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2.5L Rebuild advise......


Member Number 257
NAXJA Member
Ok, I have got to do something about the engine so I figured I'd go ahead and bite the bullit and rebuild. I know my compression is low so I figured on a master rebuild kit. I was thinking of pulling the head and go ahead and getting it done till I can get the time to pull the engine and tear into it. Wold this be ok to do even if the head sits while the engine block work is getting done? Or should I wait and try to do it all at once? Also, when I order the rebuild kit can I go ahead and do that or do I need to tear into the engine and get some specks first. I have never done this but have local jeepers that have that will help. Any advise and experienced recomendations would be greatly appreciated.
I know this might not be the answer you're looking for, but have you considered getting either a different engine (bigger... not sure what options you have with your earlier model) or just getting another xj and put the two together??? a 4.0 is way more fun then the 2.5.... which seems to be giving up the ghost... :D

Well, actually I'm going to be getting an MJ doner carcas/engine to rebuild and swap to FI. I have the 5.0 that GaMike hooked me up with but am not ready for that yet. (Busted a D35 shaft I think with the current engine) So need to wait on that swap especially after Fore Wheeler and One Ton broke their D60 and 9"! And what better way to learn about engines than to rebuild one and be involved in the process. I also want to bore it to go with the stage 3 cam I have and the junk yards around here want a mint for an engine and no guarantees! As for bigger engines, yea I have considered the 3.1 and 3.4 swap but right now I think I want to rebuild and improve what I have. I feel like I need the experience b4 taking on a dig dog swap! Maybe it's the wrong thing to do but hey its fun.
I had a 85XJ 2.5L that I upgraded to an 86XJ throttle body injection setup. It is a bit of work. You have to swap the bell housing as well as the whole wiring harness under the hood and either splice it at the firewall or to replace the harness under the dash. It makes a nice difference in performand and starting.

I live at high altitude and am a mechanic so I built a 4.7L stroker. The hassle of swapping that into an early XJ is that you have to tear the front radiator support and related parts from a later model and swap them over. You even have to swap the hood. The complete wiring harness has to be swapped as well. Your existing transmission won't match up any more. All in all it is a big job. I love my stroker with 300hp and 325ft/lbs of torque, but It would have been cheaper to find a newer rig with a 4.0L to start with, but I always have to do it the hard way.

Tom Houston
Loveland, Colorado
Yea that is why I wanted that wire harness of yours. LOL!
Sorry, I didn't look at who did the post. LOL

Tom Houston