8BA starting/not starting question

CSArno

CSArno

Senior Member
I have a '49 F1 with an 8BA. Completely stock 6v system. A few times now it hasn't started first thing in the day. The first time it did this I put a test light from the battery to the coil input to make sure it was getting power. It was so I cranked it again and it fired right off. Its done this a few times since and every time I put a test light on it then it starts. New coil, new condensor, new points.
Any thoughts on what is causing this? Most of the time it does it when it's damp out..
I keep a test light in the truck now....

Thanks,
Chris
 
Bad battery/ground connections. With any bad connection moisture makes it a bigger issue. The clamps on the battery can develop a plating or film over them in a moisture environment. Do you have any grease on the battery terminals? If not, I would clean the terminals and coat them with a thin layer of grease and reconnect the terminals. The bad connection could be anywhere in the circuit, but I would start with the battery.
 
I'd check the ignition switch, and its connections.

Did your test light connect from battery ground (+) to coil (-) ? or battery (-) to coil (-)?
 
Make up a 6 ft test wire with alligator clips. Run the test wire from the switch to coil then resister to coil ,then battery to the switch ,coil to distributor ,any one of these should tell you were the low resistance is .Ted
 
I went both ways. Bat pos to coil neg and bat neg to coil pos. Both produced a light when it wouldn't start. Would turn over great, just wouldn't fire. I'll make up a jumper and do some more testing. Doesn't do it often, just annoying when it does.
 
Sorry, I think I mess read your original post! Just re-read it, seems the engine was cranking over just not starting, I first read it as not cranking. If it is a power to the coil issue, it has to be an ignition switch to resistor to coil issue. Could also be on the ground side of the coil or points. Same principal applies, most likely a lose or corroded connection (especially if it is worse when humid/damp).

Don't see how a jumper from the battery to the dist. side of the coil would tell you anything, but a jumper from the battery (-) to the (-) side of the coil (the side connected to the resistor/ignition switch) should eliminate problems on that part of the circuit.

If I am understanding what you were saying in #7 above, it sounds like you were crossing the polarization between the battery and the coil. The battery (-) should go to the coil (-) - the side that goes to the ignition switch. And the battery (+) side would go to the coil (+) - distributor side, however all that would accomplish is grounding the coil and bypassing the points. If you were going to do that to test the coil you would want to touch the jumper to a ground (any ground) and remove it to see if the coil would produce a spark. But do not leave it connected or you will burn up the coil.
 
Last edited:
You must log in or register to reply here.
Back
Top