Another HEI Post (Sorry!): Install Assistance Needed

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Topic author
afterfrancesca
Posts: 9
Joined: Thu Dec 03, 2020 2:13 pm

Another HEI Post (Sorry!): Install Assistance Needed

Post by afterfrancesca »

New to the forums/newer to the FSJ world

Yeah bare with me I'm sure you all are sick of these posts haha.
I have done my searching and truly hadn't come up with results that fully answered my question. And so here I am, in advance, please forgive my lack of knowledge, I've had jku, XJs and an mj but this is a new beast for me;

I have a 1978 Wagoneer with the 360. The p/o lord help his soul, did some work under the hood, so to alleviate some headache and to figure out the no big start, I'm just going to install an hei. I get the fact I will take my old gear and install on my new hei distributor, but as far as where to get my 12v I'm a little lost. I have read that some use the fat red wire leading into the ICM on the fender, if I go that route will I just run my new 12 gauge wire from the distributor pigtail straight to where the red wire was and then rip all that out that was bypassed? I'm sure I'm completely over thinking all this, I just don't want to cut something out that I need.

Pictures would be greatly appreciated or any more details to help me out/input on what I should do.
Last edited by afterfrancesca on Mon Mar 08, 2021 3:07 pm, edited 1 time in total.
1978 Wagoneer
360 AMC• 4 bbl
J20 Axle Swap•
4.88 Gears
SOA•High Steer

75 Cherokee
Mellow Yellow Build
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Stuka
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Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by Stuka »

I think I have some photos, but they are on my home desktop.

But I used that thick red wire (mine had a white stripe on it also), which I verified with a multimeter that was switched 12V. It only got power when the engine was in start and run, NOT ACC. ALL the other wires I ripped out as they were of no use, as I had no intention of going back to the old ignition system.

If you really want to test run it, you could hook the 12V from the HEI to that wire without removing the old ignition module. Just remove the jacket from a 1/4" of the wire so you can tap into it.

Also, if the engine is not cranking over, the ignition system is not at fault. If its cranking, but not starting, then the ignition may be at fault. Failure to crank is typically caused by (discounting a dead battery) the ignition switch itself (at the bottom of the steering column), the starter solenoid on the passenger side fender, or the starter itself.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Topic author
afterfrancesca
Posts: 9
Joined: Thu Dec 03, 2020 2:13 pm

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by afterfrancesca »

Stuka wrote: Mon Mar 08, 2021 11:51 am I think I have some photos, but they are on my home desktop.

But I used that thick red wire (mine had a white stripe on it also), which I verified with a multimeter that was switched 12V. It only got power when the engine was in start and run, NOT ACC. ALL the other wires I ripped out as they were of no use, as I had no intention of going back to the old ignition system.

If you really want to test run it, you could hook the 12V from the HEI to that wire without removing the old ignition module. Just remove the jacket from a 1/4" of the wire so you can tap into it.

Also, if the engine is not cranking over, the ignition system is not at fault. If its cranking, but not starting, then the ignition may be at fault. Failure to crank is typically caused by (discounting a dead battery) the ignition switch itself (at the bottom of the steering column), the starter solenoid on the passenger side fender, or the starter itself.
Pictures would be amazing and I'd be beyond grateful (sorry for the hassle)

I know I have a lot to dig into/sort/figure out, sadly. The engine does crank like a vehicle would normally, fast I suppose you could say, just fails to get that last jump to turn over. I know the p/o said he would have to start it everyday then he went away for work for a few days and never started it again. Thought it to be a timing issue or some crappy wire install hack job. But I'll replace/look into the parts you mentioned, I'm sure it wouldn't hurt whatsoever.
1978 Wagoneer
360 AMC• 4 bbl
J20 Axle Swap•
4.88 Gears
SOA•High Steer

75 Cherokee
Mellow Yellow Build

letank
Posts: 4010
Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by letank »

welcome, otherwise crank, crank and no start, you might have a bad fuel pump/ filter / fuel line ... remove air filter, drop a little gas down the air horn , about 1/2 a shot... have a large rag -in case of fire to cover the top of the air horn, and choke the fire- crank and see if engine tries to start.

