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Posted By Discussion Topic: Resistor getting hot     MGG 06-01-2019 @ 4:02 PM reply profile send p.m. Member Posts: 85 Joined: Jul 2014 Several of the major vendors also sell the 6volt positive ground Fun Projects regulator and may have them in stock if you do not want to wait. I have one on my 34 and it works exactly as advertised. Be sure to follow the installation instructions to the letter using an accurate amp guage. pajmward 06-01-2019 @ 2:37 PM reply profile send p.m. Member Posts: 11 Joined: May 2019 Thanks for your help. I will put a VR on as I have a sealed battery as well. I will adjust the 3rd brush to reduce the voltage in the meantime. TomO 06-01-2019 @ 8:02 AM reply profile send p.m. Senior Posts: 7385 Joined: Oct 2009 While you are waiting for a VR, it would be a good idea to reduce the charging rate by adjusting the 3rd brush in your generator. After thinking your problem with the hot resister over, you might want to remove your distributor and have the dwell checked. If your dwell is too long, both the coil and the resister will get hot enough to fail. Bypassing the resister increases the voltage to the coil allowing it to operate again. If you have a dwell meter, you can do a quick check by connecting the red lead to the screw that connects the condenser to the coil and the black lead to ground. Start the engine and read the dwell, it should be between 34-36 degrees and shoud remain withing those readings when the engine RPM is increased. Tom Dream38v8 05-31-2019 @ 3:13 PM reply profile send p.m. Member Posts: 211 Joined: May 2016 Tom, I was going to take your suggestion and purchase a Fun Projects voltage regulator as I have an Optima battery. When I went to the url provided it is for a 6v negative ground system, but I located the positive ground VR. They are on backorder. I will search the web. Thanks for the info relating to a sealed battery. Ray TomO 05-31-2019 @ 8:09 AM reply profile send p.m. Senior Posts: 7385 Joined: Oct 2009 To answer your question "Should the ammeter continiously stay charging at 10 - 12 amps when travelling for a long distance. I have a new battery which is fully charged when I start my drive." With the 3 brush generator, it will show the charging rate set by the 3rd brush adjustment regardless of the charge level of the battery. Your car does not have a voltage regulator, just a cutout relay that disconnects the generator from the battery when the generator voltage is too low to keep the cutout relay picked. The 3 brush generator charging rate is set by adjusting the 3rd brush. The charging rate is set just high enough to keep the battery fully charged. This rate depends upon your driving habits. To change the charging rate, remove the generator rear cover and move the brush to change the reading on the ammeter with the engine at 1300 RPM. This is a trial and error procedure. To decrease the amperage move the 3rd brush against the rotation of the generator. If most of your driving is short trips with occasional night driving, a good starting point for the adjustment is to turn on the headlights, pull out the throttle until the ammeter is at the maximum reading and then adjust the 3rd brush for a zero reading on the ammeter. If you are using a battery that has covers that can be removed to add distilled water to the battery, check the water level after every trip. If you have to add water more than once a month, the charging rate is too high. If you have a sealed battery, check the temperature of the battery by touch. If it feels hot, the generator is overcharging it. If it feels warm or cold the rate is probably OK. In any case if it were my car, I would install the Fun Projects voltage regulator. If you are using an Optima or any other sealed battery, IMHO the voltage regulator is mandatory. Overcharging the sealed batteries can cause them to overheat and explode. Tom 39 Ken 05-31-2019 @ 3:55 AM reply profile send p.m. Member Posts: 382 Joined: Oct 2009 You found the problem when you bypassed the resistor. Be careful of the "new" resistor. There have been reports of them being made with bamboo instead of ceramic and they will catch fire. Your old resistor can be repaired. Here is how it is done as described by my friend GM. "The original resistor is the one you want to use, they very seldom go bad. As long as you get continuity to both ends of the nichrome wire it can be fixed. Bend both covers up, scr*pe the end plates clean where the ends of the wire touches the end plate. Solder the wire ends to the end plate using ACID flux and lead solder. Other fluxes will not work. Clean with baking soda and water, blow dry and bend the covers back in place. I doubt with this fix the resistor will ever be a problem. G.M. " I hope this helps. pajmward 05-30-2019 @ 10:37 PM reply profile send p.m. Member Posts: 11 Joined: May 2019 The coil is an origional ford coil ontop of the distributor. I have changed the coil, went for a drive, still cut out. Changed the condensor, went for a drive same problem, which led me to the resistor. I am waiting for another resistor to see if that helps. Should the ammeter continiously stay charging at 10 - 12 amps when travelling for a long distance. I have a new battery which is fully charged when I start my drive. Thank you all for your help. TomO 05-30-2019 @ 7:21 AM reply profile send p.m. Senior Posts: 7385 Joined: Oct 2009 The 3 brush generator will continue to charge your battery, even when it is fully charged. This can shorten the life of the battery. The 3rd brush adjusts the rate of charge, and yours seems to be adjusted to the high side. You may want to buy a voltage regulator that fits inside your cutout. This has the advantage of keeping your battery fully charged without the risk of overcharging. Here is a source: http://www.funprojects.com/products/5055r.cfm Tell us about your coil. Is it the original type that mounts on top of the distributor or do you have an adapter plate on top of the distributor and a coil mounted somewhere else in the engine compartment? Tom 40 Coupe 05-30-2019 @ 3:57 AM reply profile send p.m. Senior Posts: 1801 Joined: Oct 2009 The resistor usually gets VERY hot. You may have found a problem with the resistor going open circuit when hot or it is possible there is another problem such as a bad condenser, coil or loose wire. By jumpering out the resistor your increasing (nearly double) the voltage to the entire ignition system and getting it to work. I would suggest you change the resistor with another (they measure 0.5 Ohm ) and take another trip. Before the next trip, charge your battery at home and then have it load tested at your local auto parts store to see if it is good. Did the ammeter just start measuring 10-12 A or has it been doing this??? The battery and the voltage to the ignition circuit are very much related! If your car has the Ford cut-out on top of the generator it does not stop the generator from charging. It disconnects the generator from the battery only when the engine is not running, so the battery does not discharge through the generator when the car is not running. The generator charging rate is set by the position of the third brush inside the generator. The position of the third brush doesn't change, so if the constant charge is a new problem I would disregard the cut-out and generator at this time. pajmward 05-30-2019 @ 2:23 AM reply profile send p.m. Member Posts: 11 Joined: May 2019 My 34 Ford resistor is getting hot after travelling around 30 miles. It will then break down and the power to the coil must be getting cut off which stops the engine. It is then not possible to start the engine untill the resistor cools down, however when I bypass the resistor the engine will start. Any ideas why the resistor is getting so hot, could it be the circuit breaker on the generator not shutting off when the battery is fully charged. The ammeter stayes at around 10 - 12 amps continiously while travelling even after 20 minutes running.

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