I am looking to put an extra ground wire or two on my '26 Roadster. (It's a long, long story, but I've tried to get the charging system to work - or at least show that it's working.) This car came to me with what appears to be a 10 gauge wire connecting from the starter to the body frame. Right or wrong it seems to crank over quite well. I want to put a ground from the hogshead to one of the bolts that holds the parking brake equalizer on. I would also like to put a ground somewhere near the generator/alternator (whichever I end up with) to the other side parking brake equalizer bolt. (yes, it does seem overkill) I thought about #1, but is that way too big?
Extra Ground
- Thread starter CatMan1
- Start date
39portlander
Well-known member
Cat, man you can never have to many grounds period. On my 26 I have my ground from the battery to the frame, off that bolt through the frame I have wires to the motor/cab and other side of the passenger frame rail.
#10 should be fine, good grounds will always wake up a starting system. Mostly, have a battery disconnect when parked
Let me add...use a good 6v battery, the Optima I have has made all the difference when starting my T. Good luck and let us know how your wiring project works.
#10 should be fine, good grounds will always wake up a starting system. Mostly, have a battery disconnect when parked
Let me add...use a good 6v battery, the Optima I have has made all the difference when starting my T. Good luck and let us know how your wiring project works.
Cat, man you can never have to many grounds period. On my 26 I have my ground from the battery to the frame, off that bolt through the frame I have wires to the motor/cab and other side of the passenger frame rail.
#10 should be fine, good grounds will always wake up a starting system. Mostly, have a battery disconnect when parked
Let me add...use a good 6v battery, the Optima I have has made all the difference when starting my T. Good luck and let us know how your wiring project works.
I'm going to try that this weekend. The generator is way on the other side of the car compared to where the battery grounds so an extra ground does make sense. I have a 6v Optima battery so starting is never an issue - just charging.
redmodelt
Well-known member
There really is no need for extra grounds. The engine is grounded to the frame in more than 3 places. At the transmission both sides, front motor mount, through the driveshaft to rear end/springs/frame. Any of which, unless paint is too thick or rust is too thick should provide more than adequate grounding. It you are having charging issues, that is maybe more a system needs attention than maybe a ground issue. When was the last time the generator was serviced? Have you check the output?
Adding extra ground wire should be mounted between two points that are stationary, not a moving equalizer.
Adding extra ground wire should be mounted between two points that are stationary, not a moving equalizer.
rotorwrench
Well-known member
The 3-brush generator needs a good battery for voltage control since that is the only voltage control for the type unless it has a modern regulator cut out. The cut out needs to be functional for the generator to come on line. The generator may need to be checked out to see if it needs repairs or overhaul. All normal electrical connections from the generator to the ammeter and back to the battery need to be clean and tight. The ground path is also important but it's not the only possibility when problems arise.
This has been an ongoing situation since June. This car is an older (70's-80's) restoration. It started when I realized that the Ammeter was wired backwards. After I corrected that it will only show a 'Discharge' or '0' and never a 'Charge'. I checked the generator via the instructions provided by Henry Ford. I have since bought a voltage meter. Truthfully I've checked so many things I can't recall them all. The wiring diagrams show that the wires are hooked up right. There is continuity as there should be. I've been through 2 generators, a cutout, a voltage regulator and now an alternator. Nothing will show a 'Charge' on the ammeter and when I use a volt meter at the alternator and at the battery with the car running it only shows around 5.9 -6.0 volts. In August I contacted Birdhaven where I bought the alternator and he came and got it, put it on his tester and it was putting out over 7.0 volts. So far he hasn't brought it back to me..... My next step is to replace EVERYTHING that makes electricity, carries electricity, or stores it. (either that or I'll just sell the car) Sorry, didn't mean to make this long. I've had many other old cars and have a Model A that I bought last year. This T has me stumped! The reason I am asking about the ground wire is that Bill from Birdhaven suggested it to me. The car cranks over just fine via the starter.
rotorwrench
Well-known member
Is the ammeter a modern reproduction or is it and old original? The ammeter should show mid position with no loads on the car. It should show a good amount discharge when the lights are turned on with engine off. It can be tested with a battery charger to see if it will show a charge. Just remember that it is always connected in series unlike a volt meter that is always connected in parallel so it can be placed in the negative side of the charger to battery lead and jumper from the other ammeter terminal back to the negative post. Depending on how it is connected, it can show charge or discharge but it will show the same amp reading as the one on the charger itself. If it works correctly then that component would be eliminated as being non-functional.
An alternator works in a different way than a generator but it will show a charge reading after the car is started until the battery is back to a fully charged state. It may only show a needles width of charge with just the ignition system running on battery. On magneto, it may show no charge reading at all once the battery is back to a charged state. This is due to the internal regulator in the alternator. It only charges when it senses a need to charge. The voltage runs higher with a 6-volt converted alternator running. It can read as high as 7.8-volts. This is one thing I don't like about the modern 6-volt alternators is that the voltage is set too high in the internal regulator but it can't be adjusted. It's just the way they are made.
If you run a 3-brush generator with a Fun Projects regulator installed, it works in similar fashion to the alternator (Bird Haven and John Regan made these for some time). In either case, a volt meter is going to be the only way you will know if it's charging unless the lights are turned on. A person should see a charge with the lights on but it may not be much on the meter since the alternator internal controller automatically adjusts for the current draw as long as the third brush is adjusted per the instructions.
An alternator works in a different way than a generator but it will show a charge reading after the car is started until the battery is back to a fully charged state. It may only show a needles width of charge with just the ignition system running on battery. On magneto, it may show no charge reading at all once the battery is back to a charged state. This is due to the internal regulator in the alternator. It only charges when it senses a need to charge. The voltage runs higher with a 6-volt converted alternator running. It can read as high as 7.8-volts. This is one thing I don't like about the modern 6-volt alternators is that the voltage is set too high in the internal regulator but it can't be adjusted. It's just the way they are made.
