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matthones
July 3rd, 2014, 02:27 AM
Guys/gals,

Trying to troubleshoot a no spark situation. I don't know if it's the starter solenoid or the coil, but I know I get 12.8 volts right now from my battery to the starter and the engine turns over pretty good. I'm by myself so what is the best way to determine if there is voltage making it to the coil from the starter solenoid?

Can I leave the key in the run position and test at the coil, if so, what should the reading be, 12+ volts or will it be lower since the engine isn't turning?

Apologies for the dumb question, but trying to figure this out by myself and have run out of ideas.

Matt

RustyNut
July 3rd, 2014, 02:51 AM
Run a jumper from the postive side of the battery to the coil. (also known as "Hotwiring"). Turn the motor over. If it doesn't start... coil or distributor probs. If it does my guess is ignition switch powering starter but not coil.

Rusty

Culver Adams
July 3rd, 2014, 07:31 PM
Guys/gals,

Trying to troubleshoot a no spark situation. I don't know if it's the starter solenoid or the coil, but I know I get 12.8 volts right now from my battery to the starter and the engine turns over pretty good. I'm by myself so what is the best way to determine if there is voltage making it to the coil from the starter solenoid?

Can I leave the key in the run position and test at the coil, if so, what should the reading be, 12+ volts or will it be lower since the engine isn't turning?

Apologies for the dumb question, but trying to figure this out by myself and have run out of ideas.

Matt

Matt, the following post from RayCow about a year ago may help. (Thanks, RayCow for posting: I've pasted this into my "Glen's Auto Troubleshooting Guide" and refer to RayCow and Glen's now and again.)

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#2
June 23rd, 2013, 03:43 PM
raycow

Location: San Francisco, CA
Truck: 1960 C-10 Short Fleet

Default Re: Ignition help
Standard troubleshooting procedure:

Take off the distributor cap so you can see the points. Turn on the ignition switch and rotate the engine by hand until the points are open. Now use a
multimeter or test lamp to check for power at both the (+) and (-) terminals of the coil. If no power on either one, you have a break somewhere between
the coil and the switch. Work backward toward the switch, checking at each point where there is a terminal or connection until you find the break.

If you have power at (+) but not at (-), disconnect the lead going to the distributor. If you have power at (-) now, you have a short to ground somewhere in the distributor or the connecting wire. If you still have no power at (-) with the lead disconnected, you have an open coil primary, but this is VERY rare.

If power at both (+) and (-), turn the engine by hand until the points are closed. Now you want to see power at (+), but not at (-). If you still see power at both terminals, you have a break between the coil and the distributor, or else the points aren't making contact.

Ray

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Hope this helps and Have a great Fourth of July weekend,

Culver

matthones
July 3rd, 2014, 07:54 PM
Guys thanks for the quick replies. Turns my grandpa had installed a kill switch years ago that I took out of the truck to clean up the wiring mess under the hood. When I did that I inadvertently grounded out the coil. Once I pulled that grounding wire off it started right up. At least I got smarter along the way about checking distributor points and coils.