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Am I set up as Positive or Negative Ground?

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Jim_Gruber

Jim_Gruber

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Terminal on coil labeled SW goes to 12VDC Power

Terminal labeled CW goes to the terminal on the Dizzy.

I think Bugsy IV is then set up as Negative Ground?

Can someone verify for me please.

Trying for a possible start tonight.
 
SW for "Switch" and CB for "Contact Breaker". You are set up for what the car was originally designed for....positive ground!:wink-new:

Kurt.
 
Thanks Kurt, after some more conjuring I figured it out. Now to get those strange nuts for the coil tightened back down. another PITA Design.
 
What cable goes to the starter...if it is the positive, you have negative ground.......if it is the negative that goes to the starter, you have positive ground (as the motor was originally designed).
Cheers,
Scott in CA
 
Car is set up as Positive ground. OK so I added a ground strap wire over the weekend that runs from the upper 5/8" bolt that connects the starter to the engine down and around to the threaded 5/8" hole on the bottom of the chassis. This is a 19" piece of battery cable with lugs on both ends. I cleaned up the bolt that the lug goes through with my die and used a Dremel with a wire wheel to clean things up where the lug gets tightened by the bolt. No ground strap previously existed. Validated that the coil was set up as Positive ground, Positive cable attaches to the firewall. Engine previously turned over vigorously. I connected up the battery charged and charger shows battery to be 100% charged. Pull the Starter Knob and I hear Click. Nothing. Any idea team. I did change the filter but all was disconnected at the battery when I was doing that. I didn't mess with the connection at the Starter but it could be an issue. Ideas come to mind. I disconnected the Ground Strap just in case and I get the same result. I also rotated the knob on the Bendix and it is free to turn. Puzzle time.
 
I will add I have Dash Lights so I am getting power.
 
From what you've said, it can really only be 1 of 3 things.
1. bad connection between the battery and starter (maybe the "solenoid")
2. bad starter
3. engine locked up

It's strange that the engine turned over earlier. Were the spark plugs then?
 
New Solenoid, Plugs were in, Starter worked previously. Need to noodle on this one. Connection at starter is greasy I'll pull tomorrow and clean up and see if that resolves and I will remember two wrenches to loosen that bolt. And Battery is disconnected until I puzzle this one out.
 
You have high resistance somewhere from a poor connection. It's either, as mentioned already, a battery cable, starter or pull starter. The battery is the most likely culprit., so clean the post and inside of cable clamp, and also if the battery clamp, clamps to the cable itself. Those wire strands can corrode without you realizing there's a bad connection in there too.

One more thing, DO NOT unscrew the nut on the starter post without also holding the inner nut. Doing so can and will lead the the connection to the armature breaking or at least become marginal.
 
To test for a high resistance connection I use the 'spit' test first since a high resistance connection can get pretty hot. Next I feel the connections for a hot spot. That is, of course, after having put a good load on the circuit. I'd be with others...check the battery connections first.

Kurt.
 
One of the battery connectors is an original helmet type. Betting that's the source of the problem. Will replace and save that one for resale. And Gerard that's what I said two wrenches to disconnect that solenoid to starter cable. Thanks guys I'm just puzzled why it turned over so easily before. I'll get it resolved.

Car Show is Saturday. Plans have changed for Bugsy driving there to being a candidate for Diamond in the a Rough and arriving by trailer. But he'll be there.
 
An additional quick test to determine the source of the resistance is to bridge the threaded post terminals on the solenoid using insulated handle pliers or a suitable screwdriver (don't forget to put the transmission in neutral first). If the engine spins over normally with the threaded solenoid terminals bridged you have a resistance problem with the solenoid contacts. If it turns slowly or not at all, it may be cable resistance or a problem with the starter motor itself.
 
That's the plan guys to figure it out tonight. I'm going to replace the Battery to Solenoid and Solenoid to Starter Cables. They are original to this car. $30 at O'Reilly I'm all for originality but need reliability first and foremost. And those Helmet type cables are available if I really think they look that good.
 
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