Have 85 F250 diesel, had not been in use for a couple of years. New batteries and started fairly easily. Overnight the batteries were dead, recharged and started fine. Found a voltage draw (with the key off) between + terminal and wire to the glow plug solenoid and starter relay. Removed from glow plug, still had voltage draw removed from start solenoid still draw. Thought might be bad altenator and replaced it and voltage regulator removed from start solenoid still draw. Home made remedy put a switch between + terminal and the wire to the solenoids, no voltage draw, but now the amp meter will peg at 70 amps when engine reved and the voltage goes to 20+ volts. At idle voltage is 14 volts and 15 amps. Burned out the headlights when engine reved up. Took new regulator back and got a replacement, still have highe voltage output and high amp output. Any suggestions

 

Take that switch out first, that sounds like it's messing with the regulator's ability to control the charging.

How are you checking for a drain? Just curious. You should next pull each fuse one at a time out of the fuse box till your drain goes away. But remember, you will always have some drain, that's why I asked how you are checking it.

 

Watching the amp meter, did remove all fuses one at a time did not have any effect on the amp meter, still showed discharge. As there are not electronics in this truck what would cause some drain? I will take the switch out of the circuit, and try again.
Thanks for the advise

Dave

 

What value is your ammeter showing? If you have a radio with a radio station memory, it will show some draw. But the draw is usually very low, less than .07 amps.

As far as finding the draw, this is how it goes; You have the alternator connected to the solenoid wiring like you stated. I would leave all the solenoid wiring connected, and disconnect the alternator wiring on back of the alternator. I know it's new, but let's just verify it again.

There is another wire hooked to the solenoid, that connects the keyswitch and the hot all the time part of the fuse box. So pulling the fuses and having the key off should have taken care of that part.

The only other thing you could have is stuff that is added to the battery by someone else. See if there is any added wiring that could be causing the draw.

 

All is happy now. Did as you instructed, removed the switch, replaced regulator, noticed mounting plate did not appear to be grounded, added separate to regulator mounting plate. charges at 13.8 volts, amps drop to < 5 after batteries are charged. Amp meter does not move now with the key off. Don't know for sure if it was the added ground, a defective regulator, the switch, or something else (loose/bad connection) which were corrected when I was chasing the wires.
Anyway thanks for the help.
Dave