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| | | | Joined: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | I currently have a 12v ……. 235 with points/coil etc (no upgrades). As I’m rewiring to fix the previous owners rats nest, I noticed that there is no ballast resistor on the fire wall. Doesn’t it require a ballast resistor so I don’t burn up the points? I’ve been driving it around town for about a year now. In the future, I plan to upgrade to HEI, I just don't have the funds to do it today.
Thoughts?
Chris | | | | | Joined: Oct 2021 Posts: 6,729 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,729 | Yes. You need one. 6v don't.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | Thanks Otto! I can’t believe I didn’t burn up my points already! I’ll do a temp install until I put my HEI on her. | | | | | Joined: Jan 2022 Posts: 2,441 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,441 | Maybe your coil is marked "12v" or "No resistor required"? Some aftermarket coils have a built in resistor. Like this one. Down side is that the coil doesn't produce a full spark while starting the engine.
'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: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | Morning Bill! I’ll take a look at it today when I’m playing with the wiring. | | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | If your multimeter has a "DC amps" function, you can measure primary current in the "engine not running/switch on/points closed" mode. Most points can handle a maximum of 5 amps without damage, but "less is better" as long as the engine starts and runs reliably.
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: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | Hotrod, I have a ballast resistor at the house, I think I’ll just throw it on until I get to the point of upgrading to HEI. | | | | | Joined: Jan 2022 Posts: 2,441 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,441 | Unhook both small wires from the coil. Measure ohms from one coil terminal to the other. Anything over 3.5 ohms (a guess by me, maybe 3.0 ohms) probably has a built in ballast resistor.
What part numbers and manufacturer name are on the coil?
By the way, does your starter have support to bypass the ballast resistor for easier starts?
'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: Jan 2014 Posts: 3,677 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,677 | Quasi-related question:
When a ballast resistor fails, how does it typically fail?
Is it just a total loss of continuity? Excessive resistance? Too little resistance?
1951 3100
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | The most common failure is an open circuit- - - -no current flow. A ballast resistor is just a coil of nickel/chrome wire, usually mounted in a ceramic heat isolator.
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: Jan 2013 Posts: 2,232 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,232 | Bill,
It’s a key start, not a stomp starter. | | | | | Joined: Jan 2022 Posts: 2,441 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,441 | So your starter solenoid will have 3 studs to attach wires.
A big stud for the battery cable.
A small stud (usually marked "S") that comes from the start position on the ignition switch. When activated, it causes the starter solenoid to pull in, engaging the starter drive gear to the flywheel and at the same time supplying power to cause the starter motor to spin.
Another small stud (usually marked "R") which passes battery voltage down the attached wire directly to the + terminal on the coil. This "bypasses" the external ballast resistor, supplying full battery voltage to coil + while starting the engine.
But before doing anything you need to find out if your coil has an internal resistor.
'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 2019 Posts: 4,472 AD Addict & Tinkerer | | AD Addict & Tinkerer Joined: Feb 2019 Posts: 4,472 | As Bill pointed out earlier, most coils are marked if they have a built in resistor. I would do a thorough examination.
Phil Moderator, The Engine Shop, Interiors and Project Journals1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc BrakesProject JournalsStovebolt Gallery Forum | | |
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