Noisy alternator
Noisy alternator
Author
Discussion

Litcoat

Original Poster:

143 posts

119 months

Friday 1st June 2018
quotequote all
Alright all,
Out for a spin tonight when all of a sudden the alternator started whining like hell, no battery light came on and everything else kept working., does this mean it's on its way out or have things got a bit dry with all this hot dry weather.

Cheers Mark

Belle427

11,205 posts

255 months

Saturday 2nd June 2018
quotequote all
It could be electrical noise which is usually a diode starting to pack in.
If your battery is fully charged, connections are are good and the belt looks ok then I would think it was that.
You could drop the belt off and see how the bearings sound, all be it with no load but you may hear something.

Steve_D

13,801 posts

280 months

Saturday 2nd June 2018
quotequote all
Is it a serp engine?
Are you sure it is not the tension/idle pulley bearing?

Steve

carsy

3,019 posts

187 months

Saturday 2nd June 2018
quotequote all
Can I just jump on this one if I may. Sorry op.

Just acquired what I was told was a brand new serp alternator, foc so can’t complain. Certainly looks brand new.

Charges fine but has a slight whine with it. Only noticeable on tick over. It’s there all the time hot cold and after a good run.

The other thing it has done a couple of times is that when hot after a good run. If I just switch the ignition on but not start the engine the ignition warning light flickers and my electric power steering pump bursts into life. The pump is wired onto the connection on the back of the alternator that should only be live when it is turning. When this occurs this is obviously getting power when it shouldn’t.

Whine is all the time this ignition light flickering with just ignition on is only occasionally,

Any ideas what needs replacing.

Belle427

11,205 posts

255 months

Saturday 2nd June 2018
quotequote all
I had a second hand one from eBay that made a whining noise when stationary and the ignition was off. It flattened the battery in 48 hours so I put 2+2 together and assumed one of the diodes had become faulty.
If all connections are identical I can’t really see it being anything else.

Litcoat

Original Poster:

143 posts

119 months

Saturday 2nd June 2018
quotequote all
Alright all,
Been back out checking the source of the noise, definitely the alternator, is there a good place to get a replacement or are they just a standard Rover item? I've got a few numbers off it, DMA 72 then 20090203 and finally 5332xx 53, where I've put the x' s the numbers have rubbed off, is one of these the part number?
Always appreciate the help,

Cheers Mark

Belle427

11,205 posts

255 months

Saturday 2nd June 2018
quotequote all
Have a search around for a company that refurbs them, may be a cheaper fix as a new quality item is over £100.

2gins

2,857 posts

184 months

Saturday 2nd June 2018
quotequote all
If that's the new price then a cost effective fix must be completed in under an hour. Credible?

Belle427

11,205 posts

255 months

Sunday 3rd June 2018
quotequote all
This has the info for the alternator, although your part numbers do look different.
I bought one recently for £111 but they seem to be out of stock at the moment.

https://www.pistonheads.com/gassing/topic.asp?t=16...

Litcoat

Original Poster:

143 posts

119 months

Sunday 3rd June 2018
quotequote all
I just went on tvr car parts and they are £120 , I'll give them a call to confirm the correct unit

QBee

22,065 posts

166 months

Sunday 3rd June 2018
quotequote all
What year is your car?

Litcoat

Original Poster:

143 posts

119 months

Sunday 3rd June 2018
quotequote all
She's a 98 400

Sardonicus

19,295 posts

243 months

QBee

22,065 posts

166 months

Sunday 3rd June 2018
quotequote all
It’s a Landrover alternator. I bought mine from Hobson Industries, who take new ones of LandRovers they upgrade for the military

Litcoat

Original Poster:

143 posts

119 months

Sunday 10th June 2018
quotequote all
Alright all,
Thanks for the help, new alternator fitted and the noise has gone, that bottom mounting bolt was a pig, had to hold the nut with one of those extending magnetic pens, handy little tool pleased I had one.

Cheers Mark

QBee

22,065 posts

166 months

Sunday 10th June 2018
quotequote all
Well done - nice colour by the way - we both have excellent taste


ChimpOnGas

9,637 posts

201 months

Sunday 10th June 2018
quotequote all
https://www.ebay.co.uk/itm/BRAND-NEW-Denso-Alterna...

This is the real deal 100a Denso for £115 including VAT & delivery direct from Denso UK themselves.

Litcoat

Original Poster:

143 posts

119 months

Monday 11th June 2018
quotequote all
That's the one I got, DAN020