Noah Posted July 12, 2020 Report Share Posted July 12, 2020 (edited) Hey all, I've got an issue I can't seem to figure out. Seems pretty odd to me and I can't even make sense of why it would happen. Motor is a 218CI Flathead six out of a '49 plymouth. It's installed in a '57 Dodge D100 pickup. The engine started running a bit rough, a bit of a sputter, when accelerating. Also, it did not want to start hot, wait 15-20 minutes and starts. The ammeter was broken and the battery died so I went ahead and replaced the ammeter, battery, generator (yes, I polarized it) , voltage regulator, coil, fuel pump, added a couple ground straps, reset the breaker points. I fired it up and it ran fine for about two miles, then almost instantly it started sputtering. When it was running fine it did not show a charge so I thought maybe I received a bunk ammeter. When it started sputtering, simultaneously it also started showing a nice charge. I thought it was a coincidence. I took it back to the shop and checked all the grounds, wiring resistance and connections and routing. All looked good. I took it out again and seemed to be running fine so I drove for about 20 minutes putting it through the paces, with no issues, EXCEPT, it's not showing a charge now, showing a slight draw. Finally got on the highway and at top end picked up a slight sputter. While limping back home the sputter got a bit worse. Also, need to mention simultaneously with the sputter returning, the ammeter now shows a charge. I can't place the relationship, anyone have any thoughts? Could it be the distributor? Points? I'm fairly certain it's an electrical issue due to the simultaneous misfires/sputtering aligned with the charge showing on the ammeter. Thanks in advance for taking the time to read this and respond. Located in North San Diego if anyone nearby wants to check it out. Edited July 12, 2020 by Noah More tags Quote Link to comment Share on other sites More sharing options...
nc plumber Posted July 13, 2020 Report Share Posted July 13, 2020 That is an interesting problem. Something is definitely amiss (pun intended) in the electrical system. I would check the voltage to the coil, both when it's showing a discharge and when it's charging. It shouldn't be showing a discharge when it's running , so if you can figure out why, then the other problems are likely to be resolved. I might be tempted to put the old regulator back in as a test. Quote Link to comment Share on other sites More sharing options...
Sniper Posted July 13, 2020 Report Share Posted July 13, 2020 Did you also polarize the regulator? 1 Quote Link to comment Share on other sites More sharing options...
Sam Buchanan Posted July 13, 2020 Report Share Posted July 13, 2020 (edited) Sounds like your ammeter is probably wired backwards. Switch the wires on the two terminals and you should see a slight charge when running and a slight discharge when idling. Is your truck still positive ground? If someone switched it to negative ground they probably didn't change the ammeter wires. I don't have a suggestion for the missing, but it has to be something with fuel delivery or electrical. Is the battery being fulled charged by the generator? Has battery voltage dropped following the misfiring episodes? Check battery voltage after the hiccups and also put a meter across the battery terminals to make sure you are seeing ~7.4v at mid-rpm. If not the battery voltage may be dropping enough to cause the misfires. Edited July 13, 2020 by Sam Buchanan 1 Quote Link to comment Share on other sites More sharing options...
