? re 6-71 12V generator? Is this one a split field gen?

[zubzub]

Finally got around to working on my charging system.  Tried all the manual stuff to get charge but as the gen on my engine is not the one in the book it's complicated.  This is what it looks like.

Top red wire is marked "F"
Side cloth covered wire is marked "2"
Big fatty is obviously armature and not seen,  15 deg or so behind the "F" is the "G" spot.
Casing has "D18" stamped into it, i.d. tag is too worn to read other than Delco Remy and 12V
The manual mentions split field generators and I think this is one as it has an extra connection marked "2".  
I tried connecting the armature to the field with the engine running (as per the Manual) but all I managed was a reverse current situation (battery V went down)
So I pulled the gen (PITA as you need to pull the comp to get at one of the gen bolts)
Bench tested it.  I started with an old way I have...current to (+)armature and ground and it's a fine little motor.
Next I tried the same field test but this time using a drill to drive the gen (aprox 500 rpm)
tried various combinations finally found that by connecting armature to "F" position and bridging "2" to "G" with "G" of course already grounded I was making power...not tons but my drill was getting bogged down (HD  mixing drill so some charging was trying to happen).
Looking for input here
 I'm guessing the PO just bought something that would fit on the engine but not the right V reg as the one that came with it matches neither the book not has an extra field connection point.  As you can see this is an older drive system
Generator is about 19" long with drive attached.  
I had hoped to get something of a transit to drop in but the transits in the yard  have an offset drive with a different circumference in the 5  hole pattern.
I kind of hate gens and was hoping to install an alt, but with this drive issue I am reluctantly considering working this thing out.
 Any kind words appreciated.  Patrick.

[Just Dallas]

Removed

[gus]

Pat,

My best suggestion is to use the electrical diagrams in the back of the book, they are pretty good for old stuff.

You didn't mention flashing the field. Old generators must be flashed and not doing that can cause reverse voltage output.

I think the manual will tell you how to flash it. If not you can probably go online and find out how to do it.

I've done many of them but each seems to take a different method and I don't want to give you the wrong info.

[zubzub]

Thanks Dallas and Gus, I flashed the field but really this gen has never worked on the bus.  Like I said I can get it to work but baring tons of info re bench testing this model and acccess to a v reg that works with it and the bus I will have to look elsewhere especially after  i looked up split field gens online.....now I really want an alternator! This bus has never charged, I don't have the proper V reg for it or even a manual for the gen  If anyone wants a nice recently rebuilt (from what I can tell) split field generator, there may be one in your future.  I would like to know where/what  to search for re: either a belt drive that I can bolt to the engine...or alt Names and #s that can be bolted to my engine (left turning 6-71 with centered drive output, 5 bolts aprox 8.5" across). As well as what vehicles may have the required bits on them.

[gus]

I can send you a photo of  my 4104 alt setup if you like.

It is pretty simple, has a plate with gear on engine side and pulley on outside. The alt is offset toward bus front with homemade brackets and very short double belts.

The alt is a common Leece-Nevill truck alt. The original was a 150a 3-wire but I replaced it with a 105a 2-wire which requires no exciter hookup.

[zubzub]

That would be great Gus especially where how the brackets are attached to the engine and a peek at the plate that covers the gear.  I may have to start a new thread looking for a source for the gear to belt converter unless someone chimes in with a source.

[gus]

Zub,

I sent the pics, did you get them?

[zubzub]

Yes and thank-you they were clear enough for me to know what the next step is.  Patrick.

[Len Silva]

You can get the Coach Info procedure guide here:  http://coachinfo.com/Manuals/Coach/GMC/4104.html for $20.00.  Sorry to say, I gave mine away when I sold the bus.  The important stuff is the DD parts to add a camshaft pulley.  I'm sure many folks hear can help with that.

[dp4104]

Jub,
I have a copy of the procedure, a fax number could save you $20 bucks and some time, it does have a parts list with part numbers!I haven't done this yet, but the procedure looks pretty simple.
I asked for the pictures too.
Thanks
Dave H
hancockdaveh@aol.com

[gus]

Dave,

Pics on the way.