Generator Noise

SoCalCoupe

SoCalCoupe

Well-known member
About a year ago I replaced some parts in my original 6V generator including brushes, springs, front bearing and rear bushing. Everything's fine electrically but over the past year it's gotten noisier and noisier. I know about lubricating the rear bushing and have done so. I have above average mechanical ability (my ancestors are from Lake Wobegon, Minnesota) and I installed the parts carefully myself.



Now, at idle, it sounds like I've got a cement mixer going under the hood. PROBABLY the bearing but won't swear to it. MIGHT be a water pump, but I doubt it. Really sounds like it's coming from the generator. Could even be internal engine noise but I really doubt it, seems external.


Would love to have some advice about isolating the noise. Also, if it's the front bearing as I suspect, what should I buy? C&G Ford Parts, where I bought the first one has one for $5.95. NAPA has one for $29.99. If only it were true that you get what you pay for, I'd gladly spend $29.99, but I suspect that's not the case. Perhaps there's some trick to aligning it correctly that I missed. Seemed like I had it square and fully seated.


HELP.
 
SoCal, your cement mixer description does sound like it must be a bearing, I'd be hard pressed to find a better word description, but I'll try: If it is from your pumps, it would have a muffled grumbling growl, if from your generator, a sharp crashing of ten pins at a bowling alley, the louder of the two.

What is bewildering, is your claim of mechanical ability emanating from the supposed location of a long running radio show that was so utterly stupid you had to listen every week. How does that match up with mechanical wizardry?
 
What happens when you squirt some WD-40 on the front and rear plates where the bearings are located.? Does the noise go away or lessen?


Also, when you remove the generator and take it apart and check the tightness of the fit of the armature in the bearing and also the tightness of the bearing in the front and rear end plates. Also check the armature shaft to make sure it's not rubbing against the field windings. Does oiling the rear bearing help?
 
HF sells a really nice stethoscope for a few bucks that has a long rod on it. Works much better than a long screwdriver and makes isolating weird noises a breeze!
 
ford38v8 said:
What is bewildering, is your claim of mechanical ability emanating from the supposed location of a long running radio show that was so utterly stupid you had to listen every week. How does that match up with mechanical wizardry?
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All of the children in Lake Wobegon are above average.


Took the belt off. It's the generator and not the water pumps or the engine.
Couldn't replicate the noise by hand spinning it. Some fore and aft play but didn't see any side-to-side play. Took the cover off and put it back on. Not the bearing or the bushing. MIGHT be the armature intermittently rubbing against the windings. Maybe the downward pressure of the belt is just enough to push it sideways.
 
SoCalCoupe said:
All of the children in Lake Wobegon are above average.


Took the belt off. It's the generator and not the water pumps or the engine.
Couldn't replicate the noise by hand spinning it. Some fore and aft play but didn't see any side-to-side play. Took the cover off and put it back on. Not the bearing or the bushing. MIGHT be the armature intermittently rubbing against the windings. Maybe the downward pressure of the belt is just enough to push it sideways.
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That wide belt doesn’t need a lot of tension so don’t over tighten it. I’d pull the generator apart and check if the armature is rubbing the pole shoes.
 
SoCal - there is an excellent shop in Fullerton, up the 5 from your location:
Fullerton Diesel Electric
1889 W. Commonwealth Unit P
Fullerton, 92833
714-870-4702 Doug Kemmling

He rebuilt my 49 starter, what a huge improvement, and the price was reasonable
and excellent quality and lead time.

For what its worth, he does all of Jay Leno's generator and starters.
 
The generator pulley should not move in/out at all, appears there are problems with the front bearing or its mounting. If you use a replacement bearing get one that is sealed with double rubber seals and use the original metal cups that are on both sides of the original bearing. You don't need the felt washers and you don't have to lube the bearing.
 
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Terry said:
The generator pulley should not move in/out at all, appears there are problems with the front bearing or its mounting. If you use a replacement bearing get one that is sealed with double rubber seals and use the original metal cups that are on both sides of the original bearing. You don't need the felt washers and you don't have to lube the bearing.
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That brings up a good point to remember about pumps: You come out one day and discover a small coolant leak at a pump’s pulley shaft, and you panic, replacing that pump without delay. NOT always the best practice. Better to check the belt tension, and give a little tap-tap to the end of the pulley shaft. These cooling systems have a lot of debris flowing through them, which can sometimes build up behind a pump bearing seal to cause a small leak. It doesn’t take much, and likewise doesn’t take much to clear and make a good seal again. Save yourself some grief and expense, keep an eye on it, and if it does it again soon, then you’ll know you can do a temporary fix and schedule a replacement at a more convenient time.
 
