Mpgp1999 Posted February 24, 2020 Share Posted February 24, 2020 Hello on my 26 12v under heavy throttle the car backfires and afterfires. In the past I had an issue with a valve stuck open in the vacuum tank and raw fuel entering the motor bypassing the carburetor. But the car idles normally, so I do not believe this is the case. thanks Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 2, 2020 Author Share Posted March 2, 2020 Update I cleaned and gaped the points and plugs. That seemed to help. Now it is much harder for it to backfire. But when it does pulling the choke a little stops it. The problem was probably dirty contacts, slight timing problem, improper mixture. I noticed the cam in the distributor has rotational play. About 15 degrees. Is that normal? new issue not charging. With key on the amp gauge shows about 8 amps discharge. At the battery there is no charge it is at 12v. At the generator it shows 13.5v under throttle. Any ideas. I’m pointing my finger at the starter switch. The two negative leads, from generator and battery, show voltage and 0 ohms. When I engage the starter it shows no voltage. Shouldn’t it be the other way around? Link to comment Share on other sites More sharing options...
cahartley Posted March 3, 2020 Share Posted March 3, 2020 The backfiring is being caused by a too lean mixture. As I recall your car has the NorthEast starter/generator so I expect the foot starter switch is the same as was on my '24. Removing that switch is no piece of cake but, in addition to the starter terminals inside, there is an electrical cutout for the charging system. The points inside might need tuning up and, while it's handy, you might want to tune up the starter terminals as well. Link to comment Share on other sites More sharing options...
MikeC5 Posted March 3, 2020 Share Posted March 3, 2020 Pulling the choke out a bit to richen it may indicate a vacuum leak causing it to run too lean. Have you ever had the carb apart to verify the dashpot is able to move up and down? My distributor rotor has a similar amount of backlash that I suspect is normal. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 5, 2020 Author Share Posted March 5, 2020 On 3/2/2020 at 10:59 PM, cahartley said: The backfiring is being caused by a too lean mixture. As I recall your car has the NorthEast starter/generator so I expect the foot starter switch is the same as was on my '24. Removing that switch is no piece of cake but, in addition to the starter terminals inside, there is an electrical cutout for the charging system. The points inside might need tuning up and, while it's handy, you might want to tune up the starter terminals as well. How do I service/check the cut out Link to comment Share on other sites More sharing options...
MikeC5 Posted March 5, 2020 Share Posted March 5, 2020 You'll need to remove the starter foot switch box from the floorboard. This involves disconnecting the wires on the back side of it and removing the two bolts that hold it to the floorboard. Once removed, you can takes the screws out that hold the switch together, open the switch box to reveal the cut out relay. Do you have the Mechanics Book of Information for the car? Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 5, 2020 Author Share Posted March 5, 2020 I have the starter button out. There is a coil and several contacts. Between the battery and indicator there is 67 ohms. The points are chalky white. I have an original owners manual. For some reason I have voltage between the battery and starter terminal. When I disconnect them the terminals show no connection. The same for the leads. But when connected to the switch there is continuity. Link to comment Share on other sites More sharing options...
cahartley Posted March 5, 2020 Share Posted March 5, 2020 Points should never, ever, look chalky or even badly tarnished. You can check that the cutout coil is working using a battery charger. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 5, 2020 Author Share Posted March 5, 2020 I have an idiot automatic battery charger. It charges at 1.5a. How would I test it. Also the spring looks new. Link to comment Share on other sites More sharing options...
