I was wandering once I hit 300k they say u have to rebild ur motor. Was wandering what it means to rebuild it. Like what parts do I need?

 

It only needs to be rebuilt if something is wrong. If you have little to no blow-by, oil pressure is good and you don't hear any knocking or other bad noises just run it.

 

i agree with him

 

But say something does go wrong and I do I just want to know what I have to do

 

well it all depends on what happens or what goes wrong. cant really say what you gotta do till something happens that needs done

 

At the very minimum it would require new rings, bearings, seals, new timing chain set, honing the cylinders, checking clearences, cleaning all of the oil passages and installing new freeze plugs. Then once you install the engine you'll want to replace all of the cooling system hoses and replace the plugs, cap, rotor and wires. For a few hundred more dollars you could go crazy and install a performance cam. For another few hundred more you could have the cylinders bored and install over sized pistons. For about 500 bucks on top of all that you could build a stroker and have more low end grunt and good top end power.

 

First of all, there is nothing magical about 300k for needing a rebuild. Drive it until you have symptoms or issues.

And if/when that happens, you should also consider trying to locate a salvage yard engine and swap it in.

Doing so is really a very economical way to re-power an older XJ and it doesn't break the bank. A rebuild or purchasing a reman engine and having it installed is not inexpensive.

I've swapped in countless engines during my 38 years of wrenching and only been burned once.

 

Here are some things to check to see if your engine needs rebuilding.

-Significant oil consumption (check for leaks, etc also)

-Low oil pressure (check with mechanical guage)

-Low compression (check with guage)

-Mechanical failure (at high mileage even if you have a bad valve, etc. go ahead and rebuild the motor).

-Oil Analysis (you can send a used oil samplel off to check for metals that indicate a failure is near)

Thx-Ace