15A
World's Oldest Brewery
- Joined
- May 7, 2004
- Location
- OH-MI....just like it sounds
I asked about how to service regulators or brushes awhile ago and got no response, so went digging myself. Found these are some of the easiest to rebuild out there.
A long time alt rebuilder on another site posted his tests as to the most efficient alternators out there. Densos were one of the highest, and Bosch one of the worst. A 100A Bosch at idle will put out about 45-55A. A 100A Denso will put out about 65-70A. On our 945T, when the electric fan kicks on when sitting in traffic its like a gut punch to the car. If it cycles at the same moment the AC compressor does also, I have moments of the dummy lights flickering. The 400w stereo and headlamps dont help either.
I recently had 2 Denso's in 2 different cars have the battery lamp illuminate with the key off or out.....which is indicative of a bad diode. Changing out the rectifier bridge, regulator and brushes - with new OE Denso parts, cost about $75 and took less than 15 minutes. You need a phillips screw driver, 8mm socket and 12mm socket (nut on the positive cable is an 8mm and can be a 13 if someone has replaced it).
Here is the patient.
Cover removed - if you only need to replace the brushes or regulator, this is as far as you'll need to go.
5 phillips screws to remove the brushes and regulator. Only 1 and 2 hold the brushes - all 5 hold the regulator. Make sure your new brushes come with the plastic guard and transfer it if not. Most do - some dont.
Next up - removing the rectifier bridge (diodes).
4 phillips screws is all that holds it in.
This particular one had 1 bad diode. I've had them that as many as 3-4 were blown. They're not hard to find.
Installation is the reverse....takes about 15min tops.
I have been buying the brush-regulator set on feebay HERE Less than $35 shipped. Great quality too.
The rectifier bridge / diodes can be bought from Maniac Electric Motors. What you need is PN 77904018 $37 shipped. Great quality.
The last one I had go bad wasn't charging the battery - putting out 12.4V at the posts. It had 3 bad diodes. Most of the other 5 didn't look too good either.
After changing everything out, it now puts out 13.8 - 14.2V.
Anyways.....hope this is clear as mud and helps some.
ONE OTHER THING TO NOTE......
The regulator I linked to is an IN442. There are also some for these labeled as an IN443. Both PNs and styles Denso lists for a 14V/100A Volvo alt. Only difference between them is the IN443 has Load Response Control (LRC) - from what I have heard, its helpful when you have something like a high load stereo system - but you can look it up to see if you want/need that or not. I have opened up about 10-12 of these and the last one was the first one I found that had it - here is the difference:
A long time alt rebuilder on another site posted his tests as to the most efficient alternators out there. Densos were one of the highest, and Bosch one of the worst. A 100A Bosch at idle will put out about 45-55A. A 100A Denso will put out about 65-70A. On our 945T, when the electric fan kicks on when sitting in traffic its like a gut punch to the car. If it cycles at the same moment the AC compressor does also, I have moments of the dummy lights flickering. The 400w stereo and headlamps dont help either.
I recently had 2 Denso's in 2 different cars have the battery lamp illuminate with the key off or out.....which is indicative of a bad diode. Changing out the rectifier bridge, regulator and brushes - with new OE Denso parts, cost about $75 and took less than 15 minutes. You need a phillips screw driver, 8mm socket and 12mm socket (nut on the positive cable is an 8mm and can be a 13 if someone has replaced it).
Here is the patient.
Cover removed - if you only need to replace the brushes or regulator, this is as far as you'll need to go.
5 phillips screws to remove the brushes and regulator. Only 1 and 2 hold the brushes - all 5 hold the regulator. Make sure your new brushes come with the plastic guard and transfer it if not. Most do - some dont.
Next up - removing the rectifier bridge (diodes).
4 phillips screws is all that holds it in.
This particular one had 1 bad diode. I've had them that as many as 3-4 were blown. They're not hard to find.
Installation is the reverse....takes about 15min tops.
I have been buying the brush-regulator set on feebay HERE Less than $35 shipped. Great quality too.
The rectifier bridge / diodes can be bought from Maniac Electric Motors. What you need is PN 77904018 $37 shipped. Great quality.
The last one I had go bad wasn't charging the battery - putting out 12.4V at the posts. It had 3 bad diodes. Most of the other 5 didn't look too good either.
After changing everything out, it now puts out 13.8 - 14.2V.
Anyways.....hope this is clear as mud and helps some.
ONE OTHER THING TO NOTE......
The regulator I linked to is an IN442. There are also some for these labeled as an IN443. Both PNs and styles Denso lists for a 14V/100A Volvo alt. Only difference between them is the IN443 has Load Response Control (LRC) - from what I have heard, its helpful when you have something like a high load stereo system - but you can look it up to see if you want/need that or not. I have opened up about 10-12 of these and the last one was the first one I found that had it - here is the difference:
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