Can you help me identify this alternator

[tvacc]

Hi all,

My Elan was built by the Spyder guys back in the early 80's. The alternator is making a grinding and clunking noise. Can you help me identify it? it is a Lucas. Pictures below. I will add two more in a few minutes.

Edit.Waiting for the pics to email from my phone...looking on the web I see Lucas #10425 12038. Look the same but do not know the difference. Can someone tell me how to identify these? I dont see any numbers.

[billwill]

The cogged pulley is a non-standard modification, make sure that you take that off to fit on a new alternator.

[billwill]

I think the usual one that gets fitted to our twin cams is a Lucas 17ACR so it is probably one of those.
Take a look at these images and compare them with your alternator.

https://www.google.com/search?client=ub ... tf-8&gl=uk

http://trf.zeni.net/TR6greenbook/11.php ... 0&s_ht=744

17ACRs have a max output of about 35 amps. If you have a lot of electric addons consider an 18ACR which has a 45 amp max output.

[billwill]

If I blow an alternator, which I have had happen once or twice, I just take it off and take it to almost any local motor factors and get an exchange re-built unit; it's a common motoring part. That way I can be sure to get the correct orientation, i.e one set for mounting on the left side of the engine.

I understand that a wrongly handed one can be converted by undoing the long bolts ant rotating the front section of the alternator, but I've never done that myself.

[pharriso]

So do you have a toothed crank pulley & water pump pulley?

[tvacc]

So do you have a toothed crank pulley & water pump pulley?

Yes

[sutol45]

Lucas ACR17 36amp machine with a toothed drive pulley.

The standard pulley supplied by Lucas would have been for a V-belt, as shown:

[tvacc]

OK, I think we know it is a 17 or 18 ACR,

now, where do I get one in the USA?

[sutol45]

OK, I think we know it is a 17 or 18 ACR,

now, where do I get one in the USA?

Tony, give over!

You do not need an 18 ACR on an Elan - even if you do have a heated rear screen...

As for where you get one in the US...

[tvacc]

OK, I think we know it is a 17 or 18 ACR,

now, where do I get one in the USA?

Tony, give over!

You do not need an 18 ACR on an Elan - even if you do have a heated rear screen...

As for where you get one in the US...

Ok, I found one a Moss Motors on the advice of Jeff at JAE. I took mine this morning to a local rebuilder. We will see what he can do with it. He is going to replace the bearings and test it. It was making a rumbling noise on rev up. I put a broom handle to it and could very loudly hear the sound, like a bunch of nails rumbling inside a can. I put the broom handle on the motor right off the back of the alternator and no loud sounds there. When I spun the pulley, it seemed all right to me and the repair guy. We shall see what he says later today. I can get the one from Moss in 2 days.

[billwill]

On your photo, your rear securing bolts for the alternator looks as if it is rigidly tightened.to the alloy casting.

Your Alternator( indicating rear bolt)

I do not think this is advisable, as the temperatures increase the alternator will expand a little and will expand more than the steel securing bracket, this could put extreme pressure on the rear casting of the alternator and could crack it.

The rear mount should probably be like the one on my car. It is basically a sleeve which is just a tiny amount smaller than the hole in the alternator rear casting. The sleeve is bolted rigidly to the bracket, but the rear casting of the alternator can slide (just a tiny tiny amount) to and fro on the sleeve as the temperature of the alternator varies.

I suppose you could use two rubber washers instead, one on each side of the rear casting of the alternator, but you also need to ensure that the diameter of the bolt is a close fit to the hole in the alloy casting, to prevent lateral vibration.

[tvacc]

Ok, will look at that. It has been on the car for about 33 years bolted just that way. I will look for sleeves.

[Galwaylotus]

If I knew a motor rewind shop locally, I'd just get it rebuilt.