Accessory belt chirping badly, 306

TrinityJayOne

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Fellow Frogger
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Mar 19, 2011
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418
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Melbourne
A year or so ago my P/S pump went, had it replaced it with an aftermarket unit because that's all I could find. The mounting faces are different enough that the belt wasn't aligned right and jumped a groove, so had the guys at Alpine Affaire do their best to fix it. It worked for a while, or no groove skipping at least, but after a few months the belt started to chirp upon a cold start. Soon enough it got worse, chirping for longer and longer periods after starting, so I had AA take another look. Realignment via spacer shuffling and a new belt fixes it, but only for another few months. I've been through this process with them 2 or three times now while it's been in for a servicing. The last time I think they'd had enough, and they reckon it's currently as good as it's gonna get. Bugger.

Fast forward to today and the chirping has been back for a little while now (as AA said it probably would), to the point that it's doing it ALL the time rather than just when cold. The annoying part is that nothing ever LOOKS misaligned, but then I know it probably doesn't take much to cause this considering the small distances between some of the pulleys. Video for your perusal, mind the volume- https://youtu.be/MWz2Qvx_BkI

Q1- Any suggestions for a permanent fix? Preferably one that doesn't involve fitting a new accessory belt every few months!

Q2- How dangerous is continued operation in this state? Specifically, is the belt likely to overheat and/or weaken, then start falling apart? Or is it an annoying but ultimately fairly harmless issue?

All discussion/thoughts welcomed, cheers :)
 
I don't know the set up for the 306, but we had exactly the same symptoms in our Nissan Patrol. After changing the alternator, checking the AC compressor, the problem was, in fact, a stiff accessory belt tensioner articulation joint causing the belt to squeal on cold start -up. After disassembly and re-grease, voila! The chirp was gone for good.
 
Adding a touch of lubrication temporarily (WD40 spray to the ribbed side of the belt) can help determine if its tensioning issues, the slipping and noise would increase when lubed if the tensioner is not pulling enough, and would decrease if there is misalignment of the pulley.

Alignment only needs to be within a few mm and can be checked with a laser tool quickly:
https://www.youtube.com/watch?time_continue=168&v=xq6CUaH9rhc
Finally there are different belt profiles which claim to be advantageous for various applications, might be worth trying a different brand:
The Belts ? Continental
 
Lubrication makes the noise subside somewhat, but it quickly returns (the packaging of the area is rather tight and spraying large amounts is difficult). Also noticed that it gets worse once the engine is up to operating temp.

By the by, the tensioner and idler pulley were replaced when the P/S pump went in. Water pump was done with the timing belt < 1yr ago (and noise showed up before this anyway). Belt tension passes the highly scientific twist 90° w/ two fingers test.

Sigh...what a frustrating issue :x These days I don't have a nice level garage in which to jack things up, nor a body corporate/residents amenable to home grease monkey-ing-ery, otherwise I could put aside a weekend and throw some elbow grease at it myself :( I bet that laser device would sort it quick smart!
 
How about getting a second hand pug pump and refitting genuine?
 
A chirping belt means it is over tightened. Why is it over tightened is up to you to find out. As mentioned above, a tensioner that doesn't give can cause it. The fact that you replaced it doesn't mean anything. You need to check.

That said, are you sure it is the belt chirping and not a bearing? As in a tensioner bearing?
 
Definitely the belt and not a bearing, otherwise the noise would remain when the belt has been replaced 2 or 3x now.

How about getting a second hand pug pump and refitting genuine?

That was certainly my original plan! I only went aftermarket because of the 10~ 306 wrecks I checked, most engines had already been stripped down to the block if not removed entirely, and the few pumps I *did* find were in a pretty sad state due to the elements. I enquired with the usual suspects and was told about $500 to replace the pump, assuming they could find one (nobody sounded confident on that). Alas even if I got a pristine pump tomorrow, I fear I'd be in the same position unless it also had intact spacers & bolts etc.

Although the spacing on the aftermarket pump is different, I know for a fact that the pulley dimensions are bang on because it's the first thing I checked. No free play to speak of either and it spins smoothly. Just need to get the bugger in the right spot :mallet:
 
Alignment is going to do your head in, I have a spare here but now I have two cars with them its no longer a spare, it necessary backup.

I am sure there ill be good ones at wreckers, your lucky to be in Melb where there are lots of them, tried ASV? They do charge but might negotiate.
 
Figure it's time for an update on this!

Apparently the tensioner was weak and the P/S pulley was overly smooth, causing it to partially slip. Tensioner was replaced and the P/S pulley was scuffed up. Also, the belt was smaller than spec (vaguely recall mention of a smaller belt being fitted previously to try fixing the squeal). With a new (correct) belt fitted the P/S pulley was still slipping, but with the old (smaller) one it was ok, so that's what I have now. Haven't heard a peep out of it since. Remains to be seen if the smaller belt had/will again cause issues.
 
I’m pretty sure I have a good s/h 306 p/s pump in my spares - can check if you like? The car it came off had done about 120k km.

I was going to say the idler pulley or pulleys (my 306 has two). Ones on the tensioner and one fixed. But seems odd if they’ve been replaced.




Sent from my iPhone using Tapatalk
 
Yep, both replaced with the pump a year or so ago. I watched them come out of the packaging and go onto the car with my own eyes! Who knows if tensioner was just a dud or if it's been over-extended and failed that way as I hear they're fairly easy to break.

Cheers for the offer but you hold onto your pump for now :) I'm hoping I've seen the last of the issue now.
 
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