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01-19-2015, 11:25 PM | #1 |
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"need help" 68 gmc
Okay guys I need help with my 68 GMC. When I turn the key to start the truck it runs but when I let go of the key to the run position it dies. What can this be??? It ran fine before then started doing this now and then and now it will not run less I keep the key in the start position. Thank you in advance
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01-20-2015, 12:06 AM | #2 |
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Re: "need help" 68 gmc
Points or hei distributor?
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01-20-2015, 12:22 AM | #3 |
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Re: "need help" 68 gmc
Its hei
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01-20-2015, 12:25 AM | #4 |
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Re: "need help" 68 gmc
Gotta be the ignition switch then!
You got a dedicated 12 v to that hei? |
01-20-2015, 12:57 AM | #5 | |
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Re: "need help" 68 gmc
Quote:
Trace the HEI power and let us know how it's wired.
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01-20-2015, 12:52 AM | #6 |
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Re: "need help" 68 gmc
I will check tomorrow
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01-20-2015, 01:05 AM | #7 |
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Re: "need help" 68 gmc
I will do that that. Thanks guys I will let you know tomorrow its really cold where I'm at right now.
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01-20-2015, 01:19 AM | #8 |
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Re: "need help" 68 gmc
Farmington huh???? Howdy from Kirtland... I too am willing to bet on the ignition switch
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01-20-2015, 09:39 AM | #9 |
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Re: "need help" 68 gmc
Reason it runs when it's in start position is there is a jumper wire from the starter to the coil to provide a "hot start" of 12v on a points setup. When switched to hei it wasn't eliminated. Check the power along the key on hot to figure out the problem.
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01-20-2015, 10:06 AM | #10 |
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Re: "need help" 68 gmc
If a dedicated hot 12V source was added for the HEI this would not make a difference. Sounds like it worked fine for a while. My bet is the ignition switch as well.
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01-20-2015, 10:09 AM | #11 |
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Re: "need help" 68 gmc
Well if the dedicated 12v key on hot somehow became broken or disconnected it would. It's worth checking the wire for power at both ends of nothing is coming out of the ign switch then it's bad. If that was the case it's likely other components would not be working suddenly as well.
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01-20-2015, 11:29 AM | #12 | |
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Re: "need help" 68 gmc
Quote:
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70 C/10 SWB 402/TH400/3.73 "The Needy Beast" 200,000 Mile Club Disc Brake Club Owner installed options: Front Sway Bar Power Steering Power Brakes Cigar Lighter Courtesy Lights Deluxe Side Markers Wiper Delay Power windows Power Locks Sniper EFI 2015 Silverado 1500 LS 4.3/6L80/3.23 lowered 2" front & rear |
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01-20-2015, 10:19 AM | #13 |
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Re: "need help" 68 gmc
Thank you guys for all the info. After work today I will be checking what you guys asked me to.
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01-20-2015, 12:23 PM | #14 |
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Re: "need help" 68 gmc
farmington huh, heck yeah its cold there, I hunted 2b last year, big buck but i froze!!!
let us know what you find
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01-20-2015, 09:20 PM | #15 |
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Re: "need help" 68 gmc
Okay so I changed the ignition switch and also the tumbeler. Its doing the same thing as before. The power wire for the distributer is coming off the small post on the starter.
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01-20-2015, 09:34 PM | #16 |
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Re: "need help" 68 gmc
Okay then you need a key on hot to the hei. Get out the test light and find one under the dash. It should light up with the key on and shut off with the key off. Once you have located one find a place to tie into it and then run that wire to the positive side of the coil. There might also be an open terminal on the fuse block that's key on hot. That's my preferred method.
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01-20-2015, 09:33 PM | #17 |
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Re: "need help" 68 gmc
What color is it? For the HEI you need to run at least a 12 gauge wire and it should be dedicated. Most guys run their power directly from one of the IGN unfused terminals at the fuse box.
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01-23-2015, 10:26 PM | #18 |
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Re: "need help" 68 gmc
Okay guys with a test light key off in the back of the ignition switch there is power ing post and no power on the pos pos. Key to the run position there is power to both ing and pos. So with that said it should run but it don't.
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01-23-2015, 10:49 PM | #19 |
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Re: "need help" 68 gmc
Okay so now the wire going from the distributor to the small post on the starter. I put a jumper wire straight from the battery to that same wire and it runs just fine. Why would it run one day just like it is and not now? The wire is just fine, but ran derect to the battery its it runs good. I dont get it.
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01-23-2015, 10:53 PM | #20 |
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Re: "need help" 68 gmc
Sounds like you need to run a new ign wire then. Eliminate the one to the starter as that's only necessary for points ignition. Run it from the positive side of the coil to a terminal on the fuse block that's key on hot. That will take care of the issue.
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01-23-2015, 11:16 PM | #21 |
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Re: "need help" 68 gmc
Just did it and runs good now. Thank you everyone!
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