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AH restarting after 7 years no driving - coil

peteatgr

Senior Member
Offline
/ubbthreads/images/graemlins/confused.gif I'm trying to get my AH BJ8 restarted after a long layoff in the garage and I am having trouble getting a spark. I've installed a new battery and checked all of my wiring up to the ignition switch and then onward to the coil. I've installed a new coil (Napa). The car turns over fine but I can't seem to get a spark from the coil. I can measure 12V from the negative post side of the coil and I've got good continuity from the positive post on the coil all the way back to the ground wire on the trunk battery switch. I'm trying to test the coil by removing the coil wire from the distributor cap and holding it near the engine block while the car is turned over. I'm looking for an intermittent blue spark. I can't seem to get it. Am I missing something simple or is this just an improper way to test the operation of a coil? Does anyone know a good book that details the proper efforts and checks for getting a car back on the road that has been put away (and in all likelihood was put away with any prep for storage) for about 7 years?
 
Sounds like the points are not opening & closing properly.

A/ With the ditributor cap off, put a small 12v bulb across the points and turn the engine over slowly (with the ignition on) As the points open the bulb should light dimly (it's is series with the coil) and when they close the bulb should go out.

B/ Turn the engine until the points are closed. Turn the ingition on and open them with with a bit of plastic - as they open you should get a spark 1/4" long AT LEAST from the coil HT to ground. If not suspect the capacitor ('condenser' in old parlance) or the way the bushes are assembled on the points spring pillar which should be in such a way that the sping is isolated from ground.

Good luck.
 
Hi peteatgr,
Welcome to the forum. A simple possibility could be the battery switch in the trunk. The little blk/wht wire attached to it is an anti-theft device that grounds out the coil. Try disconnecting that wire at the switch and tape up the exposed wire so it won’t ground out and try starting again.
 
Thanks to everyone. This is all really good stuff for a guy who is just getting back into all this.

Andrew - I am going to check the points (I have a new set I haven't installed yet and a new condensor also. They'll probably go in quite quickly now.)

Greg W - So that I understand the concept of the operation of the ground wire on the battery switch in the trunk - I should have continuity through that wire when the battery switch is "off" so that it disables the coil? And I should loose continuity through that wire when the battery switch is "on" so that it does not act as a ground for the coil when the motor is running?

zblu - Not sure I understand what you mean by the "capacitor wire on the coil". What rubber bushing? My coil has positive and negative wire posts and the socket in eh center for the insulated wire going to the distributor cap. The only capacitor/condensor that I know of is inside the distributor. Is that what you mean?

Thanks to all,

Pete
 
Check the wire form the side of the distributer to the coil for good contact and the wire on the inside the distributer from there.(brown color and very flimsey). Also try another rotor to see if you have a problem with that bugger.
 
[ QUOTE ]

Greg W - So that I understand the concept of the operation of the ground wire on the battery switch in the trunk - I should have continuity through that wire when the battery switch is "off" so that it disables the coil? And I should loose continuity through that wire when the battery switch is "on" so that it does not act as a ground for the coil when the motor is running?

[/ QUOTE ]
Yep, if you look at the wiring diagram, the wire goes from the battery switch up to CB on the coil, then to the breaker. If the battery switch doesn’t open, you’ve got a straight shot to ground from the dizzy.
 
[ QUOTE ]
So that I understand the concept of the operation of the ground wire on the battery switch in the trunk - I should have continuity through that wire when the battery switch is "off" so that it disables the coil? And I should loose continuity through that wire when the battery switch is "on" so that it does not act as a ground for the coil when the motor is running?
Pete

[/ QUOTE ]

Pete--

Why not just cut the b/w wire at the coil and tape it off and eliminate the possibility of the switch being your problem.

After you get the car started replace the shutoff switch with a proper one--the originals are accidents waiting to happen. A search of the archives will give you info on good parts sources.
 
Thanks Michael. I think I will do just that. Beautiful 100M!

Pete
 
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