hit or miss starter/ 8BA

banjoQ

banjoQ

Senior Member
I have been chasing electrical gremlins for the last couple of weeks. Let me say, the information here on the Barn has been a great help. I have a 36' truck with an 8BA with two brush gen. What I am having trouble with currently is the starter. When cold, the motor turns over fine. After a few miles of driving, restarting can be a slow grind that picks up speed. This does not always happen but is happening more and more. The battery is holding a charge of approx. 6.6V. I have removed the starter solenoid and cleaned all contacts. Been going through and checking all grounds. I understand that grounds can be a source of many problems. Both the starter and solenoid are quite old but have been working for the last year or so. When things are cold, the starter sounds like it's in good shape, could my old solenoid be giving me these problems? Hoping someone can point me in the right direction. Thanks for any advice.
 
I would remove the starter and check the brushes and armature. 6.6 volts seems a little low for your battery. Also, take your solenoid apart by drilling out the rivets and checking out the inside contacts. You can reassemble it using small nuts and bolts or by drilling and tapping for small screws.
 
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I disagree. If your solenoid picks up, it's good and needs no maintenance. It's either good or bad, no in between.

Heat from all sources affects the conductivity of your wiring. This of course includes the heat generated by undersize cables. If you haven't checked this, next time this occurs and you grind away for a while, grab hold of the cable from the battery to the solenoid, see how hot it is. Also the cable from solenoid to generator. If hotter than the surrounding underhood sheet metal, you've identified the problem. 12 volt cable is smaller diameter than 6 volt cable, and will heat up considrably. You say you've been checking the grounds, ok, but also, the ground stgrap from the battery itself may be internally corroded from battery acid fumes, which can eventually shut you down completely. This also must be a heavy 6 volt strap.
 
Fordy- You stated that you thought that 6.6V was weak for the Batt. What should I expect from a six volt batt? I was having generator problems and have cycled the battery on a charger. The battery is much healthier than it was two weeks ago.
Alan- I will run the truck tomorrow and check as you described. The cables are very heavy gauge for a six volt system. I must admit that many of the components on my truck are very old (some wiring) and will be replaced as needed. The cables have probably been on the truck since the fifties. There is a good possibility that they are no longer doing their job. I have spare generators and starters but they are used parts and will be used for rebuilds.
 
After doing a little searching it seems that 6.6V indicates a fully charged 6V battery. I was incorrect.
 
Your battery cables including from solenoid to starter S/B as you indicate " very heavy gauge" in theory they s/b twice as heavy as a 12V set-up you see on modern vehicles. That's a good thing. However as others have indicated age and internal oxidation is your enemy. This and worn brushes / armature in starter will cause what's called heat soak which it sound as though what you are experiencing. It sounds like you have several gremlins in the works and will need to correct one at a time to ultimately resolve. Always start with the easiest fix ( usually the most economical as well ). If the cables / grounds are more than 15 or 20 years old, start there and stay with the heavy gauge. I think that will resolve 90% of your issues. If you still have similar issues you need to go internal on the starter, i.e. brushes and such. If you go into the starter do the full rebuild.
 
I agree with ford38 also check your starter doesn't take as much to crank a cold engine as it does a hot one if your starter bushing are worn it allows the armature to grind against the field retainers are the brushes good and like was said cables on these old 6 volts are a must to good for starting and charging hope this helps
 
Thanks for the info guys. Now we are getting somewhere. This truck sat for fifty years in a shed. It took a bit of work to get it to this point and it is not surprising that these components and cables are starting to fail. I have put at least 1,500 miles on it since getting it on the road. The batt. cables are cloth covered and appear gray inside. I will look into finding replacements today. They worked OK up until recently, so I let them be. I will also get a couple of my spare starters out and see if they have any life left. If not, a rebuild is in order. Any good books out there with this information? I will do a thread search and see if there is anyone who posted info and photos of their job. I have already priced out the cost of a having them rebuilt vs. buying new gens. and starters, almost a wash, will try and do the job myself. This is more of a preservation than a restoration. My goal is to just keep the old boy on the road and drive it when I can. For now, I just park on a hill. Just in case.
 
If you can find an old growler, you can check most of the armature stuff out yourself. I got one free from a friend that was gong to drag it off for scrap. Undercutting is sometimes needed on the commutator but not always. A Volt-Ohm meter will test the field coils. A heat gun can warm things up for testing if it is heat related but a growler will heat up the armature a bit too.
 
Just and update. Replaced both batt. cables and solenoid/starter cable. Old ones were grey inside, (oxidized) ? Thought I would replace the solenoid while I was at it. Cole Hersee unit that was shipped proved to be N/G out of the box. I cleaned up the contacts on my 65 year old one and re-installed. Seems the Cole Hersee units are now made in Mexico. Could just be a fluke. Anyway, there seems to be a vast improvement in the electrical system. Ammeter now reads correctly and starter cranks with authority. Thanks to all that shared their thoughts.
 
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