Play in generator shaft

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71whitewesty
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Play in generator shaft

Post by 71whitewesty » Mon Jul 06, 2020 11:17 am

Hello folks, anyone here ever experience play in their generator shaft?
Have a fairly new rebuilt generator with about 7k miles on it. I've always noticed sort of a hummm from this generator but otherwise it's working just fine. But I have some play in the shaft it seems. Maybe a 1/16th inch when pushing it back and forth like checking the end play. It has a slight turbo sound to it now when I rev the engine. I have not looked into it much, have not pulled off the belt even. Pretty sure it's not a loose fan or generator strap of pulley. Seems to be just in the shaft.
I may just try to get another generator but wanted to ask some experts first to see if anyone has experienced it and what they did to fix it. Thanks for any help or suggestions.

kreemoweet
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Re: Play in generator shaft

Post by kreemoweet » Tue Jul 07, 2020 9:05 pm

1/16 inch is huge. I hate to think what kind of carnage that's causing at the brushes/commutator. I've never been able to "feel" any axial play in any VW generator or alternator, although there
surely has to be a little bit. Likely the rebuilders left out a shim, or used a wrong or grossly worn part, and clearly
left out an important step in the Quality Assurance check. I'd pull the thing apart and see what was needed to
save it. I assume this is a rebuilt stock 38A generator? Valuable!

71whitewesty
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Re: Play in generator shaft

Post by 71whitewesty » Wed Jul 08, 2020 9:57 am

Yes it was a stock rebuilt one. I forget off hand who did the rebuild but I know I paid dearly for it. I will take it apart and have a look but will order another one to stick in there in the meantime. It's just a matter of finding a good one.

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tommu
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Re: Play in generator shaft

Post by tommu » Mon Jul 13, 2020 3:11 pm

What are the new ones like? They're available from Cip1 and I've been considering picking up a spare.

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Amskeptic
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Re: Play in generator shaft

Post by Amskeptic » Tue Jul 14, 2020 3:43 pm

71whitewesty wrote:
Wed Jul 08, 2020 9:57 am
Yes it was a stock rebuilt one. I forget off hand who did the rebuild but I know I paid dearly for it. I will take it apart and have a look but will order another one to stick in there in the meantime. It's just a matter of finding a good one.

I bought a stock rebuilt 38a generator from Always Veedub in Portland for $138.00 that had a wallowed out end plate with a crinkly shim to sort of hold the chinese crap bearing in place inside the bore. Lasted maybe 40,000 miles. Miserable vibration and axial/radial play. These generators, hello! are geared up 1.6:1 on an engine that frequently sees 4,000 rpm! The generators are driving a big sheet metal fan, too! The bearings need to be top drawer and the endplay really should be close to zero. I scored an original German bearing that is running fine with another 60,000 + miles on it.

#6203. 17x40x12mm (ID/OD/width)
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 118,840 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 89,009 miles

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asiab3
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Re: Play in generator shaft

Post by asiab3 » Thu Jul 16, 2020 9:55 am

Turbo sound? Check the fan for a rag or other obstruction!

What is the thrust-governing surface surface? My Bentley is 1,200 miles away...

My 38-amp has five to ten thousandths of discernible end play, and the bus next to me has about a sixteenth of an inch...

BusDepot sells rebuilt 38-amp generators, but as all BusDepot/Cardone collaborations go, you won’t be able to install them without modification... Remove the M6 washers under the loooong flathead bolts, and the cast iron pulley should fit.

Good luck!
Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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Amskeptic
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Re: Play in generator shaft

Post by Amskeptic » Sun Jul 19, 2020 7:16 pm

asiab3 wrote:
Thu Jul 16, 2020 9:55 am
Remove the M6 washers under the loooong flathead bolts, and the cast iron pulley should fit.

Good luck!
Robbie
Thanks for the tip. Should I spring for a new generator for Chloe?
Colin
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 118,840 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 89,009 miles

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asiab3
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Re: Play in generator shaft

Post by asiab3 » Mon Jul 20, 2020 11:21 pm

I would get one just to have it. Unfortunately, they paint them black, so the bling factor is high/low depending on where you’re coming from...
Me? I’ve got six more in the stash, in various states of repair. I’ll hold off.
Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

71whitewesty
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Re: Play in generator shaft

Post by 71whitewesty » Wed Jul 22, 2020 9:49 am

Thanks guys. The turbo sound I think is the fan lightly rubbing on the shroud but it goes away or at least I can't hear it at speed. I bought a used generator off the samba and it looks good, cast iron pulley and all. I'm going to yank out the engine and replace it in the next day or two. That way I can get a good look at the shroud and really see what's going on. The one that's in there is still working and I'll take a look at repairing it if it's possible.
On another note, I visited Ken at the Busco the other day and picked up a new fan, some thermostat flaps for my spare engine and a sway bar for Bus 1 which has been broken for who knows how long. I finished installing the sway bar yesterday and it went pretty smoothly. A liberal amount of Kroil soaking over 4 or 5 days made all the difference.
I'm going to miss the Bus spa day this year, they can always use it.
We are shooting for a Moab type Bus trip this year mid Aug. So got to make sure things are solid as I plan to power drive the bus to maximize the time there.
Hope you all are doing well and staying healthy.

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