First post here. I've been reading for a while but there's always something new to learn. Thanks for the great resource and community. It's helped my father and I troubleshoot everything from a leaking fuel pump to glow plug controller issues to leaking rear main seal to heater core replacement, etc.... It seams just our luck that every common problem with these vehicles has effected ours and even so it comes with the ownership of a 25+ year old vehicle. I enjoy the hands on experience.
My father had recently started using the m1009 as his daily driver as it seemed we had all of the "kinks" worked out until this recent issue.
On a trip to work he discovered the #1 alternator was overcharging the #1 battery and overheating it. Stranded, he took it to a shop who charged him an arm and a leg to troubleshoot and replace the regulator in the #1 alternator (common issue on the m1009 as I have read here). He drove it home and the next day the voltmeter indicator in the dash raised to the white line separating the green from the red overcharging zone. He took it back to the shop that overcharged him in the first place and they replaced the regulator on the #1 alternator, again.
He called me up and I brought over a multimeter to check out what's going on. When you first start the vehicle the voltmeter indicator in the dash sets nicely in the middle of the green. Then when you give it a little gas the indicator jumps to the white line in between the green and red overcharge and remains there even when you let off of the gas. It's like a step function increase in voltage when you rev the motor. Here are the voltage readings:
Key in off position
Gen 1 = 13.25V
Gen 2 = 25.90V
Batt 1 = 13.24V
Batt 2 = 13.02V
Batt 1+2 = 26.0V
Blazer first started
Gen 1 = 14.65V
Gen 2 = 27.00V
Batt 1 = 14.64V
Batt 2 = 12.95V
Batt 1+2 = 27.4V
After reving the motor and letting off back to idle
Gen 1 = 14.68V
Gen 2 = 29.20V
Batt 1 = 14.65V
Batt 2 = 14.83V
Batt 1+2 = 29.30V
In addition, at idle the Gen 1 light comes on (dimmed about 50%). As you rev the motor it gradually dims even more until it is no longer lit. Then when you let off of the gas the light comes back on (dimmed to about 50%). The Gen 2 light has never worked since we bought the vehicle.
I checked the voltage going to the voltmeter in the dash after reving the motor (indicator on white line) and got 28.9V which wouldn't necessarily alarm me.
I've also read here that the Gen 1 light can be affected by the heater switch. We recently removed the blower motor to check its condition after it began to sound like there was something caught in the blower cage. Turns out the motor itself was just warn out and requires replacing (rotor has a bunch of play). We didn't have time to go get a new one so we put the old one back in place until we had a chance to replace it. I think it's highly unlikely that just unplugging the connection to the blower could have effected anything but I could be wrong.
I know the alternator issue has been beaten to death, but I haven't found the smoking gun for my situation. Does anyone have any incite into what's going on?
Thanks,
Jeff
My father had recently started using the m1009 as his daily driver as it seemed we had all of the "kinks" worked out until this recent issue.
On a trip to work he discovered the #1 alternator was overcharging the #1 battery and overheating it. Stranded, he took it to a shop who charged him an arm and a leg to troubleshoot and replace the regulator in the #1 alternator (common issue on the m1009 as I have read here). He drove it home and the next day the voltmeter indicator in the dash raised to the white line separating the green from the red overcharging zone. He took it back to the shop that overcharged him in the first place and they replaced the regulator on the #1 alternator, again.
He called me up and I brought over a multimeter to check out what's going on. When you first start the vehicle the voltmeter indicator in the dash sets nicely in the middle of the green. Then when you give it a little gas the indicator jumps to the white line in between the green and red overcharge and remains there even when you let off of the gas. It's like a step function increase in voltage when you rev the motor. Here are the voltage readings:
Key in off position
Gen 1 = 13.25V
Gen 2 = 25.90V
Batt 1 = 13.24V
Batt 2 = 13.02V
Batt 1+2 = 26.0V
Blazer first started
Gen 1 = 14.65V
Gen 2 = 27.00V
Batt 1 = 14.64V
Batt 2 = 12.95V
Batt 1+2 = 27.4V
After reving the motor and letting off back to idle
Gen 1 = 14.68V
Gen 2 = 29.20V
Batt 1 = 14.65V
Batt 2 = 14.83V
Batt 1+2 = 29.30V
In addition, at idle the Gen 1 light comes on (dimmed about 50%). As you rev the motor it gradually dims even more until it is no longer lit. Then when you let off of the gas the light comes back on (dimmed to about 50%). The Gen 2 light has never worked since we bought the vehicle.
I checked the voltage going to the voltmeter in the dash after reving the motor (indicator on white line) and got 28.9V which wouldn't necessarily alarm me.
I've also read here that the Gen 1 light can be affected by the heater switch. We recently removed the blower motor to check its condition after it began to sound like there was something caught in the blower cage. Turns out the motor itself was just warn out and requires replacing (rotor has a bunch of play). We didn't have time to go get a new one so we put the old one back in place until we had a chance to replace it. I think it's highly unlikely that just unplugging the connection to the blower could have effected anything but I could be wrong.
I know the alternator issue has been beaten to death, but I haven't found the smoking gun for my situation. Does anyone have any incite into what's going on?
Thanks,
Jeff
