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Generator or water pump noise?

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TulsaFred

TulsaFred

Jedi Warrior
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Just about a hundred miles on the rebuilt 1275. Today suddenly began an intermittent terrible noise/vibration. Sounds like either the water pump, or more likely the generator (I've got a bugeye style tach drive gen). A groaning sound with harsh vibration, only when revved a bit, not at idle. When I put my hand on the generator I suspect that is the source, but since the vibration transmits it's hard to say for sure.

So is this a common mode of failure? Rebuild or replace?

thanks for any help

Fred
 
Loosen the belt and see if you can detect any angular play or excessive end float by manipulating the generator pulley. Water pumps typically leak of they are going bad, but you might feel for some excessive play there as well. Didn't you put on a new one with your rebuild? With new ones costing only around $30, I replace them as a matter of course if there's any question of age or wear; not worth the time to have to pull apart once it's in the car.
 
Fred,
Gerard X2...break out your stethoscope and listen to each component to track down the sound.
Rut
 
Rut said:
Fred,
Gerard X2...break out your stethoscope and listen to each component to track down the sound.
Rut
Click to expand...

Translate that stethoscope to....piece of heater hose if your shop is equipped like mine!:smile-new: If its your gen bearings the tach drive gen is like gold. Carefully replace the bearings...not hard....and run your fan belt LOOSE!

Kurt.
 
Disconnect the tach gearbox to eliminate that as a source of the noise.....weakest link in the chain I have found.
Scott in CA
 
What is the acceptable amount of play in the belt? I was always taught to keep the belt as tight as possible. I also have a sound that I'm pretty sure is from the generator as it is dependent on engine revs and not necessarily on car speed or if the clutch is in or out. Mine actually sounds like bearing noise, though.
 
Better be checking bearings as well, Sax Man. I learned the hard way and keep my belts just tight enough to charge. Usually about an inch of easy deflection...no tension at all.

Kurt.
 
I just had this experience myself. I replaced the generator bearing and now there is the sound of silence. My belt had been pulled snug in the past but now there is much less tension and the generator still is charging. Lesson learned.
 
I'm suspecting the generator bearings. Will check when I get back to the shop.
Is replacement a tough job?
 
TulsaFred said:
I'm suspecting the generator bearings. Will check when I get back to the shop.
Is replacement a tough job?
Click to expand...

With a little experience I don't consider it tough. Your brushes will need to be held back on reassembly and the front bearing cover is kinda fragile so will have to be supported when you tap the old beraing out and the new one in. Usually the rear bronze bush is OK and I make no effort to remove the rear housing from the stator housing. The wire's can be fragile.
 
nomad said:
With a little experience I don't consider it tough. Your brushes will need to be held back on reassembly and the front bearing cover is kinda fragile so will have to be supported when you tap the old beraing out and the new one in. Usually the rear bronze bush is OK and I make no effort to remove the rear housing from the stator housing. The wire's can be fragile.
Click to expand...

Oh and mark the housings before disassembly so they are easy to get lined up again.
 
Pulled the generator and removed belt. Sound is gone.
The bearings don't seem obviously bad - no apparent excessive end float or side play. When I rotate the pulley there is a slight sense of a mild grind or rub. Not sure if that's abnormal.
I guess I'll buy another generator with tach drive - $189 at Moss.
 
TulsaFred said:
Pulled the generator and removed belt. Sound is gone.
The bearings don't seem obviously bad - no apparent excessive end float or side play. When I rotate the pulley there is a slight sense of a mild grind or rub. Not sure if that's abnormal.
I guess I'll buy another generator with tach drive - $189 at Moss.
Click to expand...

I'm not sure why you'd need another tach drive unless yours is a re-pop and worn out. The reproductions aren't made near as well as the originals, and don't last very long, so if yours is an original, hang onto it. The bearing in the generator is pretty easy to refit as I recall too.
 
I'm sure my generator bearing is fried, too, given how long I've been driving with tight belts. I have a spare generator that I got with the car that I believe is in need of a rebuild. I may swap the generators just to see if it at least has a better bearing.

I did get the bearing to quiet down somewhat with a couple drops of lube. I'm wondering if shooting some dry lube like graphite into the bearing may help as a temporary fix, too.
 
$189 and if its like the one the PO of my BE fitted its nowhere near the quality of the original. The one I've got has a spigot glued into the back of a regular Lucas generator for the tach drive fitting. The spigot came loose and I reglued it with JB weld and its holding for now. I've got a couple of the original tach drive generators but both need a rebuild. I'd sure try replacing the noisy bearing...what ever you do don't exchange it for one like I'm currently using.

Kurt.
 
Who does a quality rebuild of an origin generator?
 
I know there is a local auto electric shop up in Frederick, Maryland (can't remember the name) that rebuilds vintage stuff like LBC starters and generators. I'll have to go dig up the name.
 
I loosened the belt and put a couple drops of oil in the generator. Things were quiet briefly, but then the bearing noise returned. The one thing I did notice was where my generator light would start to glow right at 1000 RPM before the belt was loosened, it's not coming on until below 1000 RPM, which seems to be telling me the generator is spinning more freely now that tension has been released. After driving with the belt tight for the last two seasons, I'm sure the bearing is toast.
 
Several years ago now I had a generator rebuilt by the local parts stores main supplier of rebuilds. At that time they were done by a Canadian firm by the name of Wilson. Don't know if they are around anymore but I would bet they could rewind one. As to the bearing replacement, I would think, if you don't want to do the job yourself, any good auto repair shop should be able to replace the bearings.

Kurt.
 
A bit of an update. When I drove the car home, it was about 20 degrees warmer than the morning. The bearing was noticeably quieter. I'm still pretty sure it's toast, but not nearly as nail-on-the-chalkboard sounding as it was before. I'm just debating whether I want to swap in the spare first...but still fix the bearing either way. The spare is out of a '67, IIRC, not that would make any difference so long as they are both negative ground. I'm getting close to taking Baby Blue off the road for winter maintenance, but the above-average temperatures we've been having is delaying the process. Last winter, Baby Blue was off the road by the third week of November.
 
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