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engine swap $$$?

3KXJ

NAXJA Forum User
Location
minneapolis
I have a direct swap into a 90 XJ. Its a 4.0 HO out of wrecked TJ(9000 miles on it). I have all the needed parts. But I was wondering if anybody had a rough figure of the cost for the labor if I brought it in to a shop. I just don't have the time to try my first swap.
The only thing that I don't know is how to apapt the 4.0 senors to the HO. It has a stroker type injection with a crane cam and pace setters dual output header. The last thing I need is a throttle body. I can't decide if I want to go stock or RE. Any advise?
 
You could just take the TB and sencors from the Renix and put them on the newer block. You can take some #'s and mark your, connections on all the plugs in harness attached to motor. (one # on one side of connection, then matcht it on other side before unpluging) Go to a home repare shop (Home Depot) and hit the electrical isle and find a book of #'s. Start with 1 and go from there, mark all grounds with a 0. When you do the motor swap, pull each part off one by one, and reconnect to each connector as you put on new block. Or get the EMC (engine management control and harness) from the same block as the donar. Other than that, have no clue on how much it will cost. Pull two bults for motor mounts, pull trann bolts, and pluck the motor. Easy job.

Take it to a few diff shops you trust and get best estimate.

The swap can be done in a few hours, the most time will be the connections. What ever probs you encounter, the shop will too, if you want to save a few bucks, and get the help from the group, do it your self. Your choice.
 
thanx for the incoredgement. It sounds like good advise. I've heard of people takingup to a week to figure out the conections. I have no problem pulling the old one and dropping in the new, it's just that I don't have the time or another set of wheels to get to work. The thought was that if I could get it done for under a grand and it worked perfectly it would be worth the cost. Plus I could use the shops loaner while they were de-bugging the wiring. I wish I could do the swap but it's just a time thing. Thanx again.
 
Your '90 is the old Renix system. NONE of the engine sensors or controls will be the same. The simplest route would be to dump the custom header and use your exhaust manifold. Adapt the HO intake manifold to use your existing throttle body. (3 vs 4 bolt pattern, I believe).

The Renix uses three different temperature sensors. The one for the aux fan is in the radiator. Keep it. The one for the ECU is in the side of the block, low on the driver's side. The one for the gauge is in the head, left rear corner. The new HO uses one sender, in the thermostat housing, for all three functions. Assuming you will leave the aux fan alone, you need to account for two. The new engine I believe will not have a location in the head for the gauge sender, so you can use the thermostat housing for that one. Check the block to see if there is a plug you can remove for the ECU temp sender. It may be a solid boss that you'll need to drill and tap.

The new engine also won't have a knock sensor. You will need to mount your existing one (or a replacement) in the new block. The boss should be there, but it may need to be tapped. Caution -- this one should NOT be drilled through into the water jacket.
 
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