DCR Posted December 24, 2010 Share Posted December 24, 2010 I've been lurking on the sidelines for a couple of months trying to learn about the B Model Mack. I am now learning how much I don't know! My truck arrived yesterday, a 1958 B61T converted to a dump. When I looked at it and kicked the tires and test drove it, the truck had a problem with batteries and not starting. Jump the batteries and it would start. The first thing I did when I got it home was check the belts. They were so loose that the fan would spin freely. I replaced the belts, jumped the batteries and it started. This morning it would not start again. Jumped the batteries and it started right up. I charged the batteries. Took it for a drive to the license bureau to have the VIN number checked (non Ohio title so VIN has to be verified) and get it registered and new title work. I thought that the drive would charge the batteries. Wrong. On way back home, light changed, quick stop and stalled the engine. Yes, I am not a truck driver. Truck would not start. Jumped batteries and it started. I checked the generator and it is not showing any output. At this point do I replace/rebuild the generator or install an alternator? The existing batteries are 2 12 volt batteries. I understand the the factory setup was 4 6 volt batteries. Do I replace with two 12's or go back to the 6 volt batteries? I am calling on the brain trust for guidance as to what to do. I am sure that as I get into more items that I will have many more questions.I am still leaning my way around this site so if this post in not in the proper thread I apologize. Quote Denny330-550-6020A "Mack Pack" Charter Member Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/ Share on other sites More sharing options...
leversole Posted December 24, 2010 Share Posted December 24, 2010 I've been lurking on the sidelines for a couple of months trying to learn about the B Model Mack. I am now learning how much I don't know! My truck arrived yesterday, a 1958 B61T converted to a dump. When I looked at it and kicked the tires and test drove it, the truck had a problem with batteries and not starting. Jump the batteries and it would start. The first thing I did when I got it home was check the belts. They were so loose that the fan would spin freely. I replaced the belts, jumped the batteries and it started. This morning it would not start again. Jumped the batteries and it started right up. I charged the batteries. Took it for a drive to the license bureau to have the VIN number checked (non Ohio title so VIN has to be verified) and get it registered and new title work. I thought that the drive would charge the batteries. Wrong. On way back home, light changed, quick stop and stalled the engine. Yes, I am not a truck driver. Truck would not start. Jumped batteries and it started. I checked the generator and it is not showing any output. At this point do I replace/rebuild the generator or install an alternator? The existing batteries are 2 12 volt batteries. I understand the the factory setup was 4 6 volt batteries. Do I replace with two 12's or go back to the 6 volt batteries? I am calling on the brain trust for guidance as to what to do. I am sure that as I get into more items that I will have many more questions.I am still leaning my way around this site so if this post in not in the proper thread I apologize.I just (two weeks ago) went through the SAME thing you are...I went to NAPA and purchased a Delco 10SI 63 amp alternator and modified the generator bracket and viola...no more charging problems...also added a dash light so the alternator would "switch on", as it needs a resistance in line with a switched 12 volt input...I am still dealing with two old undersized POS dead cell worn out batteries, but I am going to remedy that tomorrow! Two group 31 twelve volts with 1000CCA each...My advice is to spend every night reading these forums, it is the only way to learn, just about anything you could want to know is here, and has probably been answered. Quote Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69119 Share on other sites More sharing options...
Rob Posted December 24, 2010 Share Posted December 24, 2010 I've been lurking on the sidelines for a couple of months trying to learn about the B Model Mack. I am now learning how much I don't know! My truck arrived yesterday, a 1958 B61T converted to a dump. When I looked at it and kicked the tires and test drove it, the truck had a problem with batteries and not starting. Jump the batteries and it would start. The first thing I did when I got it home was check the belts. They were so loose that the fan would spin freely. I replaced the belts, jumped the batteries and it started. This morning it would not start again. Jumped the batteries and it started right up. I charged the batteries. Took it for a drive to the license bureau to have the VIN number checked (non Ohio title so VIN has to be verified) and get it registered and new title work. I thought that the drive would charge the batteries. Wrong. On way back home, light changed, quick stop and stalled the engine. Yes, I am not a truck driver. Truck would not start. Jumped batteries and it started. I checked the generator and it is not showing any output. At this point do I replace/rebuild the generator or install an alternator? The existing batteries are 2 12 volt batteries. I understand the the factory setup was 4 6 volt batteries. Do I replace with two 12's or go back to the 6 volt batteries? I am calling on the brain trust for guidance as to what to do. I am sure that as I get into more items that I will have many more questions.I am still leaning my way around this site so if this post in not in the proper thread I apologize.If the batteries have went near completely flat (discharged), you will probably need to repolarize the fields in the generator to set up the initial magnetic field to start it again. With the engine running about 1000rpm touch the "F" terminal on either the voltage regulator, or terminal on the generator itself with a wire from the positive battery terminal for just a second. It may just start to charging.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69123 Share on other sites More sharing options...
