Inliners International Forums General Discussion Engines 151/153/181 or tech4?

Need to replace the engine in my 86 jeep. 151/153/181 engines will work I think?!- but what do I need to do? The 2.5 I have is a tbi engine. Should I do carbs or tbi?

If you're doing a bunch of real off-roading the TBI may work better for you because you won't have to deal with carb floats, if it's to commute back and forth to the bog town (Klamath Falls) either will work well. the newer 181 can be had with direct port injection.

KEEP IT SIMPLE AND CHEAP....... CARB

What model is your Jeep? What engine is in it now?Are you replacing it because it is worn out or because you want something else? What do you want it to do?

It's a 86 commanche with a 2.5 tbi and 4speed over drive 4x4. It won't hardly pull its self in 4th. goes faster in 3rd than 4th.

Here is a LINK to a Jeep forum that may be of some help. They are speaking Cherokee but I bet it holds for Comanches too. I've owned several Cherokees and Grand Cherokees. I had one with a 2.5 and a 5 speed and was impressed with what it would do. 2 had 4.0s and the present one has a V8. I like the inlines best.

If it was an earlier YJ that had a 151 GM motor I'd say jump on a 3.0-181. The 151 Jeep used had the same bell housing pattern as SBC and later L6, and the 153-181 Mercruisers. The jeep bell housing is aluminum and looks like a Ford on the trans side. It matches Mustang T5s. I don't know Jeeps that well but I have a 151 fron an'80 YJ that I have thought of putting in a Comanche. Let us know what you decide.

My other vehicle is a 2001 Jeep Cherokee 4.0. I had an 87 before too, 4.0. The first gen 4.0 (non-high output) should drop right in your Comanche, they came with it from the factory.. even an HO should work, considering all th eother things you need for the conversion. You would need the ECU too and various related bits and pieces. I bet the Cherokee forums would be a great help.
I'd be looking at a pre-95 4.0 and ECU. The later year ECU used the stupid CAN bus which makes transplanting harder. You'd need the whole instrument panel too and who knows what else, to maintain the CAN bus integrity. I don't know what year they started that.

Edit: back in the early 90's, I got a ride in a fairly new Comanche 4.0 in Venezuela. With 3 people in it, it really hauled ass! Must be much lighter than the Cherokee.

I presently own two 99 Cherokee 4.0 4x4 5 speeds,a 47 CJ2A and a 51 Willys 4x4 PU truck.All on road legal...
I had an 86 Cherokee XJ with a 151 four cylinder and that engine was AMC not GM.With a 5 speed and 4.11's it was damn slow but did the job

Thanks-I'm on the road right now heading to Gibbon,Nebraska then to Alphretta Ga. Visiting my daughters this winter. Looking to pick up a engine to rebuild while I'm on the road. the 2.5 in the jeep is really tired an it is the snow plow my neighbor and house sitter are using. Hope I can do it before she blows.

Well! Just got settled in Cummin Ga. now I can get back to a few of you. I,m pretty new with 4cyl engines, I've spent most of my time working on slant6 and some flat 6's. What was the 181 used in an did they have a cross flow head??

The 181 was and is mostly used in boats. Some industrial equipment such as fork lifts use them too. Some have 8 port heads but not cross flow. Later 151s have cross flows but I have heard hey don't flow well.

Beater: guess I'l go junkyard cruising the coming week an see what I can find here in Ga.

Here's a PAN but you gotta' hurry.