4.0 Litre that knocks. I need your suggestions!!!

[MrEleven]

I have a 1990 jeep cherokee 4.0L, 5 speed, 2 dr, a/c, and a wicked bad engine knock..fairly sure that it is a bent rod. Now the bent rod is not in question. I am wondering what to do about the situation. Now i live in nebraska and i want to either:

A: buy another 4.0L and replace it.
B: swap to a different motoR(IE...chevy 350)
C: rebuild the 4.0L that i have
D: sell the dang thing

"ALL" comments will be viewed as helpful.

Please help me out here. Now if it comes down to a rebuild should i have it bored out also...thanks everyone in advance. I am greatful.

p.s. not looking to spend more than $900 total

[gtmud]

You might be able to rebuild the bottom-end, but there is no way of knowing just how much damage there is till you tear-down the engine. ie. cylinder walls, crank condition. How many miles are on this engine? Yes I would,depending on the engines internal condition, look into bore it .030. That is a "standard" bore when rebuilding any engine. If you go the route of engine swap(4.0 to 350) consider all your upgrades, easily exceed 900.00. (Tranny,driveshafts, engine mounts, cooling upgrades, ignition) How-ever, an XJ with a 350 would be an awesome toy!! Good luck!!

[MrEleven]

Good advice it seems to me....I am very green when it comes to jeeps. I am in love with this one and would like to make it my daily ruff-rider. The motor has 170,grand on it and still has a great deal of power....the compression seems wierd on it. it jumps around alot. normally around 80 when i start it, then to 40 sometimes to 20. Also when she starts from cold, i am getting a horrible hesitation. it olny comes when i am rolling or idling at a light. It seems to lighten up when i press the clutch. Cant tell if it is oil pressure or idle air sensor, or fuel pump. Now the hesitation goes away after driving around for a bit and warming it up. ya got me on this one. GTMUD thanks for your input. hopefully i can get some more help on this matter... like i said i am in love with this 2dr beauty.

[MrEleven]

so are all cherokees XJ's?

[Saudade]

OMG... 80psi and then to 40 psi and sometime 20???? My '88 with 150K+ is still around 130psi.

Depending on your funds, I'd buy another 4.0, rebuild it and then swap.

[gtmud]

MRELEVEN,
With your compression fluctuating that much I would look into simply starting fresh, you'll keep chasing problems, and in the long run cost you more thatn you want to spend. get you engine block checked out, if its in good shape than I would rebuild it, and replace all your bolt-ons with new parts. Than you'll have something that will give you years af reliable fun. I have had plenty with mine. Tore the front bumper off after only owning it for a month. Than I bought a lift kit. Good luck.