In need of some alternator advice
07-20-2017, 10:21 PM
#41
Just a FYI/ Food for thought since this may be a heat related item, and a rock that we may have not turned over yet.
If you get your hands on a 30 amp load meter, then may want to check out the radiator fan . GM really did not design the radiator fans be driving hard all the time, and the motor bearings in them love to start to wear out quickly when they are over drive for too many hours.
So the quick test here is to jump the leads from the PWM, cycle the radiator fan at 100% and take the amperage reading, and it should be drawing just under 25 amps full blast. Next, with the motor unplugged, or with no power to the fan motor, spin it by hand to make sure it free wheeling with no binding.
So what happens as the bearings in the motor start to wear out, it causes the fan motor to pull more amp that it should, and this could be the power draw over just a bad connection in one of the charging wires when the heat is blistering.
Granted pulling the radiator fan, and then pulling apart to change the bearings is not for the meek, it is tangible never the less. The bearings only run about $7 for both ends, over hundreds for a new fan instead.
Short version,
Back Case cover is retained on via the V bent tabs, so pressing them in will allow the back of the case to be removed. From here, lathe comes in handy to chuck up on the armature rod just past the back bearing , allowing you to spin off the front hub from the shaft, and now you can remove the armature from the motor housing.
At this point, both bearings are replaced on the armature shaft , the motor put back in order in the reverse order, and then case tabs Re'V'd to secure the back plate on again.
To add while we are on the subject of the radiator, now would be a good time to not only check for something blocking it, but doing a powder wash of radiator behind the A/C heat exchange as well.
Hence bag or something else caught in front of the heat exchange is going to cause the fan to run at max, as well as debris in-between the front of the radiator and back of the A/C heat exchanger.
To wash between the two, you can loosen the heat exchanger without disconnecting the A/C Freon lines to slightly pull the exchange forward away from the front of the radiator, and this gives you plenty of room to get in there with a garden hose and nozzle to clean both coil units out.
If you get your hands on a 30 amp load meter, then may want to check out the radiator fan . GM really did not design the radiator fans be driving hard all the time, and the motor bearings in them love to start to wear out quickly when they are over drive for too many hours.
So the quick test here is to jump the leads from the PWM, cycle the radiator fan at 100% and take the amperage reading, and it should be drawing just under 25 amps full blast. Next, with the motor unplugged, or with no power to the fan motor, spin it by hand to make sure it free wheeling with no binding.
So what happens as the bearings in the motor start to wear out, it causes the fan motor to pull more amp that it should, and this could be the power draw over just a bad connection in one of the charging wires when the heat is blistering.
Granted pulling the radiator fan, and then pulling apart to change the bearings is not for the meek, it is tangible never the less. The bearings only run about $7 for both ends, over hundreds for a new fan instead.
Short version,
Back Case cover is retained on via the V bent tabs, so pressing them in will allow the back of the case to be removed. From here, lathe comes in handy to chuck up on the armature rod just past the back bearing , allowing you to spin off the front hub from the shaft, and now you can remove the armature from the motor housing.
At this point, both bearings are replaced on the armature shaft , the motor put back in order in the reverse order, and then case tabs Re'V'd to secure the back plate on again.
To add while we are on the subject of the radiator, now would be a good time to not only check for something blocking it, but doing a powder wash of radiator behind the A/C heat exchange as well.
Hence bag or something else caught in front of the heat exchange is going to cause the fan to run at max, as well as debris in-between the front of the radiator and back of the A/C heat exchanger.
To wash between the two, you can loosen the heat exchanger without disconnecting the A/C Freon lines to slightly pull the exchange forward away from the front of the radiator, and this gives you plenty of room to get in there with a garden hose and nozzle to clean both coil units out.
Last edited by Dano523; 07-20-2017 at 10:25 PM.
