sirfinn
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Engine Performance Problem with Main electrical switched to "On", runs better "Off"
Hello,
Working on a new to me 81' M35A2. In fact, just drove it home this weekend after putting a new T-case in it and brake bleeding, windshield, and fluid changes.
The previous owner complained that the engine power was very poor with the electric switch on, when it is shut off, it runs much better but will only rev to about 2k up or down hill(maybe the lack of in-tank fuel pump(off) or dirty filters), the it acts like it is limited on fuel. Everything runs fine at idle, and the charging system gage is in the green.
After disconnecting the power to the fuel pump and it had trouble starting, plugged it back in and started right up. During the drive home, running the headlamps and drawing down the battery, the belt was slipping when the power switch was turned on after running for an hour. It did not slip at the begining of the journey. The in-tank fuel pump whines when the switch is turned on "on", the batteries are setup negative to ground, it has the stock style 60Amp alternator, but it seems like the alternator is acting like a driveline retarder... maybe.
If it were a generator, my guess would be, it had reversed polarity. Is it possible the alternator was connected wrong and is acting like a reversed polarity or the regulator is wired up backwards?
According to the diagrams, it appears to be wired to the truck harness correctly. Is it possible the alternator field is backwards. Any thoughts on how to verify this or rule it out?
It could be a fuel pump, but it does not seem likely since it helps with starting.![Confused :???: :???:](https://www.steelsoldiers.com/images/smilies/icon_confused.gif)
The plan of attack is to solve the electrical issue first, then fuel filters and tune-up next. I will dig-in with a volt-ohm meter and isolate the alternator next. This is a very strange problem.
Thanks for any ideas!
-Sirfinn
Hello,
Working on a new to me 81' M35A2. In fact, just drove it home this weekend after putting a new T-case in it and brake bleeding, windshield, and fluid changes.
![Driver :driver: :driver:](https://www.steelsoldiers.com/images/smilies/driver.gif)
After disconnecting the power to the fuel pump and it had trouble starting, plugged it back in and started right up. During the drive home, running the headlamps and drawing down the battery, the belt was slipping when the power switch was turned on after running for an hour. It did not slip at the begining of the journey. The in-tank fuel pump whines when the switch is turned on "on", the batteries are setup negative to ground, it has the stock style 60Amp alternator, but it seems like the alternator is acting like a driveline retarder... maybe.
If it were a generator, my guess would be, it had reversed polarity. Is it possible the alternator was connected wrong and is acting like a reversed polarity or the regulator is wired up backwards?
According to the diagrams, it appears to be wired to the truck harness correctly. Is it possible the alternator field is backwards. Any thoughts on how to verify this or rule it out?
It could be a fuel pump, but it does not seem likely since it helps with starting.
![Confused :???: :???:](https://www.steelsoldiers.com/images/smilies/icon_confused.gif)
The plan of attack is to solve the electrical issue first, then fuel filters and tune-up next. I will dig-in with a volt-ohm meter and isolate the alternator next. This is a very strange problem.
Thanks for any ideas!
-Sirfinn