72caddy Posted March 6, 2020 Share Posted March 6, 2020 When I first purchased my 19 it would idle, but sputtered and backfired if I revved the engine. Then one day "bang!!!" Blew the seam in the muffler...very loud in a garage. So I was checking everything, pulled the distributor cap and just happened to notice that the cap had the cylinder numbers on top by each plug wire. Decided it couldn't be that simple. Sure enough, the PO had crossed two of the spark plug wires. Simple switch and all was good...until the next issue.... Link to comment Share on other sites More sharing options...
cahartley Posted March 6, 2020 Share Posted March 6, 2020 Matthew, I'm not sure if those battery maintainers put out enough juice but give it a shot. If that happens to not work use the car battery. The solenoid will use only the amount of current for which it is wound. You will figure out where both ends of the solenoid (electromagnet) are. Simply energize the coil (ignore polarity) and watch that the points close when energized. That you mention the spring on the solenoid looks like new bugs me and makes me think it's probably too strong. Over 93 years there may be a little wear here and there that may have to be compensated for. My preference is to have the points close with less juice rather than more. Link to comment Share on other sites More sharing options...
MikeC5 Posted March 7, 2020 Share Posted March 7, 2020 If you suspect the coil isn't working or not working properly, there is the option of dispensing with the coil/relay all together by using a diode instead. There are some threads on the forum that talk about it. I did it on my '25 and it was pretty easy and not very expensive. 2 Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 7, 2020 Author Share Posted March 7, 2020 The funny thing is there is a starter switch with a diode already installed. I was planning on swapping it out with an original coil one. Link to comment Share on other sites More sharing options...
MikeC5 Posted March 8, 2020 Share Posted March 8, 2020 I thought you said it had a coil and relay contacts. Did they leave the relay in place and install a small diode? It any case, if the contacts are really bad, it shouldn't be too hard to source another starter switch. Myers Early Dodge would probably have one http://www.myersearlydodge.com/catalog.htm Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 9, 2020 Author Share Posted March 9, 2020 I have two starter switches. One with a diode and another original. I get voltage at the starter generator while the motor is running. The amo gauge stays at 4 Amps discharge steady. There is no increase if voltage at the battery when there is throttle. I tried stepping on the stater while the motor was running and there was no change on the amp meter nor battery voltage. Currently the original coil starter switch is installed. the diode (on the bench) tests nothing one way and about 2 Ohms the other. Link to comment Share on other sites More sharing options...
MikeC5 Posted March 9, 2020 Share Posted March 9, 2020 My Starter/Generator had bad field windings and behaved similar to yours. When the SG is working properly, it should show maximum charge at idle and decrease as rpm goes up. Here is a wiring diagram that shows how it should be hooked up. I would assume for a '26, it would be the 8100-A switch. 2 Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 15, 2020 Author Share Posted March 15, 2020 UPDATE I Finally road tested and it failed horribly. Under a load the car will not operate. First gear I did not notice anything. One I got in the road it would not go faster than 10 mph. I had to nurse it to get there. The coil was very hot. The car idled fine. I changed the coil and there was no difference. The car kept backfiring. I changed the condenser to a spare I had. No spark. I put the old one back. Spark for 10 seconds. To add insult to injury it began to pour. Currently The car will not charge. The car will not stop and the car will not start. The motor will turn over. I have exhausted every resource and all my knowledge I have come to a dead end. Hopefully you guys can guide me. Link to comment Share on other sites More sharing options...
MikeC5 Posted March 15, 2020 Share Posted March 15, 2020 (edited) I would go back to basics and double check things like the static timing, points adjustment and wiring connections. Even if the generator won't charge, the car should be able to run on a fully charged battery for quite a while (without headlights on). If everything seems to be in order, I would then start taking a closer look at the carb. Also, what do the plugs look like? Edited March 15, 2020 by MikeC5 (see edit history) Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 18, 2020 Author Share Posted March 18, 2020 (edited) The plugs are new champion w18 recommended by the latest DBC newsletter. The points look pitted. The condenser failed the light bulb test. I ordered a “new” condenser from romar. My carburetor was rebuilt by Vern barker I am confident that it is at least close to proper adjustment. Edited March 18, 2020 by Mpgp1999 (see edit history) 1 Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 21, 2020 Author Share Posted March 21, 2020 Some good news in these times. I went to my local auto parts store and picked up a cheap condenser. I saw there was sparking between the coil wire and exhaust manifold. I moved the coil on to the fender and she fired up. 2 Link to comment Share on other sites More sharing options...
