ballast resistor
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2nd Gear
Joined: Jul 2013
Posts: 2
Likes: 0
ballast resistor
My 61 cut off on me while driving and smoke came out of the hood. I opened the hood and saw the ballast and wirers going from there to the starter and coil were cooked. I replaced the wires and ballast and the car started fine, but than the ballast has gone bad twice since. Has anyone got any ideas what my be causing this problem.
Melting Slicks
Joined: May 2007
Posts: 3,461
Likes: 18
From: cooper city florida
Bob what do you mean "go bad". The only way a ballast resistor can go bad is to go open, or lose continuity. If you put an ohm meter across the terminals and you see a short, the resistor is good. Do you have shielding over you distributor? Are you using points? Your original problem was probably a grounding of the bk/pk wire......maybe at your shielding. Is your coil compatible with an ignition ckt that uses a ballast resistor? Most aftermarket coils have "use with ballast resistor" printed on them.......by the way, it is normal for a ballast resistor to get very hot to the touch under normal operation.
Le Mans Master
Joined: Oct 2000
Posts: 8,897
Likes: 1,357
From: Santa Ana CA
I'm thinking that the resistance of the coil is too low (could be the wrong coil or the winding could have gotten hot enough to melt the varnish on the wire and cause a partial short within the right coil) and this is pulling too much current through the system causing too much heat in the resistor and wiring.
Try a different coil that is known to work properly with the resistor.
Try a different coil that is known to work properly with the resistor.
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
I'm thinking that the resistance of the coil is too low (could be the wrong coil or the winding could have gotten hot enough to melt the varnish on the wire and cause a partial short within the right coil) and this is pulling too much current through the system causing too much heat in the resistor and wiring.
Try a different coil that is known to work properly with the resistor.
Try a different coil that is known to work properly with the resistor.
Drifting
Joined: Oct 2001
Posts: 1,770
Likes: 33
From: Cohasset MN
2017 Corvette of the Year Finalist
2016 C1 of Year Finalist
Make sure the resistance of the replacement ballast resistor is the same as the original. I tried to replace the one on my '57 as it showed some cracks in the porcelain (or whatever it is), and the car would hardly run.
And yes, they do get very hot.
And yes, they do get very hot.
Drifting
Joined: Dec 2010
Posts: 1,778
Likes: 1,552
From: Las Vegas NV
Bob what do you mean "go bad". The only way a ballast resistor can go bad is to go open, or lose continuity. If you put an ohm meter across the terminals and you see a short, the resistor is good. Do you have shielding over you distributor? Are you using points? Your original problem was probably a grounding of the bk/pk wire......maybe at your shielding. Is your coil compatible with an ignition ckt that uses a ballast resistor? Most aftermarket coils have "use with ballast resistor" printed on them.......by the way, it is normal for a ballast resistor to get very hot to the touch under normal operation.
