Like others I have the BNR 85 amp alternator off eBay, recently I noticed my dash volt gauge showed that it would at times not charge, and I sensed a slight squeal at high rpms so I decided to tear into it (it's good to have the gauge as the idiot light did nothing to indicate any pending failure). I've had the alternator for about 5 years.
They used chinese bearings in it so I ordered up some Japanese Nachi bearings from a supplier on Amazon named VXB. They are:
6203-2NSE
6201-2NSE
I also got a Bosch voltage regulator off eBay:
30 062
I removed the regulator, pulley, fan, woodruff key and fan back piece then removed the 4 screws that hold the body together. I used a cheapo Harbor Freight bearing puller to pull the cover off the front of the armature. The composite red winding section needs to stay in the body. Once off then the armature will come out and rear bearing needs to be pulled, I used the same puller but had to grind the arms down to fit under the bearing. Once off I cleaned it all up and painted the pulley and fan, new bearings shown on left and the front bearing is housed behind the hexagonal plate with 2 screws:
I noticed one of the wires had loosened from its connection so I resoldered all 3 and you can see where the rear bearing/armature fits in the cavity:
With wet 2000 grit paper I cleaned up the shaft ends, the 2 copper cylinders where the regulator connects and any other electrical connections I could find.
I reinstalled the bearings, the order of assembly is rear bearing on armature, armature into the main housing (above pic) then front bearing into cover then cover onto front of armature. The front cover has to be oriented so the regulator opening is at the 8 o'clock position relative to the main bolt hole assembly (at 12 o'clock position) in order for it to clear the oil filter (AMHIK):
Then the 4 screws need to be tightened a little at a time so the cover goes on evenly, spin the armature as you tighten the screws, if it stops spinning then back the screw out until it turns again then move to the other screws. Get them all tight while still spinning the armature. Also one of the 4 screws is longer so I installed it at the 11 o'clock position (see above pic), it sticks out the back and this is where I attach ground wires from battery and block and is accessible after installed in the car.
I reinstalled the fan and pulley but it semed to wobble due to the fan base not being flat so I heated the fan to +- 450 degrees then installed and tightened it back up and it's now flush with no wobble. I also adjusted/bent some of the blades so they all are equidistant from the body. All together:
Now the crap chinese bearings are out and with a new regulator hopefully will last for a while. I've heard good and bad about these alternators so for about $45 and a some elbow grease it appears for now it's charging as it should with quality innards.
They used chinese bearings in it so I ordered up some Japanese Nachi bearings from a supplier on Amazon named VXB. They are:
6203-2NSE
6201-2NSE
I also got a Bosch voltage regulator off eBay:
30 062
I removed the regulator, pulley, fan, woodruff key and fan back piece then removed the 4 screws that hold the body together. I used a cheapo Harbor Freight bearing puller to pull the cover off the front of the armature. The composite red winding section needs to stay in the body. Once off then the armature will come out and rear bearing needs to be pulled, I used the same puller but had to grind the arms down to fit under the bearing. Once off I cleaned it all up and painted the pulley and fan, new bearings shown on left and the front bearing is housed behind the hexagonal plate with 2 screws:
I noticed one of the wires had loosened from its connection so I resoldered all 3 and you can see where the rear bearing/armature fits in the cavity:
With wet 2000 grit paper I cleaned up the shaft ends, the 2 copper cylinders where the regulator connects and any other electrical connections I could find.
I reinstalled the bearings, the order of assembly is rear bearing on armature, armature into the main housing (above pic) then front bearing into cover then cover onto front of armature. The front cover has to be oriented so the regulator opening is at the 8 o'clock position relative to the main bolt hole assembly (at 12 o'clock position) in order for it to clear the oil filter (AMHIK):
Then the 4 screws need to be tightened a little at a time so the cover goes on evenly, spin the armature as you tighten the screws, if it stops spinning then back the screw out until it turns again then move to the other screws. Get them all tight while still spinning the armature. Also one of the 4 screws is longer so I installed it at the 11 o'clock position (see above pic), it sticks out the back and this is where I attach ground wires from battery and block and is accessible after installed in the car.
I reinstalled the fan and pulley but it semed to wobble due to the fan base not being flat so I heated the fan to +- 450 degrees then installed and tightened it back up and it's now flush with no wobble. I also adjusted/bent some of the blades so they all are equidistant from the body. All together:
Now the crap chinese bearings are out and with a new regulator hopefully will last for a while. I've heard good and bad about these alternators so for about $45 and a some elbow grease it appears for now it's charging as it should with quality innards.
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