Belt squeal diagnosis

[chris_dono]

Hey all,
I've had a look through the various threads about belt and pulley noises on here, but I can't seem to find one that's the same as mine, sorry if i've not found it yet !

When i start the car up from cold, I get a really loud screech/squeal/whatever you want to call it from either a belt or a pulley, but I'm not sure exactly where it's from.

It goes away after a few seconds, but until the car is warm, it'll come back when i pull away, and sometimes if i have the aircon on it'll start again, but go once i let off the throttle.

How would i go about working out which belt/pulley it is ?

Thanks
Chris

[Amonlym]

you could try removing the PAS/AC belt from the equation (loosen the tensioner from below, big pulley at the bottom front) - this would eliminate that belt entirely allowing you to focus on alternator, alternator tensioner/idler and main drive pulley.
From what i understand
- squealing just after start-up is normally alternator
- AC related squealing is normally from the PAS/AC belt
- AC related squealing could be replicated by loading up the power steering also
- The drive pulley on the engine itself is prone to separating which might sound the same as either or both of these (edit: Refer this thread https://www.clubvr4.com/forum/showth...t=crank+pulley)

I would be tempted to think you have AC belt that sounds on the AC as described, and on the PS when pulling away (as this often also involves cornering).

Replacing the belts is not expensive and can be done on a driveway, the only difficulty is having a spanner that will get onto the alternator idler pulley to loosen it so the tensioner can be moved (combined, the pulley locks the tensioner in place) - this faces directly into the strut tower, so a offset spanner is basically essential.

[Nick Mann]

https://www.clubvr4.com/forum/showth...lternator-belt



It could be either of the accessory belts - if they are old, change them. If they are young then re-tension them - you are looking for a cm or so deflection when you give the long side a reasonable push.

[chris_dono]

Thanks guys, I'll take a look and see what I can work out !

[Erni902]

I have this on my 350Z. Its a brand new alternator belt that is the culprit and re-tensioning it tends to sort it out. It was really bad when it was first put on but has got better, apparently the Zed is a pig to get the right tension as it has to be bang on. Its also a b@stard to get to to tighten up so until it gets worse I wont worry about it.