HEI Install Problems. Need Help.

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falconte43
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HEI Install Problems. Need Help.

Post by falconte43 »

I purchased the DUI HEI for my 1977 Jeep J10 360 V8 and have been trying for the last three days to get the truck to start. I am hoping you guys can help me point out what I am doing wrong. I wired the HEI using the relay method. Here is the diagram that I used.
HEIrelay01.gif
Using my voltmeter I checked that with the switch on the pigtail for the HEI is receiving 12.4 volts that should be good right?

Here is how I have been doing the install and lining up everything else:
-Set the engine to TDC, the line on the harmonic balancer lines up with TDC on the timing plate and I can feel pressure build up against my finger on the hole for spark plug #1.
-Drop the distributor in making sure that it seats fully against the engine, install the hold down bracket.
-Put the cap on and designate the nearest clockwise spark plug point (on the cap) number one, then continue with the firing order 18436572.

This has been my operating procedure.

Some questions that I am starting to wonder about. Does my designated number one on the cap have to be right on top of the rotor, or is it ok for it to be a bit clockwise from it?

I'm starting to go crazy over here.

Extra info...My timing plate only have TDC A5 and A10. Do I need to set the engine to something different than TDC?

Any help is welcomed. Thank you!
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1977 Jeep J10, 360 V8
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ghcoe
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Re: HEI Install Problems. Need Help.

Post by ghcoe »

Rotor has to point to #1 spark plug post. You could be off a tooth, but it should not matter as long as you can turn the distributor enough to bring it into time. As long as you got power you should be good.
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Stuka
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Re: HEI Install Problems. Need Help.

Post by Stuka »

For initial start, that #1 should be right at the rotor. If its off by a bit, rotating the distributer can fix that (ie: adjusting its timing). But if its quite a ways off, you may be a tooth off like ghcoe suggests.

Have you checked to see if its actually sparking? Take the number one plug wire, with a plug, ground threads, spin engine, should spark.
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falconte43
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Thanks ghcoe. I feel like this is what I have been doing. On this distributor there is not a designated #1 so I have been noting the placement of the rotor after install then making the next cap point clockwise #1. Does the #1 cap point need to be directly over the rotor?
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falconte43
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Alright, so make sure #1 point is directly on top of the rotor Stucka? I have been doing this by myself so I haven't been able to have someone start the truck for me. I might have an extra set of hands tomorrow.
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Stuka
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Re: HEI Install Problems. Need Help.

Post by Stuka »

Yeah, for first start, its easiest for it to point right over it. I have an HEI on my 258, although not a DUI. In case you have other questions, I can show my setup. Although not much to show.
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ghcoe
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Re: HEI Install Problems. Need Help.

Post by ghcoe »

Look up how to set up a remote start system. They are not to hard to make. Then you can work on this solo. Don't hang onto the spark plug for the mentioned spark test above! Sometimes you have to turn the distributor slowly while cranking the engine to find the sweet spot.
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falconte43
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Haha spark plug shock. Good suggestion on the remote start! I'm going on day four of trying to get this going. Lord help me.
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falconte43
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Stuka wrote:Yeah, for first start, its easiest for it to point right over it. I have an HEI on my 258, although not a DUI. In case you have other questions, I can show my setup. Although not much to show.
Stucka which method did you use to wire your hei?
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Stuka
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Re: HEI Install Problems. Need Help.

Post by Stuka »

falconte43 wrote:
Stuka wrote:Yeah, for first start, its easiest for it to point right over it. I have an HEI on my 258, although not a DUI. In case you have other questions, I can show my setup. Although not much to show.
Stucka which method did you use to wire your hei?
I took the 12V feed from the stock duraspark box (12 gauge wire that is already switched with ignition), and sent it over to the HEI. You however have a '77, which means you have a prestolite as I recall (78 was the first official year of the duraspark). So they are wired differently.

I do think you need to verify spark, especially if it has not even tried to run. I had mine started very first try, as there is not much to an HEI setup.
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Re: HEI Install Problems. Need Help.

Post by fulsizjeep »

On the 77, I used 16 GA Red with White tracer off the plug to the Prestolite ignition module (electronic control unit).

Image
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Updates my friends! So I grounded cylinder one spark plug and found that I had no spark. The relay I was using went bad early in the install. I wired straight from the positive side of the solenoid and now had spark. I went as far as pulling the rocker cover and finding TDC compression, installed the distributor, plug wires and still wouldn't fire. I could only try for so long before my battery drained. So now the truck sits at the mechanic shop near my work...

Sincerely,
Disappointed in Durham
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Stuka
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Re: HEI Install Problems. Need Help.

Post by Stuka »

Ahh bummer :(

Well, let us know what the mechanic finds.
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Re: HEI Install Problems. Need Help.

Post by fulsizjeep »

Boo-Hiss. Not a big fan of relays. Everyone should carry spares, LOL.
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Re: HEI Install Problems. Need Help.

Post by MJMadness »

fulsizjeep wrote:Boo-Hiss. Not a big fan of relays. Everyone should carry spares, LOL.
This.

A HEI will not draw anywhere near enough current to warrant the installation of a relay. It's a solution looking for a problem.
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Re: HEI Install Problems. Need Help.

Post by fulsizjeep »

Doh!

Sent from my XT1032 using Tapatalk
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motcat
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Re: HEI Install Problems. Need Help.

Post by motcat »

I have a DUI HEI in my 78 and did not use a relay. When I saw your first post with the diagram including the relay I was confused why this was in the circuit. My DUI instructions didn't suggest a relay, nor would I even thought of adding one.
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letank
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Re: HEI Install Problems. Need Help.

Post by letank »

motcat wrote:I have a DUI HEI in my 78 and did not use a relay. When I saw your first post with the diagram including the relay I was confused why this was in the circuit. My DUI instructions didn't suggest a relay, nor would I even thought of adding one.

No relay on the 74 as well, only a wire from the idle solenoid...
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Re: HEI Install Problems. Need Help.

Post by tgreese »

fulsizjeep wrote:On the 77, I used 16 GA Red with White tracer off the plug to the Prestolite ignition module (electronic control unit).
At the risk of piling on ... this. Use the power wire to the Prestolite module, or the red wire to the coil. They come from the same source, splice "L." No relay needed.
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falconte43
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Re: HEI Install Problems. Need Help.

Post by falconte43 »

Soooo, I fried the module. Summit is sending a free replacement as the distributor is still under warranty! Wooooo! And Tgreese, that is exactly how the mechanic wired it up. Great minds think alike.
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