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Old 08-13-2022, 09:11 PM   #1
mrbuck
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Need help electrical ?//

So today I planned on firing up my 56. This would be the first time I’ve ran the motor ( a turn key 350) dumped a splash of gas into the carb tube and bang she fired right up . So of course after a year of waiting I proceed to fire it off 6 or 8 times threw the corse of the day. Then the wifey rolls up and says let’s hear it. So I turn the key and nothin, not a click click not a grind of the starter nothin. I’ve got 12.5-13 volts at the starter, ignition switch, fuse panel( painless wiring kit and all new switches, ignition etc. )but as soon as I turn the key to accessory it drops to .5v?????any ideas? I’m totally lost why it would fire up 7,8 times then just quit.
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Old 08-13-2022, 11:37 PM   #2
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Re: Need help electrical ?//

send her in the house and try it, prolly work.
do you have power to the starter switch?
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Old 08-13-2022, 11:50 PM   #3
mrbuck
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Re: Need help electrical ?//

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Originally Posted by dsraven View Post
send her in the house and try it, prolly work.
do you have power to the starter switch?
There is power to the ignition and power to the starter. But once I turn the key even to acc. It kills the power
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Old 08-13-2022, 11:53 PM   #4
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Re: Need help electrical ?//

Check batt connections and grounds
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Old 08-14-2022, 12:16 AM   #5
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Re: Need help electrical ?//

Quote:
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Check batt connections and grounds
THIS!!!

Go back over every connection. Especially the ground connection at the engine. Make sure that you are making contact with clean, bare shiny metal.

Plus throw the charger on it for a few hours. It may be that all of those starts and short runs have just drained the battery a bit especially if you don't have the charging system hooked up.
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Old 08-14-2022, 09:48 AM   #6
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Re: Need help electrical ?//

If battery connection was bad, would I still have 1 volt at the fuse block and starter? Seems a bad connection would have intermittent power or low power every where.

One other thing I was thinking about is when it was started it would crank but not fire off until,the key was released from the start position, if hat makes any sense. ( it would crank for a second or two than as soon as I release pressure turning the key bam shed fire right off)
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Old 08-14-2022, 10:28 AM   #7
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Re: Need help electrical ?//

I have seen lots of cars where most electrical stuff works but then when you go to start it just clicks and goes dead. Battery terminals were dirty or loose. For your problem though, it kinda sounds like a switch problem. Have you checked the connections on the switch and also for what gets power when the switch is activated to start? Check power at the distributor when in start mode. Without going through your build thread I'm not sure what you have for a distributor, ign switch and if you have key start or push button start and how all that is wired in. For HEI the dizzy should be wired hot with key on or in start. With points there is a ballast resistor wired to feed the dizzy in run but for start it is bypassed and fed power from a connection on the starter solenoid.
If you go right to the starter with a jumper wire or remote start switch, does it crank like it should? Just click? Do nothing?
Testing for power with a meter or light can show battery voltage but when a bigger load is applied, like the starter, a bad connection will make the circuit fail.
Personally, I would start at the battery and work out from there. Voltage, load test if you can, terminal cleanliness-gotta be bright shiny metal on both parts, follow cables to ground and starter, same deal- voltage and cleanliness, shiny metal, ign switch and fuse panel- same deal. Then check switch outputs for proper power to each terminal at each switch position, try jumping power to the starter right at the switch to see if it bumps. Check power at the dizzy in each switch position as well.
Keep us posted. You'll probably find it was just something you forgot to tighten up or a wire came off
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Old 08-14-2022, 10:42 AM   #8
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Re: Need help electrical ?//

Thanks raven,
It’s got a new turn key ignition and hei dist. I guess I’m going to start checking everything

What a way to spend Sunday mornin!
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Old 08-14-2022, 10:49 AM   #9
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Re: Need help electrical ?//

Yeah, it sucks but grab a coffee and take your time. Sometimes it helps to have a check sheet and just check stuff off as good as you go through.if the ign switch is new you could do a quick test there first, new doesnt mean it is good. You could hot wire it at the switch and know right away.
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Old 08-14-2022, 10:59 AM   #10
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Re: Need help electrical ?//

Quote:
Originally Posted by dsraven View Post
Yeah, it sucks but grab a coffee and take your time. Sometimes it helps to have a check sheet and just check stuff off as good as you go through.if the ign switch is new you could do a quick test there first, new doesnt mean it is good. You could hot wire it at the switch and know right away.
Can I just jump,from the hot terminal to the starter terminal on the switch?
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Old 08-14-2022, 11:14 AM   #11
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Re: Need help electrical ?//

Yes if there is room use 2 jumper wires so the threads on the switch dont get arced and possibly jammed up. Otherwise try to use the nuts on the studs of the switch for your contact points. Try that, if it doesnt work go to the starter and jump from the big terminal to the small terminal that makes the starter operate.
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Old 08-14-2022, 03:17 PM   #12
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Re: Need help electrical ?//

Well I pulled the starter and bench rested it, it was shot. Lame since it came with the crate motor and only fired 8 times. Off to get a new one and see it that will fix the problems.
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Old 08-14-2022, 03:32 PM   #13
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Re: Need help electrical ?//

Wow, that is lame. If the starter motor works when jumped across the 2 large terminals on the solenoid, then it could be just a bad solenoid that would be cheaper than a starter. At
Any rate, when reconnecting, ensure the stud on the solenoid doesnt turn as you do up the bit, that sometimes can be the root cause.
Hopefully it's a cheap easy fix.
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Old 08-14-2022, 03:56 PM   #14
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Re: Need help electrical ?//

