion of using WD40 as any oil based lubricant will cause damage to the rubber of the belt and could lead to premature failure.

I suspect that like Chris says, using a little won't have that much impact but I wouldn't want to try it.

I went out and bought a "proper" belt conditioner aerosol from a car accessory shop, that was designed to eliminate the squeaking of the rubber without potentially causing slippage or rubber damage.

Be aware that the squeaking noise is the belt slipping, which really means that its not properly tensioned. Any "lubricant" such as WD40 will actually make the slipping worse (even if it silences it in the process) and that might overheat the rubber belt and cause failure.

If the belt isn't tensioned enough, slippage is worse in cold weather as you get damp on the pulleys and also the load on the alternator is heavier with all the extra electrical equipment running (fans, lights, etc) making it harder for the belt to turn.

Best bet is to live with it until the car is next being serviced and then to make sure that they check & retension the belt.

[sisaven]

Another possible source of the "Squeal" could be Idler Bearings, or Water-pump Bearings.

if you have checked the Tension of the Belt and this is OK (a fairly tight belt on the Yaris) and there is no evidence of cracking, of frayed canvas showing through,or heavy "Glazing" on the smooth side of the belt, - then Bearing failure is a strong contender.

Not a good DIY job, for the average non experienced mechanic, due to the Hard to get at positioning of both components.

Good Luck.

[in_the_no]

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[Raeman]

Another possible source of the "Squeal" could be Idler Bearings, or Water-pump Bearings.

if you have checked the Tension of the Belt and this is OK (a fairly tight belt on the Yaris) and there is no evidence of cracking, of frayed canvas showing through,or heavy "Glazing" on the smooth side of the belt, - then Bearing failure is a strong contender.

Not a good DIY job, for the average non experienced mechanic, due to the Hard to get at positioning of both components.

Good Luck.

Thanks for that info sisaven, just today i checked it properly and the belt driving the alternator is quite loose. Well when i say loose, in the middle of the belt there is about 1 and half inch play in it. :(

When you run the engine and look at the belt it looks quite slack but then seems to go tight as you rev the engine.

It's also quite glazed and maybe just needs replacing so the other belt will have to be done aswell i guess.

Any idea how big a job this is, i mean how long would it take to do and what kind of cost would i expect from a decent garage,non toyota dealer?

Thanks. ;)

[sisaven]

Another possible source of the "Squeal" could be Idler Bearings, or Water-pump Bearings.

if you have checked the Tension of the Belt and this is OK (a fairly tight belt on the Yaris) and there is no evidence of cracking, of frayed canvas showing through,or heavy "Glazing" on the smooth side of the belt, - then Bearing failure is a strong contender.

Not a good DIY job, for the average non experienced mechanic, due to the Hard to get at positioning of both components.

Good Luck.

Thanks for that info sisaven, just today i checked it properly and the belt driving the alternator is quite loose. Well when i say loose, in the middle of the belt there is about 1 and half inch play in it. :(

When you run the engine and look at the belt it looks quite slack but then seems to go tight as you rev the engine.

It's also quite glazed and maybe just needs replacing so the other belt will have to be done aswell i guess.

Any idea how big a job this is, i mean how long would it take to do and what kind of cost would i expect from a decent garage,non toyota dealer?

Thanks. ;)

I would suggest that before you Change the Belt, you should inspect it for any signs of damage bad cracks, fraying, etc. if OK, and you can get you hands on the belt, you can remove the "Glazing" with a light rub over the back of the belt with fine wet or dry paper. NOT WITH THE ENGINE RUNNING (I'm not sure of the run of this belt on a MK1 Yaris and assume the "Back" of the Belt is a Drive Surface)

Then adjust the Belt to the Correct Tension, By slackening of the adjustment nuts on the Alternator, and re tightening, when correct tension is attained. I haven't the Tech Specs for a MK1 Yaris, but I would suggest a tension of 1cm up or down at its longest point. or to Toyota spec. which you should find in your Hand Book. the 1.5 inches that you have at the present time will produce a Slipping Belt

If you do intend to Change the Belt, due to high mileage and bad deterioration, I would go to a Motor-factors that stock "Gates" Brand Belts as these in my opinion are the Best.

I have not personally changed an Auxiliary Belt on a Mk1 Yaris, I did change the Belt on my MK1 Avensis, - not easy - very title space to run the Belt over the pulleys, had to have an assistant to hold back Tensioner when I ran belt around, with help of a mirror. but it should be a lot easier on the Yaris as the Tension is fully adjustable with the alternator, and there are fewer pulleys to negotiate.

Hope this is of some Help, Good Luck.

[Raeman]

Ok mate thanks for the info. ;)

Your quite right about there being very little room to work with, it's very awkward to get to the belts.

I'll check it fully for any serious wear and adjust it. If it won't tighten properly i may run it down to a local garage i know, they are experienced and decent types so i trust them and it shouldn't cost much if i buy the belts myself.

Thanks to in_the_no aswell for help on how to tighten the thing. ;)

Cheers. :)

Edit...Just out of curiosity, what would happen if the belt snapped? Would it lunch the engine or be ok? :(

[in_the_no]

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