MTFCA Forum

Number one is the less pressing problem, the car gets weak spark on magneto and backfires. I cleaned off the terminal but we were told when we bought the car it flat out didn’t work. What could be the cause of this? We have just ran the car on battery this entire time so it is more of just a wonder instead of a real problem but ideally I would like to fix it. Problem two, the ammeter suddenly stopped working when the car was fired up today, I hooked 2 different ammeters to the wires and neither registered any charge of discharge, what could be the cause of this, it is a newer ammeter from macs.

Year of car would help on the ammeter question. For the magneto function search on in car recharge. You magnets may be weak.

Don’t run the motor until you ground the generator, it my be to late though but id still ground it just in case by attaching a wire from the generator post to one of the screws holding the cutout on.

The car is a 21 T coupe if that effects anything

Which post on the generator are you speaking of

The terminal post that is coming out of the generator. Did you drive or run the T any distance/ length of time after you noticed the meter stopped working?

The car was running for about a minute before I noticed the ammeter wasn't on then shut off almost immediately.

You may have saved the generator but until you determine what the issue is you should ground the generator so it won’t burn out while the motor is running.
Several things to check that may be the issue.
Wires are connected & tight at the amp meter & switch
Wires at terminal block connected & tight
Wires to cutout on generator connected & tight
Small screw connecting wire on cutout toward the front is not touching the generator housing
Frayed wires anywhere
I assume based on you trying different meters with no charge or discharge that it’s not the meter but could be you can check for continuity

Others may have some better suggestions but that’s a start
Good luck John

Back firing would have me looking @ the switch internal connections. Does the switch feel tight @ both positions or loose? An analog voltmeter is needed to check the source output of both the magneto & generator before the ammeter.

For Instructions on in car magneto recharge put this link in your favorites.
https://www.mtfca.com/discus/messages/5 ... 28397.html