check the fuel filter position with the return hose on top - the 1/4 ID, the feeder is 5/16 and in the center/middle
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

Topic author
afterfrancesca
Posts: 9
Joined: Thu Dec 03, 2020 2:13 pm

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by afterfrancesca »

letank wrote: Tue Mar 09, 2021 5:50 pm welcome, otherwise crank, crank and no start, you might have a bad fuel pump/ filter / fuel line ... remove air filter, drop a little gas down the air horn , about 1/2 a shot... have a large rag -in case of fire to cover the top of the air horn, and choke the fire- crank and see if engine tries to start.

check the fuel filter position with the return hose on top - the 1/4 ID, the feeder is 5/16 and in the center/middle
Thanks for the welcome and input, I did add some fuel directly ,along with a bottle of fuel for pick up and not a single thing. I was installing new plugs and wires today and noticed the previous owner had the distributor cap and wires 180. I'm leading to believe that's a big reason haha. I really hate electrical I can do everything but. I'll be dropping the hei in tomorrow if the babies sleep, fingers crossed. New starter solenoid and switch arrives tomorrow just to cover all bases.
1978 Wagoneer
360 AMC• 4 bbl
J20 Axle Swap•
4.88 Gears
SOA•High Steer

75 Cherokee
Mellow Yellow Build

letank
Posts: 4010
Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by letank »

when I did the HEI, I used the wire to throttle solenoid as a feeder... you can use it to power the relay to the HEI
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

Eldog22
Posts: 47
Joined: Mon Dec 23, 2019 8:52 pm

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by Eldog22 »

Figure this out?

Topic author
afterfrancesca
Posts: 9
Joined: Thu Dec 03, 2020 2:13 pm

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by afterfrancesca »

Eldog22 wrote: Mon Mar 15, 2021 10:34 pm Figure this out?
Lol not really, upon removal of my dizzy I found the original gear was chewed up. So now I have to tear down everything in the front and replace what I can along the way because I'm not doing this again :P
1978 Wagoneer
360 AMC• 4 bbl
J20 Axle Swap•
4.88 Gears
SOA•High Steer

75 Cherokee
Mellow Yellow Build
User avatar

Stuka
Site Admin
Posts: 11789
Joined: Thu May 12, 2011 5:53 pm
Location: CA
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Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by Stuka »

afterfrancesca wrote: Tue Mar 16, 2021 5:33 am
Eldog22 wrote: Mon Mar 15, 2021 10:34 pm Figure this out?
Lol not really, upon removal of my dizzy I found the original gear was chewed up. So now I have to tear down everything in the front and replace what I can along the way because I'm not doing this again :P
How badly was it chewed up? There is always the concern of pieces of gear going through the oil system.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Topic author
afterfrancesca
Posts: 9
Joined: Thu Dec 03, 2020 2:13 pm

Re: Another HEI Post (Sorry!): Install Assistance Needed

Post by afterfrancesca »

Stuka wrote: Tue Mar 16, 2021 6:34 am
afterfrancesca wrote: Tue Mar 16, 2021 5:33 am
Eldog22 wrote: Mon Mar 15, 2021 10:34 pm Figure this out?
Lol not really, upon removal of my dizzy I found the original gear was chewed up. So now I have to tear down everything in the front and replace what I can along the way because I'm not doing this again :P
How badly was it chewed up? There is always the concern of pieces of gear going through the oil system.
The cam gear isn't too too bad but the dizzy was pretty rough. I'm still going to replace timing chain, drop the oil pan and clean that, may as well do water pump, oil pump install some msd gears etc. Then do a few oil changes. Definitely turned into a can of worms but I guess it needed the TLC regardless.
1978 Wagoneer
360 AMC• 4 bbl
J20 Axle Swap•
4.88 Gears
SOA•High Steer

75 Cherokee
Mellow Yellow Build
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