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87 2.9 to 91 4.0 wiring help


Brandoncw

Brandoncw

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OK, so my old 2.9 is quitting on me so I decided to swap a good 4.0 out of a 91 ranger. The tech articles weren't very descriptive on what wires go where so if anyone has experience with this swap please help
 


adsm08

adsm08

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Do you want it to look pretty, or just work?
 
Brandoncw

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Nothing about the truck is pretty by any means so it don't have to be pretty
 
adsm08

adsm08

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4WD
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OK, cool. That makes this pretty easy.

You can use the alternator sub-harness from the 2.9, you just have to move a few wires around and add a big on from the B+ post back to the starter relay.

Then you only have to splice like 2 or 3 wires to make it run. I can't remember the colors off the top of my head, I will look at them in a bit when I get a chance.
 
Brandoncw

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Awesome, I'm still working on pulling the 4.0 then I got to pull the 2.9 and put in the new motor. So I won't quite be to the wiring part until later this evening or tomorrow
 
Brandoncw

Brandoncw

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adsm08 said:
OK, cool. That makes this pretty easy.

You can use the alternator sub-harness from the 2.9, you just have to move a few wires around and add a big on from the B+ post back to the starter relay.

Then you only have to splice like 2 or 3 wires to make it run. I can't remember the colors off the top of my head, I will look at them in a bit when I get a chance.
Click to expand...
i really need the help now. decided to take my time on replacing gaskets and making the motor look nice. but now all that is out of the way, motor is in place, and im ready for the wiring part.
 
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