Charging woes

[Amskeptic]

Is there a way to test? And can the diodes be replaced?

I think you will be best served with a new/replacement alternator with warranty. That diode plate is a mean assembly with the additional stress of having to un-solder/solder with skill.
Colin

[appetite]

I was defeated today. I think I made things worse.

I tried the test dingo suggested. I got a reading of 25.5.

So I went back into the alternator to see if anything could be cleaned. Pulled the brush assembly. Did the eraser cleaning. I put it all back together.

Now I don't have any GEN light. Maybe I broke a connection. I opened it up multiple times to make sure the spade connectors were tight.

And obviously the alternator isn't charging at all now. Started it up, turned on the headlights and pulled the neg from the battery. Died instantly.

I'm stepping back to try to figure my next move. Anyone have a favorite vendor for a replacement alternator?

James

[kreemoweet]

. . . pulled the neg from the battery.

Perhaps you've overlooked the WARNING that appears in the VW service manuals (and many others, I'm sure):

"CAUTION: An alternator must never be run without a battery. Doing so will severely damage the alternator, the regulator, or both."

Genuine Bosch AL82's are still available:
https://www.amazon.com/Bosch-AL82N-New- ... dpSrc=srch

[appetite]

Well kreemoweet, it was the last thing I did, and I reckon the alternator's issues were already established.

Before I swap the alternator, I'm going to see if I've done something stupid to the brush assembly. Maybe there is a connection loose.

James

[appetite]

Knowledgeable forum,

I've been stripping away engine parts as per Colin's instructions to get the alternator out, but i am stuck on this step:

"Remove...both 10mm bolts from fan housing-to-upper tins, dog house tin, then doghouse outlet tin."

Forgive my ignorance, but after quite a bit of searching for images, i don't know where these bolts are located. Are they behind the fan shroud somewhere?

Also: is there supposed to be a dedicated ground wire on the alternator? There's a screw on the body of the unit....

Thanks for your help.

James

[asiab3]

See the hex bolt in the bottom right? Fasteners #1. See the hex in the top center? Fasteners #2!




The triangle tin comes off and the third fastener is uncovered.

Robbie

[kreemoweet]

If you please, sirs, leave us not forget fastener #4, the fan-shroud-to-Hoover-bit bolt, visible at the left side of photo above.

[appetite]

Oh fantastic. Thanks very much.

Back at it for me!

[Amskeptic]

If you please, sirs, leave us not forget fastener #4, the fan-shroud-to-Hoover-bit bolt, visible at the left side of photo above.

^ ^

[appetite]

Holy crap, that was a pain in the ass.

But it is out:

https://www.flickr.com/photos/23704155@ ... ed-public/

and

https://www.flickr.com/photos/23704155@ ... ed-public/

I brought the alternator to a local shop to get the big 36mm nut off. I don't know how I'm going to get all these parts back together, but it's a start.

Any tricks or warnings of things i should be aware of?

Thanks,

James

[appetite]

OK, so, shims...

Should I just use the same number of shims that were on the old alternator, regardless of recommendations otherwise?

To wit:

1. There were these two beefy shims between the wavy washer and the fan:

https://www.flickr.com/photos/23704155@ ... ed-public/

I have not seen these thick shims in any other description of the install.

2. And there were a handful of thin shims between the hub and the backing plate:

https://www.flickr.com/photos/23704155@ ... ed-public/

Again, most descriptions don't include these.

Any ideas?

[Amskeptic]

Holy crap, that was a pain in the ass.

Any tricks or warnings of things i should be aware of?

Thanks,
James

YES! I have WARNINGS GALORE.

a) this is rapidly spinning machinery, far more rapid than any of your other cars. Please make sure the fan runs true, is bolted up securely on clean flanges, clean shims, clean hub, and is correctly aligned front-to-back in relation to the crankshaft pulley.

b) the Bentley calls for a 2mm gap between the big black circle that bolts to the fan housing with those four 10mm bolts and the fan itself. Make it so by adding or subtracting shims between the hub and the fan. Make sure there is no rubbing at every step of re-assembly. Make sure that the big black circle plate is correctly oriented to the fan housing so the cooling duct faces down and is correctly oriented to the alternator so your electrical terminals are where they were.

c) if there is rubbing at start-up, loosen the hold down strap, the fan housing side bolts, then restart engine and gently push or pull to see which way erases the rubbing sound. Then, tighten down with a little "english" in the quiet direction.

d) disconnect the thermostat from the bracket and run the thermostat up and down after assembly is done to ensure that the rod hasn't jammed.

Other than that, have fun.
Colin

[kreemoweet]

The fan nut lock washer orientation is quite important:



Also, the backing plates used for the alternators on the upright engine should be the same ones used by the
type I 30A generators. The busses that had 38A generators used a different set of backing plates, and they should not
be used with an alternator. Doing so would likely result in misalignment between crank and alt pulleys.

[appetite]

Thanks all.

kreemoweet: I am using the same backing plates that were attached to the old alternator.

Colin: Just to clarify, should I use the same number of shims that were on the old alternator (the thick ones and the thin ones)? There's nothing different in the set-up; I am installing an identical alternator and using all of the old parts (fan, backing plates, etc.)

[appetite]

The thrill of victory! The agony of defeat...

Victory:

I can't believe it it, but I got everything reassembled. I reverse engineered everything I took apart, and it all went smoothly. I had to use those thick shims on the fan hub, because I think the hub is longer than others I've seen when searching around for examples. No rubbing when I had spun the fan, no rubbing when I spun it by hand in the fan shroud, and the alternator pulley lined up with the crankshaft pulley.

Defeat:

Of course the bus will not start. It tries to turn over, to no avail. I think fuel is getting to the carb (I can smell it). It cranks and cranks but never catches. So I don't know whether all of this this was for naught.

There was a mystery black wire that must of fell off of something as I was wrestling parts. I hooked up to the coil because it was long enough and angled in such a way that made me believe that's where it came off of. That might have been a mistake. On the first attempt to start-up, there was a noxious smell and that wire got hot to the touch. I removed it, and will need to trace it out of the firewall to see where it originates.

I'm going to step back and reassess. Could I have fried the coil? Would that even effect start-up?

If anyone has any ideas, let me know.