Timing belt howling at low revs

[RT104GT]

Hi
I just refitted a new timing belt and idler pulleys to my 3SFE.
At low revs it wows and howls its head off quite loud.
I eased off tension but its still noisy as hell.
Its an after-market not original so I guess the match between the cogged pulleys and the belt is off a bit.
I also did the water pump again aftermarket try to save money.

I think its the water pump thats resonating.
It goes away with revs.
Anyone got any ideas, or I just let it run in.
Worse case is it will break but it won't damage the valves and I will have to fit another.
Is there any spray grease or silicon spray I can put on the teeth?
Belts are relatively inert but you are not supposed to lubricate then back or front as they could jump a cog.
Silicon grease is quite a good lubricant.
I am told chemicals are out and yet the dodgey bothers here tell me they do it all the time to timing belts.

Thanks for lookin

[horse]

hey steve, is the howling from the belt or idler pulley bearing? try taking off the other ancillary belts and see if the noise persists.

Cheers

[maurice c]

I couldn't recommend putting anything on your timing belt, it will damage it. Take the side cover off again and inspect it to see if its fouling anywhere on the timing belt. Take off the belt and see how the pump sound when you move it(I"ve had plenty of problems there), check each tensioner bearing as well as these usually need replacing when you change the belt.

[kriso]

definatley dont put any lubricants on the timing belt, i reckon your conclusion of being the waterpump sounds like the problem to me.

[DrNick]

If its not one of the pulleys then it could be a touch out of alignment. My memory is a bit hazy as its long since ive seen one, but on the 5S ( and I could expect similar setup on the 3S) there is a little metal plate which goes on to the crank after the timing gear. Its slightly curved and if you put it on the wrong way around the belt might start to slip off the pulley.
Just a wild stab in the dark though mate, the only other stuff I can think of is the usual pulleys and idlers that people have already mentioned above.

[litldv8]

is the belt to tight? they tend to "sing" if they are
neil

should read it properly first i see you have already done that

[pandaah]

Sounds like its too tight mate, did you lever the tensioner when you did it up? Loosen it off, turn the motor to compression then tighten it up, that way it tightens itself up to a safe enough tension

[pandaah]

by the way did you notice they make round tooth and square teeth belts? Make sure you have the correct belt

[RT104GT]

Sounds like its too tight mate, did you lever the tensioner when you did it up? Loosen it off, turn the motor to compression then tighten it up, that way it tightens itself up to a safe enough tension

All fixed

Took the top engine mount out and the p/s pump reservoir was moved out of the way and I then
prised the rubber grommet out so I could see the idler securing bolt.
I then released the bolt on the idler pulley and turned the engine over using the Alternator bolt and a 10mm ratchet spanner in a clockwise direction one full turn of the crankshaft until hard to turn on a compression stroke.
Nipped up the bolt then started and ran the engine and noticed after fans started when coolant was 80C the belt howling noise at really low revs (800) was slightly there, so I stopped engine and unbolted idler bolt again until loose and turned engine over 360 degrees again clockwise over two compression strokes and locked the bolt again.

Did bolt up tight and ran again, noise level down many dBA.

Put it all back together, didnt have to even take the top cover off.

QED

Thanks All

[RT104GT]

hey steve, is the howling from the belt or idler pulley bearing? try taking off the other ancillary belts and see if the noise persists.

Cheers

Hey Huy it was the belt.

Hows things

Just dumped who heap of VZv21 at scrap yard, maybe I shuda called u first?

[troysota]

As far as lubricants go it should be safe to use Teflon Spray.
I reccomend the new Forch Teflon Dry Lube.
PM me on how to get hold of it!

[allencr]

All fixed
...ran the engine and noticed after fans started when coolant was 80C the belt howling noise at really low revs (800) was slightly there, so I stopped engine and unbolted idler bolt again until loose and turned engine over 360 degrees again clockwise over two compression strokes and locked the bolt again.

Did bolt up tight and ran again, noise level down many dBA.

Put it all back together, didnt have to even take the top cover off.

It wasn't the belt, a belt wouldn't make noise only after it got to 80C because it's not affected by coolant temp and a belt wouldn't make noise only at low RPMs without also getting much louder at higher RPMs.
Also, I don't think you will find that tightening method of yours in any manual, factory or even the WWW, and very surprised that turning it over with the idler loose didn't skip any teeth.
I don't know what it was and I'm glad it's quiet now, but it wasn't the belt and/or its tension.

[TERRA Operative]

It's written in the 5EFE manual for one, except it's two revolutions.