Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Alternator Wiring help?

Surely wasn't your car originally fitted with a voltmeter ? not an ammeter.

It seems the early Lucas 11ac alternator with its complicated external voltage regulation was fitted to Morgan's until at least 1984 according to various wiring diagrams. These models seemed to continue using ammeters although Land Rover (from which we can often draw parallels) when they offered this alternator switched to voltmeters in the late 60's as shown above.

I think Jack's assumption the ammeter is wired "through" the starter relay is a red herring. The battery side ammeter terminal (brown wires) is just used as convenient connection point for main power to relay which then triggers starter solenoid. No current flows through ammeter when starter is operated therefore.

Pretty sure my '76 did not have an external voltage regulator. Of course, as I was not the first or even 4th owner, a newer alternator may well have been fitted

My '75 doesn't have a separate regie .... same proviso though .... it's been about a while and may have been modded.

K

The more I think about it, I might just bypass the ammeter and connect the lead direct to the battery post on the solenoid. Will get maximum charge to the battery,and not risk any thermal issues with the ammeter wiring.

Makes sense electrically

The issue surrounding the wiring diagrams is that Morgan used the same wiring diagrams for a Plus 8 (which had an externally regulated alternator) and the 4/4 (which didn't)!

The Ford crossflow never used an externally regulated alternator.

Makes sense wiring it to the battery post on the solenoid.

On the crossflow rally cars we used a compact alternator from a Kubota, very light and powerful (60A to 95A) and cheap too - about 75 quid from the local Kubota dealers.

Arwyn

Thanks for all the help.

All wired up using flexi 16mm2 110AMP cable direct to solenoid. While I was fiddling I also finally got round to fitting a strip fuse on the main brown cable (as recommended!).

Although not properly connected, there appears to still be conectivity between the two posts on the ammeter so will leave 'as is' for the time being. If any problems,I'll piggy back both wires on the same post. I've capped off the old alternator wire but left it, in case I ever want to revert back.

Sorry to do this thread to death but just been given this link.

It contains this very clear pictorial diagram of a 1972 4/4 11AC alternator and ignition wiring.

In true Morgan style, mine is1972 but had an ACR alternator - only two wire and no Warning light relay/ Alternator Relay or Alternator Regulator.

The wiring diagram in my first post was for a 1973 4/4 and apart from the errant Brown wire is correct for mne. Mine is registed Dec 72 so they may have changed from AC to ACR towards the end of 1972,