Help! It's a 1956 Cadillac Coupe Deville. 365 ci engine. I replaced the Solenoid, battery cables, Voltage regulator and just today the condenser. When I recieved the car the Generator light was not on but I was told by the inspector the voltage regulator was putting out 16 amps and would fry the battery. So I replaced it without thinking. So anyways, I have the car on a trickle charge right now because the generator is not powering up the battery. Every time I drive the car to test it the Gen light stays on and the engine is eating the juice in my battery. I have yet to use the multimeter to find out what the issue is. It just makes me wonder why it wasn't on before I switched out the parts and now it's on with the new parts? I even put in the old Voltage regulator to see if that would make it go off and it didn't make a difference. I will start the trouble shooting that's in the shop manuel tomorrow. Can anyone offer me a suggestion?
POLARIZING YOUR GENERATOR Did you know that your generator can deliver current for either a positive or a negative ground system? Well, it can. And you can make it work in either mode. But, if yours produces current with the wrong polarity, you might have to make costly repairs. A generator produces current by passing conductors (the armature windings) through a magnetic field. The magnetic field is produced by electromagnets that surround the armature. Basically, the field portion of your generator consists of copper windings around iron core, often referred to as the pole shoes. The voltage and current delivered by your generator is determined by the strength of the magnetic field and the speed at which the generator is running. But, the polarity of the current is determined by the polarity of the pole shoes, or the direction of the magnetic flux or field, which is determined by the direction of current through the field windings. OK, so you install a generator and take great care to connect the wires properly so you won't burn out your ammeter or cutout relay. What could go wrong if the wires are hooked up right? Plenty! When you start your engine, the generator will start delivering current. Since the generator is still isolated from the electrical system by the voltage regulator or cutout relay at this point, it will start producing current based on the polarity of the pole shoes. As soon as it begins producing current, some of that current will be directed to the field windings to strengthen the magnetic flux. According to John Deere's Fundamentals of Service manual manual, if the generator polarity is reversed, the generator will build up voltage and close the cutout relay points. This put the generator in series with the battery, and their voltages are added together. This high voltage across the points (about twice the battery voltage) can cause high current and enough heat to weld the points together. This damage does not happen immediately. The instant the points close, the voltage is about the same on both sides of the relay coil, so very little current flows, and spring tension reopens the points. But, generator voltage will again close the points, and the cycle will repeat at a rapid rate. Heat and arcing will finally weld the points together. When the points weld, the battery and generator are connected at all times. The low resistance of the generator allows the battery to continue to discharge through the generator. The high current can create enough heat to burn the armature. How do you control the polarity of the pole shoes? The polarity is determined by the direction of the last current through the field windings. Since even a very small current can polarize the shoes, never assume the generator is properly polarized. You must polarize the generator every time it is disconnected or serviced. To polarize the generator, simply make a short jumper wire to short between the battery (b or bat) and generator (g or gen) lugs on the cutout relay or voltage regulator. Only a split-second or a spark is required, so simply tap your jumper wire onto the lugs and pull them right back off.
Look for a bad terminal or wire breaking down at the regulator. Taking the connector apart could have caused an old wire to give up.
also check to see if the points in your regulator are ok or not before you do this so your not wasting your time..
I think your inspector A= ment 16 volts or B= didn't know shit. And by the way why was he even checking the gen output ????
I will try to Polarize the generator tomorrow, I have never done that before and didn't know that I had to. Are you saying this because I detached the generator from the Solenoid and when I broke all teh connections between the Gen and the Battery that could have screwed up the polarization? I'll investigate that. Thank you! The regulator is brand new, You think I should open it up and check it out? The shop manuel has many touble shooting options for the VOltage regulator. I hate electrical.
wouldnt hurt to check it out (regulator) and it wouldnt hurt to be sure the polarization is correct..just removes those possiblities from the equasion
Yes 16 volts, I said that wrong, I think he was checking the voltage regulator because they were having a problem getting the car started and were unaware that all they had to do was knock the solenoid and it would turn over really easily.
