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| | | | Joined: Apr 2005 Posts: 2,832 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,832 | I have used internal resistor coils in the past to eliminate the ballast resistor but on latest project the points are overheating and turning blue. Voltage is 13.8 and one of Jon's condenser upgrades. Any suggestions? Thank you; Evan
Evan
| | | | | Joined: Mar 2014 Posts: 4,475 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,475 | Evan what color is that condenser? Red is one of the original ones (in which there were 2 or 3 recorded failures). Gray is the improved one. Please let me know via this forum or by PM.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | You should use a resister & matching coil. Coils with extra resistance are for tractors & other low rpm engines.
George
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Apr 2005 Posts: 2,832 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,832 |
Evan
| | | | | Joined: Mar 2014 Posts: 4,475 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,475 | Hmm. That's the good one. Nothing should make that one misbehave and all are tested twice before I use them. I'd be inclined to see if a ballast resistor will help and if so either get a new coil or hide the ballast resistor somewhere.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Jan 2022 Posts: 2,435 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,435 | Evan: If you are already using a coil with an internal resistor adding an external resistor wouldn't be a good idea.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | Wire an accurate ammeter inline with the coil temporarily- - - -the current draw should be less than 5 amps with the engine running. Either swap coils or add a resistor to keep the current draw down to a level the points can handle. At an applied voltage of 14, the resistance of the primary winding should be about 3 ohms.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Mar 2014 Posts: 4,475 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,475 | Evan: If you are already using a coil with an internal resistor adding an external resistor wouldn't be a good idea. I'm thinking there's a chance the internal resistor has failed and in the process of failure has now become a conductor...at least it sounds like that's a possibility.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Jan 2022 Posts: 2,435 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,435 | Most resistors fail open, not shorted.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | An "internal resistance" coil does not have a resister in it. It has more windings on the primary side which gives it more resistance. If it was that simple all manufactures would have used that kind of coil instead of having a ceramic resister or resistance wire in the harness.
George
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | Cold starting is much better if a low resistance primary winding is used for a hotter spark while the battery voltage is low because of the heavy current draw of the starter. Once the charging system kicks in, a resistor is needed to protect the points from overcurrent. The resistor is bypassed during cranking. The engineers who designed that system didn't just fall off the turnip truck on the way to the big city from the farm!
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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