It seems like there has been a lot of discussion about generator issues lately on the forum. I have been reading all this and then Friday, I took the T to work. It's 20 miles one way from Lynchburg to Big Island Va. with plenty of long hills to climb. On the way home, there was an awful squeal coming and going. I made it home , lifted the hood and it was obviously coming from the generator. Mind you it was still charging. The rear bearing sounded bad. I took it off the car and took it apart. The rear bearing fell apart when I pulled the rotor out and there was burned up stuff all over the brush rigging. The front bearing was well on it's way to failure as well. The rotor segments had shifted out of alignment and it looked like some solder had wiped around the outside of the rotor. At first I thought the rotor had rubbed on the pole faces but there were no marks on the pole faces. I took the field windings and pole faces out as well as the brush plate. Everything had to be cleaned and inspected. I went to the place I usually get bearings from but they were closed(Saturday). On the way home I passed by a NAPA store. I had the bearing dimensions and numbers off the old bearings on a piece of paper. I told the guy behind the counter(50ish years old) what I was looking for and handed him the paper. He says, yeah, I got those,walked 10 feet to a metal shelf picked out the bearings and handed them to me. I was out the door with the parts faster than you can go through drive through at McDonald's. I cleaned everything up and found that my insulated big brush holder was shorted to ground. I had another parts generator on hand that I was going to build up as a spare so I had another brush plate, rotor and new brushes. I used the directions from a past thread to set the brush plate and the third brush and at High idle I have 12 amps charge, about 5 amps charge at 20 mph. I have ordered a regulator from Lang's to replace my cut out. I took the T to go buy a temperature gun this morning. Harbor Freight is 5 miles from me with some good hills in between. I went and got the IR gun, rode around the neighbor hood a little and came home. I measured some temperatures in the engine compartment. The top of the generator was 180 F and the sides and rear bearing were 160F. The intake manifold was 200F. The exhaust manifold was 600F on top and at the rear and 500 F on the sides.The head was 185F and the motor meter was at the Normal summer temp. line. It was 90 outside when I did this. The generator temperature seemed high to me. I have always been told that for every 10F above 140 F you cut the life of your grease by 1/2. The new generator bearings are sealed so they can't be re lubricated on the run. What are your experiences with generator temperatures?
I don't know if it's right, but I have taken to leaving the brush cover off to get better cooling to the internals. IMHO, it is easier to remove the grim with a little contact cleaner than rebuilding the gen due to overheating.
Chester, I personally would back off the high amp setting to a max of 10 amps.
12A is way too high. That will cook a generator in no time. With your setting at 5A @ 20mph, it sounds like the third brush is bouncing. A poorly cut commutator, dirt or weak spring can cause this.
Forgot to mention: Your IR Thermometer probably doesn't read high enough to read the exhaust manifold temperature. Your 600°F reading is most likely the maximum it will read. After running, I would expect the manifold to be well over that. Perhaps in the 800-1200°F range.
You should set it to read just about 1 - 2 amps at cruising speed with the headlights on. 12 amps will fry the generator like Ken says.
"it sounds like the third brush is bouncing" is a miss-speak. I should have said just brush bounce. It's actually the Positive brush bouncing that can cause the generator to charge erratically. Sorry for the error.
Seeing solder probably means it has been run open-circuited at some point - it should be sent to an expert repairman or get yourself a properly rebuilt unit for about $300. Don't take it to your local motor-winding repair shop.
Yes, you gotta turn that generator down. Mine runs 5 amps cruising with light off. It runs near zero with the lights on. Perfect when you consider I run with my lights on about 30% of the time or less. You might see a slight discharge with lights on but, this will go away as your battery charges to the right level. You will love the Fun Projects voltage regulator. Best thing I ever did to my car. It will make your car daily driver reliable.
On my 6-volt '24 Touring, I rebuilt my generator, and at 30 mph, the ammeter reads about 15 amps on the dot, but I'm assuming that the old ammeter is not particularly accurate. My Fluke multimeter doesn't read more than 10 amps, so it was difficult to make sure it was set correctly, but I did the best that I could with what I had.
Now out of all the times I have run my T, I have never had an issue with the generator. It gets warm, but no warmer than engine compartment temperature. It has just become one of those parts on my car that I never worry about. It always works perfectly every time.
Running at a constant charge of even 8-10 amps is going to be rough on your battery as well as your generator. I assume you must have measured your ammeter off the car to have used your Fluke meter. 15 amps is absolute maximum peak output of a good generator but never where you should run one if you want it to last. I have never understood why so many folks seem to always think that "more is better" when clearly it just destroys things or hastens their demise. If a T is in decent tune it will easily start in 5 seconds or less with its starter. That amount of charge can be returned to the battery in less than 5 minutes even at a constant charge of only 4 amps. From then on the battery is being abused with overcharge. Think about it. Ford's adjustment procedure was using 20 CP bulbs and was during the T era when the roads didn't allow long sustained high speed driving. Today's roads almost guarantee long high speed drives. Its your car and entirely up to you but it sure doesn't seem logical to me to set a generator so high and leave it there. I can't see what good that could ever do.
I run mine at about 2 to 3 amps with the lights off. I don't even worry about how it charges with them on, because I rarely drive after dark. I try to plan my trips to drive during the daytime and only if I should get caught out later than I had planned do I turn on the lights. If I lived in the city, I might be more inclined to drive after dark, but on these country roads, I don't feel safe putting along at 35 when those who come up behind me are going 55 or faster. I would rather drive during the daytime when they can see me and judge my speed.
My battery seems to stay charged with the 3 amps, and if the car is parked for extended periods I use a charger on it. before I drive.