Ok, I made the jumper and got the regulartor to spark a couple times actually I did it three or four times. The Generator light stayed on. So the polorizing wasn't the issue. Then I used the Multimeter and checked current and volts. All the lines are passing current. My Multimeter said that the voltage regulator was sending 18 volts to the batt. While when I checked at the regulator to see how many volts the Generator was producung it said less than two volts. That doesn't make any sense at all. I'm going to do a little more testing and see if I can't figure this out. I'm thinking of having the generator tested.
well at least you ruled out the polarizing issue.. what you describe sure seems odd...Ill have to think about this one 18 volts eh...12+6..humm?..and you say 2 at the generator..shit ..got me scratching my head..any one else?
Also, I just had the same problem on my 60 pu... generator looked fine and still had gloss black paint on it. Pop took it apart and cleaned it up a bit with some still wool. Reinstalled it and it was fine. I also had the one on my 59 olds go bad, had it rebuilt though!
Yep check for continunty on both wires reg to gen. Small wire to field terminal both ends,larger one to bat or arm terminal however marked.Also some times there was a 3rd wire from base of reg to body of gen. You are taking your volt reading off the large terminal on the gen with the engine running over 1000 rpm aren't you? No way you can get 16 volts if the gen has no output, meter good?
I have been looking on line for some solutions along with the Shop manuel. I'll let you know what I figure out. The Ohms meter says all my lines are passing current. So the wires are alright. The one thing I am questioning is maybe my method of polarizing was wrong? I made the sparks between the "Batt" and the "ARM". That's correct right? I didn't rev the engine and get the RPM's up but maybe I'll give it a shot at lunch tomorrow and see if it's just a case of me not following directions carefully. I haven't touched the "Field" contact, I think I'm supposed to avoid that. I was reading a page in the internet that said : 11. After all leads are reconnected and before the engine is started, the generator should be polarized by momentarily connecting a jumper wire between the “GEN” and “BATT” terminal of theregulator. Just a touch of the jumper to both terminal is all that is required. The contradiction: To polarize an “A” circuit charging system you can use your jumper wire. First connect one end to the field terminal of the regulator. Now strike the “BATT” terminal with the other end. Once or twice will do, just until you see a few sparks at the terminal. That’s it, you’re done! (FYI: GM products typically used “A” circuit charging systems.) I guess I just have to keep monkeying with it till I figure it out. Uhg!
My next step is taking down the generator and cleaning it up, going over all my connections again, Polarizing and then go to Church on Sunday.
last time I polarized, it took a good 5 seconds with the a screw driver to get the gen to spit out some good juice. Just a thought while your scratching.....
From all the posts my reasoning is like this: 1) You have no way of getting 18V at the battery (like someone else pointed out). Make sure your meter works correctly on another known good battery and that you are using the proper scale if the meter is an analog type meter. (Digital meter won't lie unless it's defective or it's battery is low. 2) Once you read the proper voltage at the battery (12V or so) then the next thing to check is the voltage regulator and generator. This is easily accomplished by disconnecting the small FIELD wire at the voltage regulator. Then start engine and ground the small FIELD wire to a known good ground (regulator base s/b ok.) If the generator light goes off then the generator is ok, if not the voltage regulator is bad or the generator field winding is open. By grounding the FIELD wire you have bypassed the regulator and have the generator producing it's maximum output. But this is only true if the field winding is ok in the generator. The armature maybe be bad too but if so it is shorted because the generator light uses armature for the ground return. Try the FIELD WIRE TRICK and let us know the results.
you need to check that your regulator is properly grounded. it should have a seperate ground wire at the base of the case. a poorly grounded regulator will not operate correctly and could cause the overcharge condition you are having. bad grounds will play hell with your electrical system and your head.
Also realize a little over 15V isn't uncommon if the car's been sitting a while and has a low battery. Look at the volt gauge on car that's just been jump started. Recheck all your connections and the case mounting, it probably grounds thru the mounting bolts. If it doesn't work, throw the old one back on and see what happens. If the car runs fine, you bought a defective component. If the light's still on, you've got a bad wire or a polarization issue. good luck
Just wanted to say thanks, I the Generator kissed off after I started testing it. I tested it individually and discovered it is putting out no juice. Problem solved . I'll try and get a tougher one next time. That one was too easy. It just sucks I wasted so much time scratching me head wondering what the hell was wrong. I thought I was losing me mind! I'm just glad it was a simple solution. Thanks HAMBERS for all the help and suggestions!!!
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