ZD30 Belt Squeal

[Rosco99]

Hey Guys,

Recently had the belt start to squeal due to excessive wear and had it replaced by an ARB mechanic. A Dayco belt was used for the replacement and I was assured that it was "the same as a genuine belt". Following this after <1000kms the belt squeal came back. I took the car back to the mechanic who said it was the belt tensioner that needed replacement. As I am short on cash I did it myself with a new genuine tensioner. Imagine my shock when I turned the car on with the new dayco belt and genuine belt tensioner in there and the fkn squeal was still present at idle...

I used a spray bottle and wet the belt at the alternator pulley and the noise stopped immediately, yet came back within a few seconds. Now I know its not likely a bearing problem because none of the pulleys had any play and were very firm, and the water stopping the noise leads me to think misalignment or shit belt.

I am thinking it would be a good idea to get a genuine nissan belt and chuck that on, see if that stops the squeal and if it doesnt have a closer look at the alternator.

[the evil twin]

FWIW I have never had any success with aftermarket belts on ZD30.
Same as belt lube or soap or whatever, the squeal comes back pretty quickly
Genuine belt seems to stop the squeal every time tho.
That is given that the issue was indeed the belt and not the Tensioner/Alternator clutch/ AC pulley.

The above is a pretty common finding by a fair few others on the forum as well

[Sir Roofy]

Sounds like a plan

[LostBenji]

Got an A/M sucker on mine, no issues. Might need to investigate why the squeal rather than treat the symptom.

Rosco, do you have a dual battery system or if single, are you draining it too much?

I have seen this before with too much load on the alternator thanks to stupid/dumb dual battery setups that connect both batteries to the poor alternator at same time. Also get same issue if the alternator is bad and has shorted windings or diodes.

[the evil twin]

Got an A/M sucker on mine, no issues. Might need to investigate why the squeal rather than treat the symptom.

Rosco, do you have a dual battery system or if single, are you draining it too much?

I have seen this before with too much load on the alternator thanks to stupid/dumb dual battery setups that connect both batteries to the poor alternator at same time. Also get same issue if the alternator is bad and has shorted windings or diodes.

Not saying that won't happen but usually it is because of insufficient belt tension due to a siezed tensioner so the new tensioner should have sorted that out.

95% of electronic dual battery systems (100% of the non-programmable VSR based ones) will connect both batteries within moments of engine start anyway.

The Alternator whining like a Dog with its 'nads caught in a rabbit trap and/or the Alt warning light should give the OP a heads up if it is overloaded or faulty.

Given that the OP didn't mention 'only at night with headlights on' or somesuch then the issue appears to be there no matter the Alt load,
but...
A quick listen and a check of the Alternator idle voltage with minimal load IE no lights etc and then again with main beams, spotties etc all on and A/C fan on full will help ID or rule out that as a cause

[Rosco99]

Got an A/M sucker on mine, no issues. Might need to investigate why the squeal rather than treat the symptom.

Rosco, do you have a dual battery system or if single, are you draining it too much?


Single battery, nearly everything off, no lights etc. Will do the check the evil twin described anyway for good measure.

Gonna put a genuine belt in on Wednesday if I get a chance and hope that fixes it.

EDIT: Put a new belt on and its whisper quiet.. what a joke!