keithb7 Posted July 13, 2020 Report Share Posted July 13, 2020 (edited) I have sometimes found that there can be a couple of things going on at the same time. Causing a few issues. Honing in on one solution can cause us to have tunnel vision. A couple of checks that I have done. Set a digital multimeter in the cab near you. Run longer leads out to the battery terminals. Watch the battery voltage when you first get in the truck. Then start the truck, it should drop some. At idle it won't charge much. Take it for a drive. Watch the battery voltage. It should start climbing as it recharges, eventually going up above 7 volts. The battery voltage should not be dropping while you are at a driving rpm. Stopped at a light, foot on the brake, or headlights on, yes voltage will drop. Rev up and drive away, the battery will re-charge again. The second test I have done is get a clamp style Digital multimeter. I clamp around the output wire from the generator. Set to DC amps I can lean into the engine bay, watch amps coming off the generator. Rev up the throttle and watch amps rise as the battery gets re-charged. As a battery gets closer to a fully charged state, it will not accept more amps. The regulator controls that. When you say all the wiring is good. I assume you looked at all the wires inside the distributor cap? The insulators where the coil wire enter the distributor? All good? No cracks. No possible paths to ground? You said you re-set the points. What's the history on the condenser? When was it last changed? Spark plugs clean and gapped? Distributor cap & rotor has no build up or carbon cracks? Spark plug & coil wires are newer, soft and well seated? Vacuum advance vacuum pot working? Centrifugal advance seem ok? Distributor bushings pretty tight? I could go on, listing things to check. I am not suggesting you throw more parts at it and hope that it makes the problem disappear. I am implying that troubleshooting can be a process of elimination. When you check all the variable things off your list, you will find something is off. I have learned to start with 1 system, say the ignition system. Go through it. Then you know its all good. Then hit the fuel system, throughout. From the tank all the way to the carb venturi. Everything in between including carb settings. Then I'll hit the next system like maybe intake manifold, vacuum leaks, valve seating, compression test etc... Sadly today's new regulators, fuel pumps, vacuum pots, almost everything, is not as reliable as it was at one time. Don't assume the new parts you installed are 100% working as they should. Good luck. Keep at it, you'll get it. Edited July 13, 2020 by keithb7 Quote Link to comment Share on other sites More sharing options...
50mech Posted July 13, 2020 Report Share Posted July 13, 2020 (edited) Have an automatic choke? I'd be suspicious of it grounding out, thus starving the coil for voltage. As well as a backward ammeter. Either way I'd be pretty much certain of backward ammeter and something somewhere grounding out.... possibly heat related ( an intermittent short)...when it does it shows charge... Which is actually discharge and a short that's starving the coil. The intermittent short would also explain why your battery died. Edited July 13, 2020 by 50mech Quote Link to comment Share on other sites More sharing options...
plymouthcranbrook Posted July 13, 2020 Report Share Posted July 13, 2020 (edited) I believe the choke wire on the Factory choke only has power when the starter is engaged. When the wire on my 52 shorted out there was a big cloud of smoke and the motor turned over very slowly. Edited July 13, 2020 by plymouthcranbrook Quote Link to comment Share on other sites More sharing options...
kencombs Posted July 13, 2020 Report Share Posted July 13, 2020 Is this a newer install? As in, has it ever ran correctly? Not sure it makes any difference but your 57 is a 12v, negative ground chassis while the engines' ignition system (coil) is (was) 6v/pos ground. Can we assume that was changed to the correct one for the chassis, not engine? You mentioned problems with starting when hot. Used to see a lot of that and it was usually either the starter needed bushings or poor grounding, either poor connections, bad or undersized cables. I'd recommend revisiting all the connections looking for loose connectors, defective wire to terminal crimps, broken strands etc. Quote Link to comment Share on other sites More sharing options...
soth122003 Posted July 13, 2020 Report Share Posted July 13, 2020 Check the generator. Had the same problem one time and it was both the Voltage Regulator and the Generator. The VR was shot and the genny had a bad armature. Since you said you replaced the VR check the genny for voltage output and amperage. Motors manual and your shop manual will tell you how to check your genny. Joe Lee Quote Link to comment Share on other sites More sharing options...
