Alternator replaced, now new noise

[Johnny2R]

Had the alternator replaced the other day, since when there has been a new noise coming from the engine. It's mildly annoying rather than seriously problematic, but I'm concerned it might indicate some other problem and I'd like to get it resolved, so I'm interested if people might have an idea as to what it could be, something I can go back to the garage with.

With the engine running, I hear from in front of the driver's position what I would describe as a faint mid-to-high pitch whirring sound, rather like an electric motor. When I press the clutch pedal, the pitch drops, so it's not directly related to engine speed as such. It's not to do with aircon (which I thought it might be, as the aircon gubbins had to be removed for the alternator replacement), inasmuch as it occurs with aircon turned off as well as on.

Any suggestions, anyone?

[grivas]

Had the alternator replaced the other day, since when there has been a new noise coming from the engine. It's mildly annoying rather than seriously problematic, but I'm concerned it might indicate some other problem and I'd like to get it resolved, so I'm interested if people might have an idea as to what it could be, something I can go back to the garage with.

With the engine running, I hear from in front of the driver's position what I would describe as a faint mid-to-high pitch whirring sound, rather like an electric motor. When I press the clutch pedal, the pitch drops, so it's not directly related to engine speed as such. It's not to do with aircon (which I thought it might be, as the aircon gubbins had to be removed for the alternator replacement), inasmuch as it occurs with aircon turned off as well as on.

Any suggestions, anyone?
Take it back and ask them to check the belts ALL the belts and tensioners are routed correctly and not too tight. Ask them to explain exactly what was done speak to the actual chap who did the work.

[Johnny2R]

I'm certainly going to take it back. I'd just like to help them target the likely problem (I don't want more problems to occur as a result of fixing this one). Could the noise be a result of incorrect belt tension somewhere?

[klarzy]

if it drops when you press the clutch its not the clutch slave bearing starting to wear and just coincidence??

[Johnny2R]

if it drops when you press the clutch its not the clutch slave bearing starting to wear and just coincidence??

Well, it might be, but it started immediately after the work done the other day. Definitely inclined to suspect something specific to the work done.

[COLVERT]

Was it a new alternator or a re-con ?

Could be the alternator front ball race.

[Johnny2R]

Was it a new alternator or a re-con ?

Could be the alternator front ball race.

It was a new alternator.

[COLVERT]

It looks as though the belts or pulleys are the problem then as the noise started after you had the alternator fitted.

[Johnny2R]

The garage where I had the alternator replaced have not been able to fix this problem, which they identified as coming from some 'jockey wheel', which they lubricated (without any effect). So I want to take it elsewhere and have someone else look at it now. How Rover-specific an issue is this likely to be? Or is it something any competent garage without Rover knowledge and experience should be able to sort out easily enough?

[klarzy]

I have a bearing noise on acceleration on mine now i have changed the alternator.... i may try a new belt and tensioner bearing...

[Johnny2R]

I have a bearing noise on acceleration on mine now i have changed the alternator.... i may try a new belt and tensioner bearing...

What does this mean? It sounds very relevant to my situation. I was with Phil-T4 today and he was convinced the noise in question was coming from the alternator itself. The garage claim to have checked the alternator out (not sure how). But it certainly did sound to me like possible bearing noise from the alternator (Phil held the point of a long screwdriver against the body and got me to put my ear to the other end).

[klarzy]

What does this mean? It sounds very relevant to my situation. I was with Phil-T4 today and he was convinced the noise in question was coming from the alternator itself. The garage claim to have checked the alternator out (not sure how). But it certainly did sound to me like possible bearing noise from the alternator (Phil held the point of a long screwdriver against the body and got me to put my ear to the other end).

what it says bud... the noise may be coming from the belt tensioner bearing, when a belt has been running in place for a long time and you disturb it by say, changing the alternator and putting the belt back on, then the bearing may have subtly changed it's load and does not like it... when I changed mine I did notice a tiny amount of play in the bearing...

[Johnny2R]

what it says bud... the noise may be coming from the belt tensioner bearing, when a belt has been running in place for a long time and you disturb it by say, changing the alternator and putting the belt back on, then the bearing may have subtly changed it's load and does not like it... when I changed mine I did notice a tiny amount of play in the bearing...

So I should get someone to look at the belt tensioner bearing? Just trying to point someone in the right direction.

[Phil-T4]

The noise is most definitely coming from the alternator, even before i got my ear to the screwdriver stethoscope i could hear it screaming!

[Johnny2R]

Is the belt tensioner bearing separate from the alternator, then? I am clueless, please treat me gently!

[Mike Noc]

Yes it is. The tensioner is automatic so there is no adjustment.

As Phil has identified the source of the noise, best to take it back to the garage that fitted the alternator and demand they replace it.














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[Dallas]

John, have you managed to get to the bottom of the problem?

Do you get the noise as soon as you start the car, or does the noise start after 5 minutes of engine running?

[maxi_crawf]

Just over a year ago the Alternator on my 75 failed, it was replaced with with a service exchange one, after about 3 weeks I had the same symptoms as you describe so took it back, it turned out that it was on the point of failing also, it was replaced under warranty no questions asked so it could be that your "new" one is on the way out, sometimes it happens :shrug:

[wizzo337]

Hi.
Whenever I used to get noises on my Mini. The one designed by Sir Issac, not one of those new fangled BMW fakes. I used to get a length of thin tubing, stick one end in my ear and then poke the other end round where I thought the noise was coming from. You will soon be able to pinpoint anything unusual as it does get very loud when you are in the right area.

Wizo337

[Mike Noc]

I used to do the same as Phil with a screwdriver, but up the car boot one day I noticed a genuine doctor's stethoscope and bought it for three quid.

Bargain for such a high quality bit of kit. :D

[Dallas]

My ZT 2.5 engine starts and sounds perfect, but after 7 minutes (yes I timed it), I get a slight whirring noise, sounds as something is dry.

Leave it running and it can fade away, but not fully, can always hear it.

The noise does not change pitch with acceleration.

[DMGRS]

Sounds like it could be the same issue - time to find a big screwdriver or similar, and use it as a stethoscope. :)
It's a handy trick, and has saved me replacing all sorts in the past. Just be very careful to keep it away from moving belts etc.

[Dallas]

Sounds like it could be the same issue - time to find a big screwdriver or similar, and use it as a stethoscope. :)
It's a handy trick, and has saved me replacing all sorts in the past. Just be very careful to keep it away from moving belts etc.

THIS (https://www.youtube.com/watch?v=UUiDQowIa20) is what minds sounds like. :eek: