Alternator problems

[davidj]

Hi,

Started up my elan after the winter and the alternator light will not go out. Voltage between the soleniod and earth is 12.6v (battery voltage) with the engine not running and 12.2v with the engine running. All the earths are good. Belt tight and not slipping. Good connection on the pin connector at the rear of the alternator.

Anything else anyone can suggest before I pull out the unit and have to buy another one?

Ta,

David

[david.g.chapman]

Hmmm.

The alternator is unlikely to have failed during the winter, but it could either be that, or another connection is giving trouble. Check the thick brown wire going from the alternator to the battery via the ammeter and the starter solenoid, and also the other reference wire. If you disconnect each wire in turn you could substitute another wire to bridge the suspect connection to wherever each wire is going.

Also, as the alternator is easy to remove, just take it to an auto electrician and get it checked.

Dave Chapman

[paddy]

If the terminal voltage is 12.2 when the engine is running, then the alternator is not charging, which will make the light come on. If the light comes on, then I think it tells you that the reference wire is intact. As Dave says, you should also eliminate the ammeter (if you have one) as the cause by removing it from the circuit and connecting the terminals together directly.

Failing that, you say that the alternator connections and drive belt are ok so the problem is with the alternator unit itself. You might be able to get replacement brushes or a new voltage regulator but nowadays these seem to be harder to get so a replacement is by far the simplest option.

Some here will advise you to take the opportunity to junk the Lucas one and replace with a more reliable one.

Paddy

[bob_rich]

Hi David

There was another post recently about this and I made a comments that it could be sticky brushes on the slip rings. There were a lot of other useful pointers by other posters as well. As you say it has been stood 4 a long time it could be that the brushes R sticky--they R easy to check and fix

Info mine and others in the attached link

Hope this helps best of luck

Bob

elan-f15/igniton-light-showing-but-alternator-charging-fine-t22048.html

[davidj]

Hi,

Thanks for your comments; the brushes look OK os I have decided to put my hand in my pocket and buy a new one. However which one? Assuming I am sticking with a lucas unit, the manual says it is a 17ACR but the picture shows two plugs on the back, the large 3 pin and another two pin one. My car is wired with just the single 3 pin plug. The exiting unit is a remanufactured alternator with a "thoroughbred 64172" badge and no original Lucas markings.

I have discoved the LMA100 is a modern replacement for the 17ACR but again unsure if it has one or two plugs.

Thanks in advance for any help.

Cheers,

David

[paddy]

It looks like the standard 3-terminal connector to me:

http://www.ccw-tools.com/popuplargeimag ... Alternator.

Paddy

[davidj]

Hi,

Yes, this is very similar to the one I have. So does the original 17ACR only have one connection rather than 2 as per the Lotus +2 workshop manual ( page 95 section M)?

or, if I ask for a replacement for the 17ACR will I end up with the 2 plug version?

Cheers,

David