Well ****, got the new starter, bench rested it just to be sure, it’s good to go. Installed it hooked it back ok turned the key and nothin still.
I double checked battery to frame ground( clean and good connection)
Engine block to frame ground ( good clean connections)

But still at the ignition switch once I turn the key power drops from 13v to .5v

I get the same .5v at the distributor and the silenoid.
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Old 08-14-2022, 04:05 PM   #15
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Re: Need help electrical ?//

To me, it sounds just like a bad battery cable to battery connection. Have you removed them and cleaned the terminals and connections? A load test right at the battery would be a good idea, before you take anything apart. Test right at the cable, not the battery, so you know the system voltage. Turn the key on test voltage at the ign switch, the test it at the battery terminal. Then test it at the battery lug itself. If the system voltage says .5 right up to the battery, but the lug coming out of the battery says 12.6, then there is resistance in the terminal connection. Remove it and clean to bare metal.
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Old 08-14-2022, 04:07 PM   #16
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Re: Need help electrical ?//

If it turns out that the battery voltage is good and remains good with the key on, but you still only have .5v at the ign switch, then start at the battery and go to the next connection downstream of the battery. Keep testing till you find the voltage drop.
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Old 08-14-2022, 04:11 PM   #17
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Re: Need help electrical ?//

I have worked on cars where accy work, even headlights, but as soon as the starter is called for everything goes dead. Most of the time it is a bad connection at the Batt or in a batt cable. Since your stuff is all new it is unlikely you have a bad cable. The batt could be questionable if it has sat around for awhile not cycled. That's why I mentioned load testing or jumping the starter right at the starter, to see if the Batt and starter have the juice to work and it is a wiring or switch problem
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Old 08-14-2022, 04:12 PM   #18
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Re: Need help electrical ?//

Jumping the starter at the starter is like a load test for the Batt and also an operational test for the starter
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Old 08-14-2022, 06:07 PM   #19
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Re: Need help electrical ?//

NEVER ASSUME- TEST

I've been at this for over 50 years and normally it is because one assumes that something is good so they didn't thest it or check it that is where the issue is.

As Dsraven said, take your volt meter and start looking for a voltage drop in the system.

I keep saying grounds because I have gone out and looked at way too many cars with similar issues where the ground side was comprimised. Made a guy cry once because I took my knife out and scraped about five coats of paint away from under where his ground stap was bolted to the block but the car then cranked right over.

I've also see bad connetions in terminal ends. The worse being one that a guy just stuck the cable in the end of the terminal and crimped it but didn't strip the insulation.

i have a real issue with those skinny 4-0 cables you get at the parts house preferring to spend a few more bucks and get the 1-0 heavier cables. Usually they work when the engine is cold but when it and the starter get hot they don't carry enough amps.

I put 1-0 cables and converted my 454 powered flatbed to use a Ford Solenoid and that solved the cranking problems but this isn't a hot start issue that you are dealing with. It is a resistance in the system issue or a bad battery issue. meaning the battery could show proper voltage with a volt meter but has a bad cell or other internal issue. I would have it properly tested and eliminate that part of the equation.
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Old 08-14-2022, 08:21 PM   #20
mrbuck
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Re: Need help electrical ?//

I think I got it. It was a combination of things. Fist off bad battery connections, the terminal blocks where painted on the inside where they bolt onto the post, I never even thought to check there, figuring they know they need to be clear. Also had some some issues with the ignition switch, seems as one of the terminals was miss wired on the inside so it was getting power to the distributor. Lots of back and forth but I think she’s good to go now.
Thank you guys for the help.
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Old 08-14-2022, 09:03 PM   #21
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Re: Need help electrical ?//

thats great to hear, and it didn't spoil your whole day by not coming up with the fix. I kinda figured it would be at the battery since I have seen that many times over. the connection terminals look really good from the outside, without taking them off and checking the contact surfaces, so they get overlooked. good you found it and also learned a bit about troubleshooting.
post up a short video of it running if you get a chance. looks awesome so far.
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Old 08-14-2022, 11:54 PM   #22
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Re: Need help electrical ?//

That goes backk to the days when I was teaching automechanics and we would paint the inside of the battery cable clamp with clear nail polish so it wouldn't make contact when we were into trouble shooting.

I didn't even think of that because I am so used to taking my post cleaner and giving every cable I install a quick clean up new, old or ??
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77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.
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Old 08-15-2022, 08:28 AM   #23
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Re: Need help electrical ?//

Future testing can be made easier by using a "load light" to "stress test" the electrical system. For example, connect a really bright incandescent light (No LEDS!) across the battery cables then go hit crank. The light might go dim but it should not turn out. Often with bad battery connections the light will go out and stay out for a bit. Why is this a good test? The battery has to be able to provide enough power for the ignition system to work during cranking. If the battery and circuit can't light a test light then it won't start the truck. This same type of test is very effective at finding bad connections in other circuits but it requires a test device that can place a substantial load on the circuit being tested.
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Old 08-15-2022, 09:55 AM   #24
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Re: Need help electrical ?//

Now that is a great idea 1ptm. I have also used something like that to put a draw on a system to find a problem. Sometimes an old headlight or a heater motor, whatever I have handy at the time. I also have a small sealed beam trailer light with long pigtails and alligator clips on the wires so I can connect that to a circuit to test if it is getting power. I work alone mostly so no 'buddy" to help for a minute.
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