Noah Posted July 14, 2020 Author Report Share Posted July 14, 2020 (edited) Thanks everyone. Looks like I could add a few details. KeithB7 - Not sure how to check centrifugal advance on the distributor, vacuum seems fine although it did seem to be advancing too far, so I added a spacer above the spring, haven't' tried it since. Bushings have some play, I could actually double the gap if I pushed on the rotor. Sniper - I'm fairly sure I did. But the sputtering was happening before and after replacement. Can't say about the charging since I had a bad ammeter. The truck has run fine for almost a year and a half for me. The ammeter was broken when I got it, but since the battery never drained, I didn't worry too much about it. I re-wired the entire truck top to bottom when I got it, no issues for the last year and a half. I took it out a couple weeks ago and that's when it wouldn't start hot. Let it sit for 15 and then it started. This happened a couple times and the battery was dead, so that's when I decided to upgrade the charging system. I replaced the voltage regulator, coil, generator. Plugs and wires are new, sprayed with water and didn't see any sparks. It was sputtering before and after all of the replacements. When it wouldn't start hot, it would crank over fine, just not fire. It seems to not be an issue with the hot start now, I think it may have been the fuel pump or drained battery. As far as the ammeter being wired backwards, I don't think so. It shows a slight discharge when I turn on the headlights, no engine running. It's a big difference when it starts sputtering and goes from a 1-3 amp discharge and then when the engine runs fine it shows maybe 10-15 amp charge. I followed the wiring diagram for the chassis. Field and armature wires go from the generator to the voltage regulator. From the regulator (battery post) to the ammeter, from that same ammeter post it pigtails the headlight switch, then power over to the ignition switch, Ignition switch to coil. The other post of the ammeter goes back to the battery. The truck has a 12v, negative ground and I matched all new components. Only thing I haven't done is the distributor, aside from setting the breaker points. The wire from the coil to the distributor is new and good condition., have not touched the condenser. I took the distributor out and there is some play in the bushings. I could move and double the gap in the points, not sure how much play is acceptable. Distributor cap and rotor all look good. I had thought it may be a grounding issue. Retraced all my wired, checked all connections and nothing out of order that I found. Cleaned grounding cables, added some new ground straps, replaced the a battery cables. I took a couple videos, sorry poor aim while I was driving, goal was to get engine sound but you can see the ammeter as well. These videos were taken 30 seconds apart. Didn't even turn off the camera and it started running smoothly again and like a light switch, no charge. No Sputter No Charge, Look at the last few seconds you can see my foot hit the gas and smooth engine sound. https://drive.google.com/file/d/13oQnxUQDdomeB0IER_IfZ5Y3IgHRojI-/view?usp=sharing Sputter w/ Charge: https://drive.google.com/file/d/13o6JayONsSDNDgsf04ElmQ4gj6w4QecT/view?usp=sharing Edited July 14, 2020 by Noah Quote Link to comment Share on other sites More sharing options...
50mech Posted July 14, 2020 Report Share Posted July 14, 2020 Well, two other possibilities...just thinking out loud. Ammeter shows charge anytime the battery is getting more current than everything else so if everything else is cutting out that could do it. First component I'd think of common to everything else would be the ignition switch. I guess if you wired in a test light you might be able to see if you get a flicker. The other would be something that both shorts out power to your ignition coil and has a connection to the battery side of the ammeter. Horn relay has the potential. Quote Link to comment Share on other sites More sharing options...
kencombs Posted July 14, 2020 Report Share Posted July 14, 2020 11 hours ago, Noah said: Field and armature wires go from the generator to the voltage regulator. From the regulator (battery post) to the ammeter, from that same ammeter post it pigtails the headlight switch, then power over to the ignition switch, Ignition switch to coil. The other post of the ammeter goes back to the battery. The truck has a This sounds like the headlight switch is a key location. a bad connection there could cause the problems. Are these connections serial or parallel? On rereading it, it seems that no current passes thru the ammeter as the load and power source are on the same post. Can you clarify? Quote Link to comment Share on other sites More sharing options...
BobT-47P15 Posted July 14, 2020 Report Share Posted July 14, 2020 One way to get a different, outside opinion is your local generator shop (auto electric place). They deal with such stuff regularly and might be able to do some tests with their equipment. They may charge for their services, but it might possibly determine the problem. I am thinking about visiting my local shop who can test for generator output and other things. I don't have equipment at home for testing. Just my 2 cents worth. Quote Link to comment Share on other sites More sharing options...
