Lotus Elan

S4 Sprint Alternator Conversion - Wiring assistance please?

PostPost by: l10tus » Thu Dec 29, 2011 11:00 pm

The Lucas LRA 101 Alternator is installed and mechanically complete.

I collected a wiring harness 'Jump Lead' set from Paul Matty, but this wasn't supplied with a wiring diagram,( I was told to look at the Workshop Manual, etc.).

I checked in Brian B's book. but didn't understand the written description, not having a diagram to refer to, especially with the references to Starter Solenoid connections ?

I then refered to the notes I'd received from Club Lotus, in the i-Tec Bulletin: Elan Series 4 Conversion to Alternator System. This seemed clearer, with the wiring diagram included, so:-

I removed the Lucus ? 90 voltage regulator as described ok, but then I started to get confused, having found two (2no.) Brown and Yellow wires attached, one of 'large' diameter, and one 'small'. Neither was described in the Bulletin as being large or small, or the cross sectional area confirmed.

The Bulletin dosn't really confirm clearly, which wire to use in connectiong to the altenator, or which one to 'Tape Back' - but I assume it's the smaller diameter one that connects to the small diameter cable from the alternator 'Jump lead?

Next issue: the 'Jump Lead has 3no. wires attached;-

1) 1 x Small 1.0sq.mm. Brown and Yellow with small male Lucar connector,
2) 1 x Large Brown and White (bare) and,
3) 1 x small brown with a 10mm, dia. circular connector.

But:- the i-Tech Bulletin describes only 2no. wires going to the Alternator ?

Next issue: The description in the i-Tec Bulletin of the wiring to the Alternator plug, shows the large 4.5 sq.mm. Brown and White wire in the centre connection of the plug (2 x large connectors and 1 x Small) but the jump lead is wired with the large Brown and White wire on the first connection ?
Does this have to be removed and repositioned in the centre connection on the plug ? and does the small brown wire get ditched also ?

I'm thinking that there may be a mix up in the description of installations between the earlier ACR Alternator and the later one with European termination, but that still dosn't explain the wiring position issues with the plug?

Any help would be appreciated, as there seems to be a few different descriptions on this topic, and I'm not sure how to really wire it.

Finally, I'd like to install a 60amp Ammeter at the same time - what are the connections for this and does it affect the Alternator wiring I'm planning?



UK '72 Sprint DHC

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