Generator shaft repair
 

I run a late model generator with the fan attached on my '34 pickup. it has a 1953-54 flat 8BA. The generator armature shaft is worn where it fits to the front bearing. Is there a repair for this area of the shaft? I had thought of building up the shaft and then machine it down. However I was warned about heat so close to the windings. Is there a source of new armatures? Thanks in advance, Byron.

Re: Generator shaft repair
 

Build it up with j b weld then machine it. Gary

Re: Generator shaft repair
 

If the steel shaft has worn, why won't the JB wear even sooner? Byron.

Re: Generator shaft repair
 

The jb weld is to center the shaft in the bearing, you will neen a new bearing most likely, then when you assemble the gen pulley tight thats is the reason for the wear! the fit to shaft is easy hand fit not tight. ernie n tx

Re: Generator shaft repair
 

need, the bearing has been spinning on the shaft, tight fit pulley to bearing to sholder on shaft is key . e

Re: Generator shaft repair
 

There is a product for fixing shafts that are worn under a seal so they leak. It is a thin sleeve of stainless steel that is used to repair the shafts, you may be able to find it in McMaster Carr, or the other thought is to take it to a machine shop and have them sleeve it.

Re: Generator shaft repair
 

Byron-

Armatures, especially 8BA are a common occurrence on epay. However, if you still can't come up with one you might want to give some serious consideration for a Redi-Sleeve. These things come in a multitude of sizes and can be slid on the shaft using a common 100 watt light bulb for heating. Most auto parts store such as NAPA or Carquest can get them.

Tom

Re: Generator shaft repair
 

Byron,
Perhaps JB weld will work....I hope so.
Redi Sleeves have about a .005 wall and are fine for running a
seal on because the seal has lots of give to it. A bearing doesn't give at
all so tread lightly.
If however you post a photo of your armature I'm sure many
of us horders will have a replacement. If you choose to post a photo lay
a 12" ruler along side the armature so we get the right one.
OMO,
Charlie ny

Re: Generator shaft repair
 

I like Charlie NY's idea... I will further that, with another armature, you won't be thinking about pushing the car when far from home...
Karl

Re: Generator shaft repair
 

Byron-

I have been re-thinking my previous answer and I think the solution to your quandary may be easy. I have taken apart a lot of generators over the years and have found many that have difficult to take off front plates. When I eventually get the plate off I have seen the shaft portion of the armature where the bearing sits has been "staked" with a center punch. This raises the armature shaft surface. As a result, the lower shell of the ball bearing cannot rotate on the shaft. When this is done all the rotational motion is being done by the bearings (as it should be). If you are experiencing wear on the shaft it probably indicates a bearing problem that forced the armature shaft to act as the main bearing surface, which it was not intended to do.

After "staking" the armature shaft, slide the (new) bearing on the shaft (now assembled on the the front plate). If every thing is as it should be the bearing will need to be nudged into place with a socket and a few light taps with your favorite hammer.

I have seen enough of this "staking" that I have often wondered if it may have been part of a factory manufacturing process or at least a common repair in the past. At any rate. give it a try. If it doesn't work just file down the "staking" and go to your plan "B."

Hope this helps.

Tom

Re: Generator shaft repair
 

Tom and other Barners: Thanks for your replies.I was prepared to use the JB weld on the shaft and hope it would get a good grip using the scarring on the worn shafts for extra grip. However "flatheadfans" idea is also appealing. Tom, would you use several peens of the centre punch to raise up the shaft? I noted that the bearing slides into the end plate before it then slides onto the shaft. But that is no problem. Byron.

Re: Generator shaft repair
 

If you use FHF's idea which sounds pracatical to make up .005 or so be sure
to use locktite to help 'steady things'.
Charlie ny

Re: Generator shaft repair
 

I have a never used remanufactured armature for a 36 genny & it has been staked where the bearing sits , I was quite supprised to see this when I opened up its box . I would also do a Charlie NY suggests & loc-tite it.
Cheers
Tony

Re: Generator shaft repair
 

Bryron-

If I was in your situation, dealing with a worn armature shaft, I would center punch about 7-10 dimples in the bearing seat on the armature shaft and then attempt to slide the bearing on the shaft. It should slide on with some effort but not enough effort that the bearing would be damaged from being forced on. If needed put some more dimples in the shaft or file down some of the dimples that you originally put in whatever it takes to get the tight fit you need. Once you are satisfied with the fit place the bearing with the baffle plates and two felt washers into the end plate. As you probably know, everything is held into the end plate with a snap ring. Once this is done slip the entire plate on to the armature shaft and use a socket and hammer to complete the job. That should do it!

Hope this helps.

Tom

Re: Generator shaft repair
 

Checkout your local electrical too/motor repair shops or machine shop to find one that can KNURL the shaft better than peening/staking used this all the time when running a electric motor repair shop. The armature or shaft is centered in a lathe & this tool will make hatch crossmarks to hold the bearing.
To find out more on KNURLING try GOOGLE

Re: Generator shaft repair
 

There is one listed on e-pay for 25.00 N.O.S, I p.m. the info. to you on on a couple I had on watch.
Good luck,
fordestes

Re: Generator shaft repair
 

https://jdparts.deere.com/partsmkt/d..._Compounds.htm

R

Re: Generator shaft repair
 

I like bobs idea ,another opshion is to make up a shim using somthing like a tin can .fold up the ends with little cuts in it all round ,Or weld the shaft t using running water & hose to cool the amiture .

Re: Generator shaft repair
 

Thanks for all your help, Byron.

Re: Generator shaft repair
 

In response to JONC, The sleeves JONC mentions are called "Red-i sleeves" from Federal Mogul National seals or "Speedi- sleeves" from Chicago Rawhide Seals. Most any Automotive or truck parts distributor should have them available. Not sure about how small they make them though.

Rich O.