MikeC5 Posted March 22, 2020 Share Posted March 22, 2020 That's great! I have a coil like that sitting in the open hole where the original coil lived. It has been working fine. I wish the repro coils weren't so expensive. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 25, 2020 Author Share Posted March 25, 2020 The spark plug wires are arching to the block. If they appear to be fine and running normally and I put my hand near them I will get shocked. They are recent wiring. New wires with cloth cover to look old. In the photo above you can see a part of a rubber hose. The spark goes through the hose to ground. I can see this happening. Link to comment Share on other sites More sharing options...
Bloo Posted March 25, 2020 Share Posted March 25, 2020 (edited) One possibility is a defective part causing the firing voltage to be really high. Check your plug wires with an ohmmeter. Should be very low resistance if they are recent repro 7mm cloth wires (they don't make them in resistor versions). Look at your rotor and see if any pieces have fallen off. Look under your boots where the wires meet the cap for severe corrosion. Lastly, and maybe most importantly, look at the carbon button inside the distributor cap, and make sure it is contacting the rotor. Edited March 25, 2020 by Bloo (see edit history) Link to comment Share on other sites More sharing options...
Mpgp1999 Posted March 26, 2020 Author Share Posted March 26, 2020 The wires all have less than 1 ohm. I put dielectric grease on the connections in the boot. The connections are only a year old. I did not see any corrosion. 1 Link to comment Share on other sites More sharing options...
Bloo Posted March 26, 2020 Share Posted March 26, 2020 Well, if there's nothing wrong with the rotor or the carbon button in the distributor cap, I suppose the wires are just shot. I just brought it up because usually when wires fail that way (arcing out the side), there is some other root cause, like either the insulation was burned from heat, damaged from oil, or the voltage was unexpectedly high. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted April 12, 2020 Author Share Posted April 12, 2020 There was resistance from the distributor cap to the wires. I cleaned the contacts and put some dielectric grease where the wires connected. That reduced the ohms. Now the resistance is fairly low. I ended up pulling the fuse on the starter to test drive it. It has a new condenser. I can see that sometimes there is some arching behind the starter button. I think that it is making contact with the block. Currently the car will not charge nor stop. I’ve given up on the brakes. The pedal goes to the floor and the car doesn’t slow down. If I tighten it to where the pedal travel is good I can not get the wheels to move. I went around the block and I did not touch the brakes and they are smoking. I then let them cool and I was on a slight hill using the service and hand brake I could not prevent the car from rolling. Link to comment Share on other sites More sharing options...
MikeC5 Posted April 12, 2020 Share Posted April 12, 2020 As for the brakes, it may be that the external contracting band (that has the brake lining material) is insufficiently round and so it can be adjusted close to the drum without excessive rub. If the internal (parking brake) brakes don't work, look closely for signs of an oil leak from the end of the axle. If the internal brake shoes are contaminated with gear oil, they won't be very effective. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted April 12, 2020 Author Share Posted April 12, 2020 The brakes are dry. A few years ago they got soaked is oil. I replaced the felts. The transmission slowly pumps oil into the differential. I have replaced the gasket and bearings but it still leaks. I just drain it a few times a year. I full the transmission to compensate. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted April 13, 2020 Author Share Posted April 13, 2020 I disconnected the generator while running and I can see that it is clearly producing voltage. The lead has 0 ohms to the frame. There is voltage between the battery and starter terminal on the starter button. For the time being I am ruling the starter generator out a faulty. I am looking into the wiring. The switch tests good in the bench. The starter and battery terminals test ♾ ohms. When connected to the leads there is 12v. I am getting somewhere slowly. 1 Link to comment Share on other sites More sharing options...
Mpgp1999 Posted April 13, 2020 Author Share Posted April 13, 2020 I disconnected all the wires from the amp meter and traced them. Turns out it was wired incorrectly. It is now charging. 1 Link to comment Share on other sites More sharing options...
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