Lotus Elan


PostPost by: s28ven » Sat Jan 25, 2020 7:24 pm

Firstly, thanks for everyone’s help thus far. As some of you may have read I had a pretty bad experience with a local classic restoration garage and I am slowly (due to young family) working through the items they completed on the car.

I am now looking at the alternator and cannot fathom why they have left the old voltage regulator in place. I have only managed to start the car once since having it back and quickly tested the voltage across the battery while at idle as being around 12.5v. Meaning it’s not charging.

My understanding of the old voltage regulator is pretty basic so looking for some guidance. Is there any reason to leave it in place?

Is it wired correctly as per the below picture?

Thanks Again, Steven

37B4505F-B855-44E3-B76F-02063B44D6C8.jpeg and

5EB25C59-6A16-44CA-B89D-FDEB73D204A7.jpeg and
Second Gear
Second Gear
Posts: 70
Joined: 30 Sep 2014
Location: Glasgow

PostPost by: 1owner69Elan » Sat Jan 25, 2020 7:55 pm

You might find these instructions useful:
Dave Bean Alternator Instructions.jpeg and

Dave Bean Alternator Instructions 1.jpeg and
'69 Elan S4 SE
Street 181 BHP
Original owner
Fourth Gear
Fourth Gear
Posts: 779
Joined: 16 Jun 2015
Location: Napa, California

PostPost by: gjz30075 » Sat Jan 25, 2020 9:21 pm

Is that a Lucas alternator? Maybe it requires an external voltage regulator?? I've only installed Japanese
alternators which have their own internal regulator, which I leave in place for show. If its a Japanese
alternator, or any alternator with an internal regulator, then 1owner's posted instructions will work.
Greg Z
45/0243K Sprint
36/5727 pre airflow coupe
User avatar
Coveted Fifth Gear
Coveted Fifth Gear
Posts: 2950
Joined: 12 Sep 2003
Location: Roswell, Georgia, USA

PostPost by: nmauduit » Mon Jan 27, 2020 9:30 am

s28ven wrote:Is there any reason to leave it in place?

I have replaced the dynamo with a Lucas ACR17 but kept the original regulator in place for looks and reversibility, using it as a connection box as per D Bean instructions mentioned above (do not forget what to disconnect) : an alternator is relatively easy to connect (mostly 1 regulated current which is the thick wire, one warning wire and ground), just take your time to check and double check, then watch it at work with caution at first (quick cut off and disconnect if need be, check that nothing overheats wires or components, check that voltage at the charge behaves like expected which is going slightly up when revving as charging gets on...)
S4SE 36/8198
User avatar
Coveted Fifth Gear
Coveted Fifth Gear
Posts: 1469
Joined: 02 Sep 2013
Location: France

Total Online:

Users browsing this forum: No registered users and 3 guests