DCR Posted December 27, 2010 Author Share Posted December 27, 2010 (edited) Rob and Leslie,Thanks for the response on my not charging post. With Christmas, cold and snow, I have not had a chance to look at it yet. I've been reading many other posts on converting to an alternator and eliminate the old technology of a generator so will do that as soon as I can. I bought the truck to use and drive and not for show so I don't have to keep everything original. Many years ago my Dad had a Model A Ford and I remember converting the brakes from rod type mechanical to hydraulic. Wasn't original but sure stopped better!I think I am also converting to a negative ground system and 12 volt starting in the future.Denny Edited December 27, 2010 by DCR Quote Denny330-550-6020A "Mack Pack" Charter Member Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69300 Share on other sites More sharing options...
gearbox Posted December 28, 2010 Share Posted December 28, 2010 I would try to charge the 2 12 volt batteries and like Rob said repolarise the generator and see what happens. 6 volt batteries in my experience are not as reliable as 12 volt and alot easy to purchase cheers Gearbox Quote Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69304 Share on other sites More sharing options...
DCR Posted December 30, 2010 Author Share Posted December 30, 2010 Weather finally is cooperating and had a chance to re-polarize generator. Nothing happened and still not charging. I will now replace generator with alternator. Can anyone tell me what to do with the generator wires and the regulator wires? Thanks.Denny Quote Denny330-550-6020A "Mack Pack" Charter Member Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69448 Share on other sites More sharing options...
Rob Posted December 30, 2010 Share Posted December 30, 2010 Weather finally is cooperating and had a chance to re-polarize generator. Nothing happened and still not charging. I will now replace generator with alternator. Can anyone tell me what to do with the generator wires and the regulator wires? Thanks.DennyBefore you make the final determination to replace you might have someone sit in the driver's seat while the engine runs at a fast idle. Flash the fields again on the generator and have the person in the seat tell you if the ammeter deflects when you touch the "F" terminal with the battery positive jumper lead like before. If the generator is defective, the needle will not deflect. If the needle moves toward the positive side, you have a defective regulator, or interconnecting wiring between the two units.Replacing the generator with a modern day alternator is not a bad idea, however there really is nothing wrong with a properly operating generator also.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69449 Share on other sites More sharing options...
other dog Posted December 30, 2010 Share Posted December 30, 2010 Before you make the final determination to replace you might have someone sit in the driver's seat while the engine runs at a fast idle. Flash the fields again on the generator and have the person in the seat tell you if the ammeter deflects when you touch the "F" terminal with the battery positive jumper lead like before. If the generator is defective, the needle will not deflect. If the needle moves toward the positive side, you have a defective regulator, or interconnecting wiring between the two units.Replacing the generator with a modern day alternator is not a bad idea, however there really is nothing wrong with a properly operating generator also.RobA generator is easy to rebuild too, though I haven't done it for years. Can you even get new brushes for them anymore? Quote Producer of poorly photo-chopped pictures since 1999. Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69450 Share on other sites More sharing options...
Rob Posted December 30, 2010 Share Posted December 30, 2010 A generator is easy to rebuild too, though I haven't done it for years. Can you even get new brushes for them anymore?Very easily obtained as are the brush block holders, spring, bushings, roller bearings, etc.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/16992-truck-arrived-and-i-am-full-of-questions/#findComment-69452 Share on other sites More sharing options...
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