request your input on this YJ for parts

Bushmaster6

Legacy Registered User
City
the Springs
State
CO
#21
you guys confuse the cr-p out of me.. but I do appreciate your interest in getting me schooled

my very basic understanding of the OBD1 benefit is the so-called "5 wires to fire", which I interpret to mean there are five points that i must connect my existing engine harness to the new motor.. not sure how much of the old harness must remain vs what gets stripped out.. figure most of the engine control/ecu routing would have to remain.. I'm at a bit of a loss to get good info on this right now since CJOffroad is CJOffline..

Orionn, are you saying I could eliminate the entire Painless and route the YJ harness into the naked tub.. assume I'd have some modification to do at connections to guages, steering, etc? I also figure the back half of the body harness might come up short (wouldn't reach tailights, fuel sending units, etc)
 

bigwalton

Picture cravin' AK Postal nut
Staff member
SOA Member
City
Dexter
State
MI
#22
If you think this is confusing, CJOffroad will make your head swim and give you a migrane :D

Your understanding is correct, on the wiring side (assuming you otherwise mount/adapt/cool/fuel the motor) you can lay the entire YJ ENGINE harness and computer in your engine bay connected to the motor as it was and splice in your 5 CJ wires and it will start. From there you can start paring down the harness.

There's A LOT of paring down that you can do from that point.
 

Bushmaster6

Legacy Registered User
City
the Springs
State
CO
#23
just standing outside starting/looking at my YJ (now parked in my driveway), I sorta figured that.. seems most of the harness routes to the ECU/relay blocks, but only so much goes to the firewall.. assumption at this point is that it's a matter of figuring out what comes through the firewall that must be spliced, and eliminating the rest (lights, horn, directionals, etc)..

CJOffroad used to give me headaches, but I figured if I'd narrowed it down to a particular type/year/transition, it would help narrow the searches a bit.. in the end, I know there's some amount of "figger it out" I'll have to do, hopefully without damaging/burning/destroying too much
 

bigwalton

Picture cravin' AK Postal nut
Staff member
SOA Member
City
Dexter
State
MI
#24
Basically, if you just find the 5 wire functions you need to splice in, then use the FSM connector diagrams to locate those, that's what will have you in business the fastest. After that it's just connecting up the factory guages to get them to work (on the wiring side again obviously).

From my experience on CJoffroad, trying to search by year/model wasn't all that helpful because people didn't always list that out on some of the most informative posts. It's really a matter of looking for YJ OBDI swap info and using the FSM wire/connector diagrams, that's the kind of path that led me to completion. You may find someone who's got it specifically for your model/tranny/year, if so, great! Otherwise, I wouldn't look too hard beyond just the right wire functions and resort to the FSM to ID the wires.
 

Bushmaster6

Legacy Registered User
City
the Springs
State
CO
#25
thanks Eric..

figured that I'd have to do some discovery learning on the "five wires".. I suspect my experience with negotiating the Painless install a few years ago will help, and (since the truck hasn't been on the road) the painless harness has narly all of it's original labels still attached, that side will be easy.. the parsing of the YJ harness will be a little steeper on the learning curve..

it would be great to be able to at least see/talk to someone in person to get the "endstate" perspective but.. will figure it out.. much to do in the meantime: shopping CL for a engine hoist/stand to pull this thing this upcoming weekend :)
 

bigwalton

Picture cravin' AK Postal nut
Staff member
SOA Member
City
Dexter
State
MI
#26
Ask around on a local club forum for a hoist. I did just that for my swap and a guy who had one sitting in the corner of his garage collecting dust lent it to me for nothing. I ended up giving him $20 for beer when I returned it. :cheers:

Stands are pretty cheap, but get one that rotates if you're going to do much any work on it on the stand to clean it up or replace gaskets or whatever.
 

Orionn

Vehicular Packrat
City
Ann Arbor/Ypsilanti
State
Mi
#27
I haven't checked back here in a bit...Is there anything new going on?
Did you get a hoist/stand for the engine yet?

You mentioned a few post back about what I said about swaping the harness....Only the engine/underhood harness really needs to be swaped, then tie that into the painless harness from the firewall back.
Eric had mentioned this/cleared it up, my post is confussing . Sorry.

How did the engine compression numbers end up? have you had a chance to check them again?
 

Bushmaster6

Legacy Registered User
City
the Springs
State
CO
#28
Orionn,

I shifted my discussion of this YJ over to my Resto-mod thread in the "complete rebuilds" forum.. here

did a warm compresson test (wrong) and got quick compression build and another 120 across all 6 cyliners
did another test (on two cylinders) using more strokes and had consistent build to 150 before it leveled off
did not do the "wet" test at all..

had a question in the "engine" forum on the handpainted letters/numbers on the side of the block "D"s and "c"s hand painted below each spark plug... assumption is it has something to do with a rebuild/reman?
 
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