this forum has helped me previously and i hope you all can come through again. There is so much knowledge available here.
I have an early 62 e, with positive ground. i have added a positive ground electronic ignition system, and it works fantastic. It was an accuspark by the way.
i have since recently decided to change out my old c42 generator with a new positive ground alternator. i had some failed regulators and decided to change out. I check the wiring to ensure i had no faults, continuity on all the wires and no grounds. I installed the new alternator, rewired as instructions stated. it had very poor instructions and only indicated that the field terminal go to the battery. My cars diagram shows most connections going to that same terminal at the " b" terminal of the voltage regulator, and in parallel, the solenoid negative side of the battery as well. After rewiring, only using old regulator as a terminal strip for " b" connections, i started the car, and got 14.2 volts at battery indicating positive charging. The warning light went out as soon as it started charging as usual. By the way, its a self exciting alternator. However when i look at alternator, it reads only discharge since no power flows through it as i can tell. Formerly the field from generator fed the G terminal on regulator. Now it feeds the B. Im thinking that this will bypass the ammeter from the charging side and only indicate the discharge as the fan or lights operate. Is this correct? or is there a way to wire it where it still gets current through the meter? I know that there are many of you out there that have changed to alternators. Seems simple, but it hasn't proved to be yet. Any information would help. I have looked for the alternator forums and haven't seen this problem as yet. Thanks in advance.

 

Hello from KC. Recently installed the alternator-in-a-generator conversion and finding the same issue. Ammeter shows a slight discharge when driving and that's with the aftermarket turbine fan running. Hit the brakes or turn signals and the ammeter pops over to additional discharge reading.

After 1/2 hour of break-in driving on my fresh engine, I checked the battery and it shows full charge. I'm guessing it's charging ok but ammeter won't confirm it. Double checked wiring instructions and everything should be correct. I have a voltmeter of its' way from Nisonger (matches other Smiths gauges). Hope this will resolve the issue. By the way, the original Lucas ammeter is rated at 25 or 30 (?) amps. My new alternator puts out 45 so 50 amp rated voltmeter should prevent possible problems.

By the way, Jaguar concours/All British gathering Sat, June 11 at Crown Center in KC. Should be great show. Will be showing my E.

Bob G in Overland Park
'64 E OTS

 

Goodmorning Bob. Just got message, but I was at crown center for the show on Saturday, pretty sure I saw your 64 there in the concourse section as usual. Still a beautiful car.
in regard to the ameter, I got mine working. , I located a diagram (from the alternator supplier). Of course they didnt say it would work,, but that the diagram is a generic for this unit. It required me to take the lead from the new alternator straight to the ammeter, bypassing the factory solenoid. Then a jumper from the ameter to the ignition switch, allowing power from the switch to read the drain on the battery. So now it reads correct, charging when it revs up, discharge when it doesn't. I also thought of the voltmeter route, and a friend had one out of a triumph I believe, but all smiths gauges nearly the same. It will def read voltage, not charge or discharge, like original. If u decide not to change the original, as far as the amp draw, the gauge would peg at 30 amps. New equipment charges 45 for me, but thats only if it needs it, which the old e system doesn't. Even the wiring indicates that, since none of the wires are of a heavy enough gage to do so. Bottom line is mine now works correct. I read other similar links to this, some had indicated their gauge read too high, but they put in a shunt across the ameter to bypass heavier draw. Mine didn't need it. Fortunately the factory terminals actually provided a double connection for the jumper. If u decide to keep original, let me know if u need the diagram, or more information.

 

Appreciate your getting back to me. Very helpful information. Sorry I didn't meet up with you at show as I would love to compare notes. Yes, if you could email me a diagram or some detail photos I'd appreciate it.


Mine is set up with lead from alternator going straight to the neg terminal on battery as per WOSP Performance (manufacturer). Are you saying to additionally run a wire from this lead to the ammeter?


Have to admit I'm somewhat electrically challenged even though I install and service high end welding equipment. Would love to have you, at your convenience, stop by and lead me through the modifications you did to get your ammeter to work. Happy to pay you for your time. Garage is air conditioned. Oh....and I have a fairly high end race simulator with LeMans Jags on it so you're welcome to come play.

Bob Gilmore 913-908-8929
jagnutz@swbell.net