I need help with my generator problem. On the 4th of July while driving from Dunbarton, NH to Haverhill, Mass I noticed that my ammeter was charging about 10 and then it stopped (staying at zero). I have been reading up on this and have read that a bad cutout can cause this. I bought a new cutout from Lang's and installed it earlier this week but still the generator is not showing a charge on the ammeter, it shows a normal discharge when I turn my lights on. One suggestion was to "Flashing the Generator. If a generator is in good condition but fails to produce an output, it may need to be “flashed”. As I am running a High volume intake manifold and would have to remove that in order to take the generator out, is it a good idea to try flashing the generator first?
Thanks for your help and Happy motoring,
You should not have to take the HV intake manifold off to remove the generator. I am running that manifold on two of my cars and I'm able to remove and replace the generator. It is easier to tip the back of the generator down and remove it from below. That's how I do it and there seems to be plenty of room.
Sorry, I can't answer your question about flashing it. I wouldn't think that would be the problem though. As I understand it, that only has to be done once. I don't think just running it would cause it to lose its polarity.
If it just quit suddenly, I don't think flashing it is gonna help. Could be as simple as a worn brush, but could could be more serious. I'd get the mtfca book on the electrical system. I think that's the one with generator rebuild instructions.
Yes, The Electrical System has twelve pages on the generator. I used it to replace a broken insulator. I'm not great with electrical stuff, but this ain't rocket surgery.
If the circuit between the genny and the battery goes open-circuited long enough, the genny will destroy itself ... $$$ ... You had better find out what's wrong before operating it any more.
You drive your coupe quite a lot. The generator's commutator does get dirty with normal use and can become so dirty that no voltage will be produced. Slide off the cover band and take a look. If it is not clean and shiney wash it off with carb or brake cleaner. Start the engine and then clean the commutator with an eraser; one of those wide pink ones we used in elementary school. Do not use emery cloth or sandpaper as you only want to remove dirt, not copper!
You could have a fault in the generator, but start with the simple things. I have to clean mine every now and then. Good luck with your project. Bill
The amazing thing to me is how often generators are NOT seriously damaged by the things that can so easily destroy them. The odds are good that only a minor repair or refurbish will be needed.
The first best thing to do is with the engine idling, check with a volt meter at the place before the cutout whether or not the generator is producing reasonable electricity (about 8 volts). Under five volts likely means part of the armature has failed. Seven to eight volts before the cutout and nothing after the cutout means that simply the cutout has failed and likely a new cutout (or better yet Fun Projects regulator) alone will have it working again.
Low or no voltage before the cutout means the generator likely will need to be taken out and apart.
Ten amps charge is too much. It can make the armature run hot enough to soften the solder and throw it out of the armature connections. That may or may not ruin the armature. Too high a charging rate can also boil the water out of the battery, which can lead to other problems (possibly even a battery explosion).
Drive carefully, and enjoy, W2
Check the simple things first. Clean the armature with some emory cloth or sand paper. Then check each brush to make sure that they are not worn out. If they are they will be sitting deep into the brush holders. If all this is ok, check the voltage at the generator side of the cut out, with the engine running, whether it be a diode cutout or a mechanical cutout. There should be about 7 volts there. if there is none the generator is shot. A simple check for the generator on the bench is to apply 6 volts between the Generator terminal and case. The Generator should motor. If it does not it is bad. The first thing to check on the generator is to make sure that the Generator terminal is not shorted to the case. If it is you will see immediate sparks when you apply 6 volts.
Thank you to all for your helpful suggestions. I will have to invest in a volt meter. I have used a standard garage test light ( looks like an ice pick on one end and a wire which clips to ground on the other. On the wire end I get a bright light (with car running or not), on the other end I get a very dim, barely noticeable red light. Hope this helps with your thought process.
Warren, once you get everything working again I'd recommend the Fun Projects voltage regulator. If anything causes the generator to be disconnected from the battery, it sacrifices itself to save the generator. Good insurance in my opinion.