2.5L Engine Swap: Any Last Minute Advise?

[Comanchemodder]

Truck:  '87 Comanche, 2WD, 2.5L, AX-4.

 

This labor day weekend I will be swapping a '94 YJ 2.5L into my truck.  Since this is may daily driver, I want to make the swap over the weekend and hope to foresee any major issues.  Let me know if you have any things I should be prepared for.  So far:

 

1) I stripped the '94 engine down to long block; Pulled the pan and inspected the engine; looks good.

2) Will use the existing RENIX harness, ECU, intake and exhaust

3) Will use the '94 distributor, but the RENIX coil

4) Will swap over the RENIX fly-wheel to the '94 during the swap (Thanks Cruiser).

5) Will use the '94 alternator

6) Will use the '94 power-steering pump

7) Planning on pulling the complete trans and engine at the same time; unless not worth it?

8) Will use the '87 starter; seems to be newer than the '94 starter.

 

Any other major items?

[JeepcoMJ]

It won't run with the 94 flywheel...unless you mean swap the renix onto the new motor.

 

You will have to do a bit different wiring to use any 94 electrical compoments.

 

You will need the cam sensor from renix distributor, if thats even possible

[Comanchemodder]

 

 

You will need the cam sensor from renix distributor, if thats even possible

 

I will use the RENIX distributor then.  Thanks.

[JeepcoMJ]

Pulling engine and trans.does make it easier, bit fromt clip must be removed to do so....that is easy tho

[jimoshel]

Planning on the very same swap, only a '94 XJ instead of  a YJ. Waiting to see how it turns out. Thought about swapping everything over, engine, wiring harness, ECU, dash, everything but couldn't see any benefit for the extra work so not going to.

[Comanchemodder]

Hi Guys.

 

I am pulling the flywheel of the renix engine and will place onto the YJ.  Is there an "orientation" relative to TDC?  It seems the flywheel is symmetric, but there is a "gap" in the CPS teeth.  Just want to make sure it is oriented properly.

 

[JeepcoMJ]

Bolt alignment will only allow inatall in one location. Loc-tite all bolts on flywheel to crank upon install

[Comanchemodder]

I moved both engines to TDC for both the flywheel and distributor transfer. 

 

Loc-tite even with the factory torque spec (50 ft.lb+60 deg)?  Thanks in advance.

[mvusse]

Yes, loc-tite even with the factory torque specs. And locating to TDC is not necessary because, as Pat pointed out, the bolt holes are not symmetric. There is only one way they will all line up.

[carnuck]

When you take the flywheel off there is a locater hole on the crank from what I remember. It leaves a "shadow" which I used to line mine up. The head even interchanged when I went from a '95 YJ to an '84 Cherokee (carbed). All I did was swap the manifold. I think the coolant sensor may have been an issue (no hole on the new motor on the head) but the one on the thermostat housing worked.

[Comanchemodder]

I got a straggler.. What is the bottom (large) barb fitting for?  its on the engine side of the throttle body.  I can't seem to find the mating end.

 

[88whitemanche]

Top is for map sensor against firewall and bottom hooks up to a vacuum hose on the valve cover

[Comanchemodder]

Mission accomplished.

 

Lessons learned:

 

1. The YJ accessory pulleys are not offset as much. I had to use all the YJ accessories including the power steering and alternator. I had to rig up an external regulator from a dodge pickup since the YJ is externally regulated in the ECU.