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Just Installed Rebuilt Generator - It's SMOKING?!

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BrandonBJ8

Jedi Trainee
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I just finished installing the generator I had rebuilt. The car started fine and the whirling sound I heard before has been eliminated. I let the car idle for about 1-2 minutes and it ran well. I turned off the car and then noticed smoke coming out of both sides of the generator. It was a moderate amount, but not a huge amount. It smelled electrical. I've since turned off the batery and it has gone away. Is this normal for a newly rebuilt generator? I had the paint stripped and a clear coat put over the metal as well, but I don't think this would effect the internals.

Thanks!
-Brandon
 
Well, I waited a little while and ran the car again and it wasn't smoking anymore. Hopefully it was just a one time thing for the first time it ran since it was rebuilt.
 
Now that it has stopped smoking you might want to check whether or not the generator is putting out any voltage....
 
Well guys, if all the smoke came out upon initial use it don't seem like that Dynamo is any good any more.Probably wasn't any good in the first place---Keoke /ubbthreads/images/graemlins/nonod.gif

OF course Brandon, if you forgot to polarise it initially sometimes they smoke. /ubbthreads/images/graemlins/yesnod.gif
 
Re: Just Installed Rebuilt Generator - It's SMOKIN

[ QUOTE ]
I just finished installing the generator I had rebuilt. The car started fine and the whirling sound I heard before has been eliminated. I let the car idle for about 1-2 minutes and it ran well. I turned off the car and then noticed smoke coming out of both sides of the generator. It was a moderate amount, but not a huge amount. It smelled electrical. I've since turned off the battery and it has gone away. Is this normal for a newly rebuilt generator? I had the paint stripped and a clear coat put over the metal as well, but I don't think this would effect the internals.
Thanks!
-Brandon

[/ QUOTE ]
Hi Brandon,
When you install a new generator it needs to be polarized correctly.To polarize the field, the safest procedure is to lift the D & F wires at the generator. Momentarily connect a wire from the car's battery, starter solenoid hot terminal, to the F terminal for a second or two. Reconnect the wiring. (Engine NOT running for this procedure.) There is a residual magnetism in the generator field poles that gets reversed by this process.

If you do not do this the generator may try to put out the opposite polarity & something gets very hot.

Also, there is a cutout winding & contact in the regulator that is supposed to disconnect the generator when the generator is not charging. (Prevents reverse current) If the generator is not properly polarized, this contact will remain closed when the engine & generator are stopped. This causes the generator to try to act as a motor & turn the engine, which it cannot do. So the generator smokes.

The regulator cutout contact may be welded shut, or the generator may be damaged, or both. Check things out before turning the battery switch on or running the engine.
D
Edit: Too late I guess. Follow Michael's advice & check the generator output. Maybe you were lucky?
D
 
Re: Just Installed Rebuilt Generator - It's SMOKIN

Everything seems to be running fine now. I ran the car again last night for about 5 minutes and it ran great with no smoking. Is it possible for the car to run fine and there still be a problem with the generator?

Thanks
 
Re: Just Installed Rebuilt Generator - It's SMOKIN

[ QUOTE ]
Everything seems to be running fine now. I ran the car again last night for about 5 minutes and it ran great with no smoking. Is it possible for the car to run fine and there still be a problem with the generator?

Thanks

[/ QUOTE ]

Brandon--

Yes, what you really want to find out is whether or not the generator is putting out voltage and if so how much. To begin with, is the charging light located at the bottom of your tach coming on when the key is switched on, then going off when the engine is started and revved up above 1200 or so rpm's? If so, a next easy step would be to test battery voltage both before and after start-up with a multimeter at the battery or control box posts. It should be 12.5 or so volts with the engine off and hopefully above 13.5 volts with engine fast running. I assume you still have the stock control box (voltage regulator) installed--there are very good instructions in the workshop manual as to testing and, if necessary, adjusting the box if need be. If your battery voltage does not go up after starting the engine your generator is likely dead, caused no doubt by the escape of the smoke--maintaining a sufficient smoke level in the charging system is critical.
 
Re: Just Installed Rebuilt Generator - It's SMOKIN

Michael,

The ignition light goes off after the car starts. I just tested the voltage of the battery. With the car off, it was at 12.0. I started the car and reved the engine a bit and it went to 12.4. Then I revved it some more (at around 3k) and it was up to 12.7. Does it sound like everything is okay?

Thanks!
 
Re: Just Installed Rebuilt Generator - It's SMOKIN

[ QUOTE ]
Michael,

The ignition light goes off after the car starts. I just tested the voltage of the battery. With the car off, it was at 12.0. I started the car and reved the engine a bit and it went to 12.4. Then I revved it some more (at around 3k) and it was up to 12.7. Does it sound like everything is okay?

Thanks!

[/ QUOTE ]

Brandon--

A 12 volt battery should be at something over 12.5 volts with no load and ignition off--12.0 is commonly referred to as dead, though it might turn your car over--and definitely over 13 volts with engine running at 1500 rpm's. Why not borrow another meter and test with it before going too far just to verify that the problem is with the car and not the measuring device--most folks recommend using analog meters rather than digital, though I don't know why. If the reading is the same with both meters then you might want to get out your workshop manual and start walking through the section on setting/changing your control box (regulator)cut-in/cut-out settings. I'm no expert here and frankly never had a lot of luck with getting my old generator to be all that it could be, one of the reasons why I switched to an alternator, but the instructions are pretty easy to follow and you might get lucky.
 
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