Terry said:
The generator pulley should not move in/out at all, appears there are problems with the front bearing or its mounting. If you use a replacement bearing get one that is sealed with double rubber seals and use the original metal cups that are on both sides of the original bearing. You don't need the felt washers and you don't have to lube the bearing.
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Betting a dollar that the in and out motion of the shaft is the causing the armature to intermittently rub against the field coils and making the noise. The shaft moves in and out with the generator belted up, maybe 1/8" or so. Looking at an exploded view of the generator, I see 10121 and 10122 washers between the front end and the bearing that will get bearing snugged up against the shoulder on the shaft. When I replaced the bearing last year I don't remember whether or not they were there but I didn't have any parts left over. Even if the felt isn't strictly necessary, maybe it helps set up the correct spacing too?


Can't tell about spacers/washers in the rear end plate, the diagram I have is for a newer generator that has a rear bearing rather than a rear bushing.
 
Took apart the generator again. The 10121 washer is missing. 1-1/16" ID, 1-3/8" OD, 3/32" thick. The thickness is exactly the amount of fore/aft play.


Anyone know where I could source one of these? Already looked at all of the Early Ford V8 suppliers I can think of. I'll try Home Depot but am not real hopeful.
 
That washer has a large ID for the pulley to pass through plus it is not flat, the steel material is about 0.023" thick The two washers on the rear of the bearing 10214 & 10098 have smaller ID and neither of them are flat. Having a stepped face helps to keep the felt seals away from the original open face bearing and hold the felt in place. With a sealed bearing there is no need for the felt seals and you can use flat washers of the proper thickness and OD with the ID big enough to clear the pulley.
 
Terry said:
That washer has a large ID for the pulley to pass through plus it is not flat, the steel material is about 0.023" thick The two washers on the rear of the bearing 10214 & 10098 have smaller ID and neither of them are flat. Having a stepped face helps to keep the felt seals away from the original open face bearing and hold the felt in place. With a sealed bearing there is no need for the felt seals and you can use flat washers of the proper thickness and OD with the ID big enough to clear the pulley.
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Thanks.


Found some wave washers of the correct dimensions on eBay that I'll use on the forward end of the shaft. They're really thin, I'll just build up until it seems like a good fit. Since they're wave washers it's hard to say what the right thickness would be. Unfortunately, the diagram I'm using isn't for my 1941(?) generator. The only one I could find was in the 42-48 shop manual.The 10214 and 10098 don't look like anything I have.
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cmbrucew said:
Use a long screwdriver as a steckastrope.


You beat me to it, I was going to say that. That's what we did at work, we had a long wooden handled screwdriver we used to listen to rotating parts with to find noises. We also had a stethoscope with a metal probe, but I think the screwdriver worked better. Sometimes it is hard to tell where the noise is coming from because it travels through everything. Then you need take the belt off and spin the parts. That doesn't always work because the noise or rough feeling bearing may not be there without the pressure of the belt on it. Check for any play in the water pumps or generator.

I had a guy tell me he could not keep rear bushings in his generator, so he switched the rear generator cover to what he said was a '53 with a rear bearing and he never had a problem again. Maybe he was tightening the belt too much. Every belt has a tension rating and there is a tool for checking it. Too lose and it slips, too tight and it wipes out bearing and bushings. All the old-time shops had that tool, we had one at work and I never did see anybody use it. I'm guilty of it too. We went by feel, how much deflection the belt had between the pulleys. I had a couple '57 T-bird generators and I got to looking at them and the cover was the same size as the flathead, and it had the bearing, but it had mount on it so I cut it off. I figured running a generator mounted fan that it would be best to have a bearing in the front and back of the generator and I then I wouldn't need to be lubricating the rear bushing. That's on a hot rod, with a restored car you have to stay with what it came with. I guess you could drill the rear cover and put a fake lubrication fitting on there.
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Ken/Alabama said:
That wide belt doesn’t need a lot of tension so don’t over tighten it. I’d pull the generator apart and check if the armature is rubbing the pole shoes.
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Added the washers above to stop the fore-aft movement, loosened the belt a bit. Each seemed to help a little. It's quieter now. Might leave it a while.
 
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