• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Engine Rebuild

jones95xj

NAXJA Forum User
Ok, I'm having trouble figuring out if I should just do an Overhaul Kit rebuild or a Master Engine Kit rebuild.
My engine is making knocking sounds, and it has 230,000 miles on it.
Any advice would be appreciated.
Thanks
 
My buddy just got his 91 HO (w/190,ish on it) motor back recently from J+J in Ridgecrest, Ca. They checked and tolerances, machined with matching bearing sizes and supplied all new parts needed,and even reassembled head for $900 and change. He just had to assemble the rest. Not bad in IMO. Better than buying a rebuilt that was probably assembled in Mexico.
Check around your neck of the woods and see what the machine shops are offering. Good luck.
Joe
 
Another option to consider is a salvage/junkyard engine. Keep in mind that there are a LOT of 4.0 engines floating around and if you have the time to look for a good one, you should be able to find one with reasonable miles on it. You will have less $$$ invested with this option.
 
You shouldn't need to go with the "master" kit...just the overhaul should be fine...assuming the kits you are looking at are similiar to the ones that I'm familiar with. The master kits usually include new pistons. You're really looking for everything other than the pistons which most "overhaul" kits include. You want new rings, all new bearings, timing kit, new oil pump, new freeze plugs, and gasket kit. I may have missed something but you get the point. Also, you'll want to have the head rebuilt...unless you've done it before or have someone who can help you, just bring it to a good shop and let them do it. They will be able to do things you can't do such as "re-deck" it to make sure your surface is 100% flat. You'll also want to bring your block so they can check your cylinders and if you want, clean if for you to. They'll be able to get back in the water jackets where it will be difficult for you to go. Let me know if you have anymore questions. I've successfully rebuilt SEVERAL 4.0's. Good luck!
 
Where I'm looking the
Overhaul Kits include:
[FONT=Verdana,Arial] Pistons, Rings, Gaskets, Cam Bearings, Rod Bearings, Main Bearings, Thrust Washers, Aux Shaft Bearings (if applicable), and Valley Pan (if applicable). [/FONT]$270
[FONT=Verdana,Arial]
And
[/FONT]Master Engine Kits include:[FONT=Verdana,Arial] Pistons, Rings, Gaskets, Cam Bearings, Rod Bearings, Main Bearings, Oil Pump, Freeze Plugs, Camshaft, Lifters, Pre-lube, and Timing Set, and Valley Pan (if applicable). $[/FONT]450

BruceB83, where did you get your rebuild kits?
 
I always got them from the engine shop I used for machinery work. Your camshaft is probably fine but spend the extra $180 and just get new lifters and camshaft. Or, you could find an afermarket camshaft to get some extra torque. Check out the Xtreme 4x4 camshaft from COMP. I've personally never run it but one of the 4.0's I rebuilt had one go in it and my friend liked the way it performed so that's a thought too.

Another piece of advice...check your distributor teeth where it meets the camshaft and make sure you have no play in the dist. One of my dumba@@ friends destroyed his motor because he drove the piss out of it at high RPMS (note...the 4.0 is NOT a high RPM motor) and it basically wore it out and ate the teeth of the shaft of the distributor and the camshaft. He had to basically do a whole rebuild after that.
 
Back
Top