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  Topic Review (Newest First)
12-28-2017 12:13 AM
justals
Quote:
Originally Posted by jeepzjgrrl View Post

Do you have part numbers? I sent them an email and got no reply
Hesco part number p5007148
12-27-2017 08:12 PM
87MJTim PM sent
12-27-2017 08:00 PM
jeepzjgrrl
Quote:
Originally Posted by 87MJTim View Post

He did my wiring harness for my 84. I sent him the complete engine bay harness from a 93 XJ. He cut out the wires I did not need and labeled the wires for what to connect to.

I laid out the CJ harness and the modified XJ harness on the garage floor and marked/identified the five wires to connect on the CJ. I have fired up the engine .

His fee was about $250 if I recall. I paid the USPS to mail it to him. He paid to mail it back.
Omg THANK YOU! I will send him a message
12-27-2017 04:50 PM
87MJTim
Quote:
Originally Posted by tchimmerroks View Post
The member on this Forum who would thin out a Cherokee harness to mate to your 4.2L wiring for the 4.0L conversion is thisguyyouknowI didn't use his service, but his price/expertise sounded pretty reasonable. Good luck
He did my wiring harness for my 84. I sent him the complete engine bay harness from a 93 XJ. He cut out the wires I did not need and labeled the wires for what to connect to.

I laid out the CJ harness and the modified XJ harness on the garage floor and marked/identified the five wires to connect on the CJ. I have fired up the engine .

His fee was about $250 if I recall. I paid the USPS to mail it to him. He paid to mail it back.
12-26-2017 08:03 PM
tchimmerroks The member on this Forum who would thin out a Cherokee harness to mate to your 4.2L wiring for the 4.0L conversion is thisguyyouknowI didn't use his service, but his price/expertise sounded pretty reasonable. Good luck
12-26-2017 02:29 PM
Matt1981CJ7 Probably this one:

http://www.hesco.us/products/7902/40...8#.WkK-9COZOL8

Matt
12-26-2017 12:44 PM
jeepzjgrrl
Quote:
Originally Posted by justals View Post
I have the 258 block with 4.0 head on my 85 cj. Purchased the engine harness from hesco.
Do you have part numbers? I sent them an email and got no reply
12-26-2017 12:42 PM
jeepzjgrrl
Quote:
Originally Posted by CrankyD View Post
Do a search for 4.0 five wires to fire. That will get you started on how the two systems merge. The Painless (10150?) harness I have actually had very little in the way of engine management wiring. It did not include any of the ignition system wiring. All of the wiring from the bulkhead connector to the ignition module and over to the distributor is re-used from your old setup. I will be swapping in an MPFI based injection system soon and plan on using a harness scavenged from the junkyard. The painless harness will run the starting circuit and all the gauges though.
Thanks for your help. Wiring radios and lights I can do but wiring an engine or even merging 2 harnesses together is Greek to me. So all the help I can get is great
12-07-2017 10:12 AM
CrankyD Do a search for 4.0 five wires to fire. That will get you started on how the two systems merge. The Painless (10150?) harness I have actually had very little in the way of engine management wiring. It did not include any of the ignition system wiring. All of the wiring from the bulkhead connector to the ignition module and over to the distributor is re-used from your old setup. I will be swapping in an MPFI based injection system soon and plan on using a harness scavenged from the junkyard. The painless harness will run the starting circuit and all the gauges though.
12-02-2017 09:47 PM
justals I have the 258 block with 4.0 head on my 85 cj. Purchased the engine harness from hesco.
12-02-2017 09:07 PM
Rtracy2001
Quote:
Originally Posted by jeepzjgrrl View Post
so here is an update...and i am shocked that this isnt a question more people have...Painless wiring does not have a harness for this setup. remember its a 258(4.2l) bottom end with a 4.0l top end with fuel injection. and a 1996 Cherokee was the host for the harness and the top end. I need to just rewire the entire 86 CJ7 over again. i found where the grounded out pos wire is from the starter to the battery but i do not know how to properly rewire a starter from battery to starter and to ignition....does anyone know of someone in New Jersey that can help.
You will probably not find a wiring harness specifically for the 4.0L top and the 86 CJ-7 bottom. So far as I know, that unicorn doesn't exist. Also, that isn't what you need. You need a stand alone harness for the 4.0L and you need to clean up part of the original 86 harness. Don't get too hung up on having a 4.0L head on a 258 bottom end; it really doesn't matter as the differences between a full 4.0L swap and the 4.0L head only are minimal. Most any product intended to swap in a 4.oL will have everything you need (except maybe the alternator wiring). If you have the $$, a stand alone harness for the 96 engine is your best bet. Give Hesco a call and ask for a stand alone harness for a 1996 4.0L. They will also have instructions on how to splice that into your 86 so it doesn't look like it was attacked by the rat equivalent to Martha Stewart.

As for the rest, you will need to get a wiring diagram for the 86 and identify the circuits you must keep. The starter, oil pressure, and temperature are a few of the big ones. You won't need hardly any of the actual engine harness.

If you don't have the money for a stand alone harness, you will have to take the diagrams already attached to this thread and trace each wire, removing the ones not needed. Tedious PITA for sure.
11-28-2017 11:35 AM
jeepzjgrrl
Quote:
Originally Posted by jeepzjgrrl View Post

I sent them an email. Let's see if they can make a harness.
Update: They never emailed me back.
11-08-2017 11:05 AM
jeepzjgrrl
Quote:
Originally Posted by firegod33 View Post

Sounds like you're talking about this.

http://www.hotwireauto.com/?page=sales-jeep
I sent them an email. Let's see if they can make a harness.
10-10-2017 12:47 PM
firegod33
Quote:
Originally Posted by jeepzjgrrl View Post
Thank you, i sent them an email looking for a wiring harness for a 258 bottem end and 4.0 top. lets see what they come up with....i dont mind paying 500 bucks if it works they way it should. also i remember seeing a guy on one of these sites that says he can outfit a 4.0 wiring harness for the conversion and you ship him they Cherokee wiring harness and he will outfit it for the 258 and then send it back. havent been able to find it since.
Sounds like you're talking about this.

http://www.hotwireauto.com/?page=sales-jeep
10-09-2017 06:45 PM
jeepzjgrrl
Quote:
Originally Posted by schardein View Post
http://www.hesco.us/products/7902/40...6#.WdLxnEyZOT8

Hesco makes the kits for MOPAR. Here is a link to what you need, but it is not cheap. They also sell the individual parts. I bought parts from them about 20 years ago when I swapped in an entire 4.0 into my CJ.

From reading your posts, I think you are on the right track to find someone knowledgeable to help. Pointing them towards the Hesco website may help when it comes to finding parts.
Thank you, i sent them an email looking for a wiring harness for a 258 bottem end and 4.0 top. lets see what they come up with....i dont mind paying 500 bucks if it works they way it should. also i remember seeing a guy on one of these sites that says he can outfit a 4.0 wiring harness for the conversion and you ship him they Cherokee wiring harness and he will outfit it for the 258 and then send it back. havent been able to find it since.
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