| [GMCnet] Excessive voltage at 1500 rpm [message #347538] |
Mon, 09 September 2019 07:39  |
Jeff Von Haden
Messages: 3
Registered: June 2019
Karma:
|
Junior Member |
|
|
Thanks for all the advice on solving my issue with excessive voltage...
Backstory... replaced regulator and still had 16-16.5 volts when over 1500rpm. Alternator tested fine at auto parts store.
I then took the ideas sent and explored.
- Cleaned and tightened the connectors on the alternator, including the voltage sensor wire. No difference.- Disassembled and cleaned the connections at the battery switches, starter solenoid, battery isolator. No difference.- Disconnected the aux battery from the battery isolator. Seemed to solve the problem... I reattached the aux battery to isolator and excessive voltage came back. Disconnected and excessive voltage went away. At that moment I'm thinking the isolator or something in the house wiring is my issue.
With the house battery disconnected from the battery isolator I took it on a test drive at dusk. Was working fine until I turned on the headlights. With the lights on, at 1500 rpm the voltage would pulse from 14 to 16+. At 2000 rpm alternator light was on and if I remember correctly my meter was reading 18 volts (higher than the 16 volts I had seen with house battery attached). When I turned off the lights the voltage went back down to 14, even at 2500 rpm.
I'm not sure what an isolator will, or should do, when you only have the starter battery attached...
I used my meter to test the battery isolator diodes and if I tested correctly, there is no flow in either direction. Is that a possible failure mode?
So my inclination is to replace the isolator and see what happens, but was hoping for your thoughts before I became a parts changer...
And if you think replacing the isolator will help, what are your thoughts on going to a solid state isolator rather than the standard diode isolator?
Thanks for any advice you can give,
Jeff Von Haden76 Palm Beach
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