Noah Posted July 16, 2020 Author Report Share Posted July 16, 2020 On 7/14/2020 at 6:06 AM, kencombs said: This sounds like the headlight switch is a key location. a bad connection there could cause the problems. Are these connections serial or parallel? On rereading it, it seems that no current passes thru the ammeter as the load and power source are on the same post. Can you clarify? I've attached a high quality wiring diagram of how I did it. Quote Link to comment Share on other sites More sharing options...
Noah Posted July 16, 2020 Author Report Share Posted July 16, 2020 I do like the idea of the ignition switch possibly shorting. Quote Link to comment Share on other sites More sharing options...
Sniper Posted July 16, 2020 Report Share Posted July 16, 2020 From your drawing it appears the voltage to the ignition switch goes through the headlight switch? It should not if that is so. Please clarify Quote Link to comment Share on other sites More sharing options...
Noah Posted July 17, 2020 Author Report Share Posted July 17, 2020 22 hours ago, Sniper said: From your drawing it appears the voltage to the ignition switch goes through the headlight switch? It should not if that is so. Please clarify Not through it, good catch. Same post so the headlight switch feeds off the power going from the ammeter to the ignition switch. Quote Link to comment Share on other sites More sharing options...
plymjim Posted July 17, 2020 Report Share Posted July 17, 2020 One wire from starter solenoid to ammeter. Three wires from other post of ammeter to headlight switch, ignition switch, & bat. post of regulator. Per wiring diagram from Plym. manual. (Should be same as Dodge.) Diagram is posted somewhere on this forum. Sorry I'm not presently able to re-post it for you. And as Keithb7 said may be more than one issue. Regarding the sputter, check your condenser & coil. Good luck Quote Link to comment Share on other sites More sharing options...
The Oil Soup Posted July 17, 2020 Report Share Posted July 17, 2020 I don't see a ballist resistor in your diagram and it sounds like you are frying your coil. Quote Link to comment Share on other sites More sharing options...
Sniper Posted July 17, 2020 Report Share Posted July 17, 2020 If it's a 12v setup then yes it should have a ballast in run and I believe a D100 is a 12v system. Quote Link to comment Share on other sites More sharing options...
Noah Posted July 18, 2020 Author Report Share Posted July 18, 2020 (edited) On 7/17/2020 at 3:49 AM, Sniper said: If it's a 12v setup then yes it should have a ballast in run and I believe a D100 is a 12v system. Help! I do not have a ballast resistor, nor am familiar. I didn't see this in the diagram. Is there a size/specification that I need? The coil does get pretty hot. **Update: My manual says that coil resistor only applies to 8 cylinder. Does that change your thoughts? Edited July 18, 2020 by Noah Quote Link to comment Share on other sites More sharing options...
Sniper Posted July 18, 2020 Report Share Posted July 18, 2020 What is your system voltage? 6v or 12v? That is what will determine the need for a ballast resistor. Quote Link to comment Share on other sites More sharing options...
Noah Posted July 18, 2020 Author Report Share Posted July 18, 2020 12V Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted July 18, 2020 Report Share Posted July 18, 2020 ballast with 12 volt is needed if our coil is NOT internal resistor model....old style oil filled cannister coils are checked easily with an ohm meter...if you are between 1.2 and 1.9 with avg. at 1.4-1.7 you will want a dropping resistor (ballast) and rule of thumb is resistor matches coil impedance...now if you racing you will wish to do the math/test for amperage. For the street, not enough to worry about. If the coil is approx. 3.2 ohms +/_ .2 you are internally resisted and no external is needed....but beware these coils keep higher voltage on the coil longer and contribute to shorter life expectancy of the points. If you are up to a bit of search and read you may look also at e-core... Quote Link to comment Share on other sites More sharing options...
Sniper Posted July 18, 2020 Report Share Posted July 18, 2020 (edited) Mopar never used an internal resistor coil that I know of, but it doesn't hurt to check it. Odd that the OP doesn't have a ballast and not sure what manual he has. I expect to see a drawing like the following. Edited July 18, 2020 by Sniper Quote Link to comment Share on other sites More sharing options...
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