I have a new noise under the bonnet of late. Basically once the car is upto normal temperature a sound kicks in that's like a mix between a noisy computer fan and an electric motor loading up.....sort of a low frequency buzzing noise. It's only with engine running, sounds like it's coming from the waterpump / alternator / compressor area.

Water pump, fan and radiator are fairly new. It's not the tank / canister valve, nor does it appear to be the stepper motor. I have my doubts about it being the fuel pressure regulator but I'm going to investigate this further later.

The car is running fine, doesn't seen low on power or running any more rough than it normally might.

Anyone here know what an alternator sounds like with worn brushes, or anything else that could be making these sounds?

Thanks.

Thermo fan out of balance? Mud stuck to a blade, blade broken?

M

Good ideas there. Not thermofan as its not necessarily running at the time.
I do have one of those white 'blade-thrower' fans but its pretty new, so hadn't considered that one.

The fixed fan can still flex even when new. Double check yours by pushing the blades and checking if it fouls anything. I found mine fouled the rad cowling because the rubber mounts on the bottom were too thick. Changed them for thinner ones and fixed the issue.

Hooroo

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Rob Forsyth
Miniot!!

Just went outside for a poke around.
With car cool-warm there's no sound. If I move the radiator cowling with the car idling nothing touches. Fan has all its blades and doesn't appear to be rubbing.
As the car warms up the noise gradually gets louder. It's definitely something in that front quarter region.
Thinking I'll pull the alternator out and get an auto elec to put new bearings and brushes in it, and I'll put a new belt tensioner pulley in there too.

do you have one of these?

http://www.ebay.com.au/itm/Ry-Tools-Mec ... 23157e4ae9

really handy for finding wierd noises...

similar to putting a long screwdriver against your ear and probing around with the tip, but a whole lot better

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did I tell you that I won a trophy?

Might be useful that one.
Thanks.

long engineers screwdriver held to the ear gives the same result and a lot cheaper.

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I can tell you've never tried a proper stethoscope, because you'd know that it doesn't even come close!

besides, where do you get a long engineers screwdriver for $20

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did I tell you that I won a trophy?

Had the same issue when I had my SPI, it was the alternator (diagnosed with a screwdriver!). Changing it over fixed the issue, sounds like you are on the right track.

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1964 Morris "Cooper S" Group Nb Racer
1965 Morris 850
ex 1967 Morris Cooper S
ex 1969 Morris Van (Rover SPI running gear)