Hey folks - as you know from past posts of mine, I don't know squat about engines or electrical but I am having a problem with the starter and I know you all can help and thank you in advance. First let me describe what happened and that might be the clue. (1953 GMC converted to 12volt with original 228 stock and I drove it 1,300+ miles last summer from IL to FL with only minor problems.) Infrequently, when I would step on the floor starter, nothing. But if I waited 30 seconds and tried it again, it would crank and off i'd go. Recently, I was driving through the everglades and I thought I heard it cut out on the highway for a split second but was fine after that. Well about 10 minutes later I took my foot off the gas as I was headed for an exit and the engine cut out completely and that was all she wrote. As I coasted down the exit ramp, I put it in gear and popped the clutch, but it still would not start. Luckily that exit was the only gas (not service) station nearby and i was half way across Alligator Alley in the middle of the everglades so I had somewhere to sit and wait for the tow truck. I did notice a slight smoke coming from where the + battery cable attaches at the starter motor post under the hood. Sometimes it does take a while to actually start especially if I only shut it off for 30 minutes or so after running. And at the beginning of the above described leg of this trip, I had stopped for a quick bite before getting back on the road. I did have to "stand" on the starter button longer than usual to get the engine to finally turn over and run. Could I have burnt out the original 6volt starter? If so, should I have this one rebuilt to a 12v? I had to have the truck towed home. Since, I have cleaned up the battery terminals and inside collar of battery cables. Still NOTHING from the starter. I am assuming a simple electrical problem but not sure what. (this may be where I hear a collective DUH! across the world - but again, I know nothing). I found one small cap cover on the firewall with 2 fuses inside and they look fine. I have a mechanical friend coming by tomorrow and maybe he can understand better what you all are about to tell me. Thanks again and I can't wait to get back on the road.
To pin point the problem you'll need a test lamp and a friend. Take the battery cover from the cab floor. Touch the test lamp connections between the two posts on the battery. Don't touch the cables, touch directly to the battery posts. The lamp should light up brightly. If it doesn't, the battery is bad. Note the amount of light from the lamp. Have the friend stomp and hold the starter button. Touch one test lamp probe to the + battery post and the other probe to the battery cable end that connects to that same battery post (call this Point A). If the test lamp lights the fault is a bad connection between the battery post and Point A. Clean it and you're done. Touch the test lamp between Point A and the other end of that same battery cable where it connects to the stomp switch on top of the starter (Point B). Don't touch the switch, touch the cable. If the test lamp lights the fault is a bad cable between the battery and the starter switch. Replace it and you're done. Touch the test lamp between Point B and the stud on the stomp switch (Point C) that Point B attaches to. If the test lamp lights the fault is a bad connection between Point B and Point C. Clean it and you're done. Because you said the engine quit while it was running the next 2 steps probably isn't necessary, but you should try them anyway, just in case. Touch the test lamp between Point C and the other large stud (Point D) on the stomp switch. If the test lamp lights the fault is a bad stomp starter switch. Replace it and you're done. Touch the test lamp between Point D and the cable (Point E) that attaches to Point D. If the test lamp lights the fault is a bad connection between Point D and Point E. Clean it and you're done. Touch one test lamp probe to the - battery post and the other probe to the battery cable end that connects to the - battery post (call this Point F). If the test lamp lights the fault is a bad connection between the battery post and Point F. Clean it and you're done. Touch the test lamp between Point F and the other end of that same battery cable (Point G) where it connects to ????? It may connect to the frame or the engine. No matter, if the test lamp lights the fault is a bad cable between the battery and frame/engine. Replace it and you're done. Touch the test lamp between Point G and the bolt that holds the battery cable to the frame/engine (Point H). If the test lamp lights the fault is a bad connection between Point G and Point H. Clean it and you're done. If Point H is the frame (and not the engine) you'll need to do the same kind of testing on the ground cable that runs between the engine block and the frame. OK, you can tell your (ex) friend they can let go of the stomp now.
6 volt starters I had a similar problem with a 48 chevy car that the dpo had converted to 12 volt. Check the gauge of your battery cables. Modern cables will not carry enough amperage to the starter when hot. I changed my cables to the largest O or OO cables my local flaps could find. No more problem. Jim
Bill - thanks for the detailed steps - some portions completed Bill - thanks for the detailed steps - i did test the battery and all was good. I went ahead and replaced the both (+/-) battery cables with new 4 gauge just in case. I scratched the frame down to bare metal and used a new bolt/nut to reconnect the -neg cable to the frame. Still nothing. I have an elderly friend who is fairly knowledgeable about older vehicles but he is physically unable to come to the truck to help as he has some serious back issues right now. I asked if I removed the starter motor and brought it to him, could we bench test it and he said sure! So that is the new plan and i was able to easily remove the starter motor (with switch) today. Hopefully some time this week I can get it to him. I am still curious - could there be a wiring problem from the ignition switch that is the problem? Maybe a poor connection from the wires that go from the post on the starter switch and disappear into the firewall? Or would none of this be relevant? Thank you! - jd
Electrickery Fun ! I wish I were there as you have some very basic open circuit problem obviously . FWIW , 4 gauge cables are the bare minimum and the ground cable MUST NOT be attached the the frame ~ rather , it's vital it is bolted directly to the engine or transmission . This means you now need to measure up what you need then go order up a new 0 gauge ground cable . The starter issue may be as simple as removing the switch mounted on it then carefully polishing the copper contacts on the starter and inside the switch with METAL POLISH , never , EVER use sand paper or other abrasives on electrical contacts ! .
Wiring, eh? I'm assuming that everything else works? (Headlights, etc) It's weird to me that it wouldn't bump-start, but if there's one thing I've learned over the years, it's that weird coincidences happen all the time to throw me off the real solution. I definitely think you're on the right track with checking the starter. Running 12v through a 6v starter will eventually burn it out, but we get away with it because it's usually for such short timeframes. But if you've had to crank it longer, burnout could be your answer. Good luck!
