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ktom300
12-19-2008, 11:44 AM
I have a 24V FFR lightweight and when I first got it I could get 28V at the batteries during operation so I assumed it was working.
A few hundred miles later I can not get the 28V anymore and my batteries go down after a few days of short trips and repeated starting.
The system is all shielded with a ~24 pin connector/harness. What pins do you test at for output right at the alternator?
Also, does anyone repair these things? They appear to be difficult to find and a bit pricey.

Thanks,

Tom
Jeff Aronson
12-19-2008, 01:22 PM
Since I don't work physically at Rovers North, I can't say whether they have the 24v alternators - it's certainly worth a phone call.

As for testing, you could make it easier by going to a NAPA-Carquest and picking up a digital multimeter. They can read voltages at the battery, and then again at the cable end [let's you know if there's a poor connection at the terminal]. With the car running, test the alternator output. On a 12 v system, the battery should be between 12-12.5 v at rest, and then 14 when started. If there's no change, then I'd know the alternator wasn't charging the system.

Just in case this is easy, remove the battery cables and clean the terminals and the inside of the battery connectors. Then remove each pin and wire connector one by one at the back of the alternator and clean those terminals. I've been fooled before by corroded terminals at each location.

Jeff
leafsprung
12-19-2008, 01:34 PM
On a 12 v system, the battery should be between 12-12.5 v at rest

that would be less than 100% charge. 12.6 or 7 would be 100% and on a gel cell sealed type more like 12.9 as high as 13.4 (I just checked a redtop optima for giggles in the shop and it was 12.85 and Ive used it for testing parts so its not 100%.
ktom300
12-19-2008, 05:10 PM
I have a fluke test meter and I used to get 28V at the batteries. Now I don't.
I'm all for testing at the alternator but it's a huge shielded connector with ~24 pins. I think the outputs are the two large pins but I can't be sure.
Does anyone know for sure?