If you run a 3-brush generator with a Fun Projects regulator installed, it works in similar fashion to the alternator (Bird Haven and John Regan made these for some time). In either case, a volt meter is going to be the only way you will know if it's charging unless the lights are turned on. A person should see a charge with the lights on but it may not be much on the meter since the alternator internal controller automatically adjusts for the current draw as long as the third brush is adjusted per the instructions.
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The ammeter is a newer reproduction. I plan to replace it, too. I don't want to just go about changing parts and not learning, but I feel it's come to that. Possibly. I'm just used to all the other old cars I've had.....With a load (lights) on the battery the ammeter will show 'discharge'. With the engine revved up enough the ammeter will show 'charge'. As a side note....the mag is dead, too. I doubt that would effect the charging system, though. I have tested it with a light bulb tester (no light) and also had the post out and it looked good.
rotorwrench
Well-known member
The magnets may need to be remagnatised. Residual magnetism will last a long time but does slowly dissipate. The magneto coil plate may need overhaul too.
redmodelt
Well-known member
At an RPM equal to about 20 MPH with the lights on, the meter could be anywhere from -1 to +1 volts if output is set to about 6 amp at same RPM with them off. This is normal.
All this and not one word if you have checked the battery. Maybe it's bad. Even a new battery can be bad or go bad shortly after buying and without know its condition.
All this and not one word if you have checked the battery. Maybe it's bad. Even a new battery can be bad or go bad shortly after buying and without know its condition.
I have checked the battery as best as I can with what tools I have. If I recall correctly it was at one point around 5.92 and that was with the engine running. I don't think it ever got or 6 volts. I have had it on a charger and the charger would not shut off after a few hours. So, this brings me to another question. Is it possible for a battery (an Optima 6v in this case) to be bad so as to not allow charging, but to start the car every time?
rotorwrench
Well-known member
Any 6-volt battery should be 6.1 to 6.3 volts fully charged depending on age and condition. The Optima may have spiral wound glass mat lead matrix instead of flat plates but it still should be very close to 2.1-volts per cell. If it won't charge back up to full voltage then it has lost some of it's capability. Due to the way the spiral cells are made, they have more actual plate area but they can still deteriorate or sulfate just like any other AGM or wet cell battery. The model T has a relatively low compression engine so it doesn't take all that much cranking amps to start one. At that low a voltage, it likely wouldn't turn over very long if the engine was hard to start. It is certainly possible for the battery to be going south but still start the engine.
redmodelt
Well-known member
Leaving the amp meter out, you say you have been replacing parts, 2 generators and several different cut-outs etc. How many of those parts were new/tested/known to be working? Did you ever check the output voltage at the terminal of the generator and compare to the meter reading?
Just saying that the meter showed on the - or + side, not much to go on. What were/are the actual readings? At a high idle RPM, no lights, what does the meter read, either on the dash or at the terminal on the generator now?
Could be with all the swapping around, that the current generator needs the 3rd brush adjusted or was not correctly setup in the first place if it has been taken apart, or needs to be flashed to get it going.
Just swapping the leads on the meter should not have caused any of this.
Maybe, put everything back as it was before all this started except the leads on the meter and go from there. Right now it sounds like you are swapping parts without really knowing what the problem is.
If you get a reading at the generator terminal but show - on the dash meter, good bet the cutout is gone bad. Do you show battery voltage one the battery side of the cutout? You should at all times unless something up stream from there is burnt out or not hooked up right.
Just saying that the meter showed on the - or + side, not much to go on. What were/are the actual readings? At a high idle RPM, no lights, what does the meter read, either on the dash or at the terminal on the generator now?
Could be with all the swapping around, that the current generator needs the 3rd brush adjusted or was not correctly setup in the first place if it has been taken apart, or needs to be flashed to get it going.
Just swapping the leads on the meter should not have caused any of this.
Maybe, put everything back as it was before all this started except the leads on the meter and go from there. Right now it sounds like you are swapping parts without really knowing what the problem is.
If you get a reading at the generator terminal but show - on the dash meter, good bet the cutout is gone bad. Do you show battery voltage one the battery side of the cutout? You should at all times unless something up stream from there is burnt out or not hooked up right.
I haven't replaced much yet, but plan to. Somewhere I have my notes where I've written everything down. There has been so much I can't recall it all right now. Sorry. The generator/cutout setup that the car came with didn't appear to be working as I tested it (without having a voltmeter) like in the Model T book. I bought a rebuilt generator/VR setup and I believe it may have briefly worked as I was adjusting the third brush then quit charging. I don't recall how I tested it. I think I did with a test light to ground. Not the right way, but what I had at the time. Birdhaven warrantied that generator and supplied me with a new 6v alternator. I put it on and it never showed charge. I even revved the engine halfway down the throttle and drove the car. The Birdhaven guy came and got the alternator and tested it, texted me a picture of it putting out 7+ volts. He still hasn't brought it back to me and that was August. I even had a Model T guy from another state drive over and it stumped him.
I wish I could remember now the actual readings. It's been a month since I checked and I thought I had them written down. With the lights on, driving or sitting and engine revved up the ammeter shows discharge.
Tonight I hope to take the battery out and take it to the parts store and have it tested. I also am going to put in some extra grounds. I have a new switch coming. I also have a new Ammeter. I've checked all the wires and they are lined up right and the guy that stopped by agreed. There is full continuity to all of them. Also, although probably not an official test, I also had it running once and disconnected the battery and the engine died as if it was relying on the battery and not benefiting from the alternator.