Hoping the power of the HAMB can help. I have a 60 Ford F100, 292 and 3 on the tree that is my parts chaser and hauler. Everything is pretty much stock on it. I've been driving it last fall and this spring and doing maintenance and tune ups as I go. Currently, the GEN light is staying on all of the time, and I don't seem to be getting any charge when I test with a voltmeter. I'll outline the events leading up to the problem, and my troubleshooting so far: Last weekend, I used it to haul some stuff and move a bunch of furniture for my buddy. On the Friday, when I left it was running fine. On my way down to pick up an engine I ran into a pretty good rainstorm. Ended up driving in the rain for 3 or 4 hours. Towards the end of the day in the rain, I noticed that when leaving from a stop, my GEN light would stay on a little longer than normal. I thought with all of the rain, the belt might have been slipping slightly. Other than that, the truck was running and starting fine. Saturday, I made the move. Got caught in stop and go traffic for about a half hour, and otherwise drove for an hour with no problems. The GEN light stayed on during most of the stop and go (which I expected). Once I got on the highway, it wasn't until I got up around 35 or 40 MPH that the GEN light went out. Sunday, I had to head for home. The entire drive (most of it at 50 MPH) the light stayed on. - I've checked the belt to make sure it wasn't slipping. It's tight, and with the motor running, I can't see or hear any slippage when looking under the hood. - Checked all wires leading from the regulator to the generator. I don't see any breaks in the wires, and I crimped new ends on at the generator and regulator to ensure good connections. - Removed the generator and checked the brushes. The brushes have plenty of life left in them, and the springs are working as they should. - Polarized the generator as advised by quickly jumping the BAT and FLD terminals. A spark, and that's it. - Swapped regulators. I had a spare regulator that came out of the 34. I hooked the wires up just to test. The only difference between the two seemed to be that if I pressed the toggle closed on the BAT connection, it would spark and then stay closed. Leaving it open and then starting the truck didn't make it snap closed, and didn't cause the GEN light to turn off. (The regulator currently in the truck doesn't spark when I close the connection, and it doesn't stay closed unless I hold it). Both regulators are very clean and have no dirt or corrosion build up. I have my wires hooked up to the regulator in the following order: Wire coming off the brush post to the ARM terminal. Wire coming off the field (?) post on the generator to the FLD terminal. Wire coming off the ground (?) post on the generator to ground. Wire coming from the starter relay to the BAT terminal. There is a second wire hooked to the ARM terminal that feeds into the wiring harness. It looks like to goes to the GEN light. This is how the wires were hooked up when I got the truck, and the generator was charging fine until now. I'm wondering if my generator needs a rebuild. Or if both my regulators are toast. Any suggestions and advice would be greatly appreciated. I plan to stay with the generator (even if it needs to be rebuilt), so the "switch to an alternator" comments need not apply. Thanks in advance!
Not to be a dick..... Did ya put a voltmeter on it to see what's going on? You did a hell of a lot if work not to do that first!
I ran a voltmeter across the battery with the engine off. Got roughly 11.9 volts. Minimal change (range of 11.9-12.4) across the battery with the engine running, either at idle, or above idle. That's why I checked the brushes and tested another regulator.
Test the generator with all wires removed. Put a voltmeter to the output terminal. Now run the engine at least 1500-1800 rpm, then energize the field just long enough to see if the volts go way, way beyond specs. i use analog voltmeter for this test, but I suppose a digital will work. An analog is easier as you would see the needle quickly go way past 20v+. digital might be random hunting? If the gen does run wild, then it could be wiring or regulator.
F&J hit one good point when he said test it at 1500/1800 rpm. Generators don't usually start getting any real output until you get up to that speed. While you can easily jump a car with an alternator and let it idle for a while and charge up the battery it won't work on a vehicle with a generator. It has to have road speed to charge right. If you have the lights and or radio on and are stuck in traffic the draw from the lights and or radio can easily be more than what the generator is putting out. Throw the electric wipers into the mix and you have even more draw. Once you check it at the 1500/1800 rpm if it doesn't put out a reasonable charge (14.2 would be perfect but 13.5 should work) I'd take the generator off and take it to a shop with test equipment to have it thoroughly tested and go from there.
Get a Motors manual and look up generators. It will give you a series of tests to perform and it will direct you in the right direction until you find out what is wrong. All good mechanics had these. No one can remember it all. Ebay has them all the time. I don't worry about condition too much as long as it is still readable.
I've been working in between the rain storms that we've been getting this weekend. All of my testing/voltage readings have been with the motor running above idle. I don't have a tach on the truck, but I know I have the motor spinning at least 1500 rpm when testing. Probably up around 2000 rpm or maybe a little higher depending on who is working the gas for me. Just to make sure I'm on the same page as you... positive voltmeter on the output post. Negative voltmeter on ground. Energize the generator by jumping a wire between the output post and the field post. Correct? I only have a digital voltmeter, but I'm sure I can make it work for what I need.
See my above reply, but all of my tests have been done with the engine spinning at a driving speed. No radio or electric wipers to worry about From what I've read and been told, I'd be looking for 14.2 across the battery if the generator is charging, correct?
I don't have a Motors manual yet. I have been keeping an eye out for one, or for a Ford service manual. However, I have been working with a 1958 Ford service manual, which I expect will give me most all of the same tests for the Generator system. Link to that section of the manual here: http://www.oldcarmanualproject.com/manuals/Ford/1958/Service/08/Group8/index.html
Just to follow up on this problem... It seems that something shorted out and the generator overheated. Got hot enough to start throwing solder out of the armature. There was a perfect little ring of solder around the inside of the generator case. The regulator may have stuck open causing it to overheat. Either way, generator is back in the truck and the battery is currently charging. Thanks to everyone who helped and provided advice!
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