Generator output too high.

Zephyr4

Zephyr4

Member
I seem to have a later generator with the ribbed aluminium front plate and ventilated rear plate. I've cleaned up and re-adjusted the cut out switch. Finally, I now have current, but it's too high even with the 3rd brush adjusted all the way up. As soon as I'm up to a normal driving speed, the ammeter is reading 15 amps. I've put a voltmeter on the battery and it's reaching 8.3 volts with some rpm, which is higher than recommended I think.

Any suggestions as to my next step?
 
Battery begins to hydrate ("boil") at about 7.8 volts, depending on temperature. I'd think the generator should have a better adjustment range, but apparently it's not for model A. The quick and dirty solution is to run your headlights all the time. But carry lots of spare bulbs.
 
Running that high voltage and amps will likely cause the generator to throw solder and destroy itself. I have no answer to the problem, good luck!
 
It is always worth mentioning to ensure that you have good generator ground. Poor ground can cause an overcharge situation.
 
HI Guys, Zephyr 4 wrote " Finally, I now have current, but it's too high even with the 3rd brush adjusted all the way up " Any other suggestions? Assuming ammeter/voltmeter accurate, I think Badpuppy in #2 is on the right track.
 
Most 6-volt 3-brush generators are set up to only generate around 6.5 to 7.5 volts and some aren't capable of generating more than that. The 3rd brush just adjusts the amperage output between low readings to maximum output. If the ground brush isn't getting a good ground, I don't see how it can get higher output. If anything, it should be lower or intermittent. High resistance = low output.

Considering the OP's location, it may have a 3-brush generator from some other application or UK manufacturer. Ford had specific configurations for their generators and others may have been a bit different in the way the output is controlled. Here in the states there were only two designs of generator used on the model A but I have no idea what they used in the UK from Dagenham. Your generator may be adjusted differently than the types used here in the US. Some are set up to be switched for night time high output and others are not.

This link is to a more general instruction for 3-brush generators that sort of lets you know what differences may be encountered.https://www.yesterdaystractors.com/articles/artint4.htm
Otherwise, the OP will need to identify the unit he has and look for specific instructions for it.
 
Thanks for the replies guys. It's actually a Danish car with the proper 201ci engine and all. The generator was on the car when I got it, but the cut out was only half there and that half was rusty. I had another generator which didn't work, but had a complete cut out. So I cleaned up and adjusted that cut out as per the manual, stuck it on the generator that came with the car (which I found would motor) and suddenly I had electricity. Too much electricity, like 20 amps or so. I adjusted the 3rd brush upwards until it came to what felt like a proper 'stop'. I now read 15 amps and 8.3 volts.

I haven't opened this generator up, but I'll give that a try tonight and see what lurks within.

Pictures speak a thousand words they say: is there a trick to including them on this forum or do they all have to be externally hosted?
 
OOPs, sent previous before I meant to. Additional info displays and click on manage attachments.


Then click on the top browse box and find the picture, click on the picture, and click on the top upload box.


Repeat on the empty browse boxes until you have all pics uploaded.


Then click on bottom of Close Windows box.
 
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