1988 Wrangler - Engine replacement advice

[trekker1701]

Greetings All!

I have a 1988 Jeep Wrangler and am looking for suggestions on engine replacement. It currently has the standard straight 6 258 w/ a Weber carb. The current engine has about 130,000 miles on it and burns, leaks oil, and sucks the gas. It also has the stock automatic transmission and transfer case. I currently do not know which models they are, but if it make a difference I can find out.

I am not looking to make this a rock crawler or anything more than a daily driver. It currently is 99% stock (has larger tires and leaf spring helpers installed). I also normally tow a trailer for camping, etc. I have been looking at replacing with the same engine, (obvously this would be the easiest) and others have suggested a small block V6. I do not want to spend an arm and leg for the swap but also want a good strong engine.

Any advice would be greatly appreciated! Thank you in advance for your suggestions!

-Eric

[AZXJ]

rebuild the existing motor.. Save you lots of time and money.. Or we have a 4.3L V6 for sale $1200.00

[RufftyTuffty]

A 350 would pull that trailer nicely :D

[OlneyJeeps]

over in another thread ademstr is telling Cjcarl how you could get a whole good drivetrain for $150:eek: .....if that's market, I'll take 6

I have heard the MC2400 (2bbl used on wagoneer 360's) works Great and is only a couple hundred dollars, easy install and will run almost upside down

[trekker1701]

rebuild the existing motor.. Save you lots of time and money..

What can I expect a decent rebuild to run and how long do they usually last?

The guy I bought it from thinks the engine had been already rebuilt. Is there a way one can tell and does that change matters?There is an issue with the gap on one of my plugs closing (does not do all the time) and I was told that the piston could be hitting it. Would this also deter from doing a rebuild on my existing engine? I'm great with a wrench and I have not problems with R&R, but when it comes to the inner workings I am kinda ignorant:o

If the rebuild of my engine is still do-able, any suggestings on a good mechanic in Tucson?

-Eric

[OlneyJeeps]

plug issue: are you sure you have the right plugs

engine: things to check.... compression, oil pressure, noises?, does it burn oil?

[trekker1701]

plug issue: are you sure you have the right plugs

engine: things to check.... compression, oil pressure, noises?, does it burn oil?

Yes they are the right plugs. Have not noticed any noises. Oh yeah does it ever burn oil!!! Usually go through 2-3 quarts a month (has some leaks too). Oil pressure at idle is usally around 40 and at 45-55mph it usually runs around 60-80. Sometimes is runs lower but not that often. I have not check compression myself, but a mech told me it was fine.

[ob1jeeper]

I'd bet that rather than it burning the oil, it's leaking it out. If it was burning that much oil, IMHO you'd be running around wiht a cloud of smoke behind you. The 258's (4.2L) were rather notorious for thier valve cover leaks. But that is easily corrected with a good cleaning of the mating surface and the application of a 1/4" bead of RTV.

These motors are EASILY good for 200K, if properly maintained...

Like has been said...

Cheapest = rebuild (long blocks run aprox $1000, then you install... even a moderately skilled DIY'r should be able to swap out a long block in a weekend, with the help of a buddy for the heavy stuff.

Best = Needs better definition, as you've already seen... Best is wide open to opinion, but a swap of a 4.0L would be pretty high on my list, for the ease of the swap, and the "relatively large" quantity of them available. Significantly more power, and should provide approx 16-18 mpg, depending on your driving habits. If a 4.0 is on your list, start shopping wrecking yards for a COMPLETE package, including harness and computer required to run them.

Whatever you do, I would caution you about FULLY checking into the hidden costs of a swap to another brand motor like the 4.3L V6 Chevy. Any motor swap other than another 4.2, or possibly a 4.0L, is going to lead to expenses that you don't see coming at you originally... such as: Motor mounts, exhaust systems, drive shafts, trans-t/case adapters, radiators, steering hoses, wiring, etc., etc., etc... Could cost as much as $2500 in hidden costs for materials alone, depending on how exotic you go, or lucky you get with your purchases. If your skill set is truly as you've described, then much of hte fabrication of components such as motor mount fabrication and installs, etc. may be over you head, and require that you end up having to pay a professional to do it.

[trekker1701]

[QUOTE=ob1jeeper;157767]I'd bet that rather than it burning the oil, it's leking it out. If it was burning that much oil, IMHO you'd be running around wiht a cloud of smoke behind you.QUOTE]

There are times where I have my own person smoke screen thats for sure, but it does not do that all the time. About 75% of the time I am tooling down the road with little or no smoke (that I can see anyways) but the other 25% I really feel sorry for the guy behind me! :eek:

I really do not have that big of a puddle under my vehicle after sitting parked, overnight, there is only small drops here and there with about a 2" spot in the middle. It is not pooling by any means, so I can only assume it is going out the tailpipe and I am not noticing.

I would prefer to go with the 4.0 so I can have the fuel injection. If I were to get one, is there issues with the tranny and transfer case? Should I take the whole set or will the engine just bolt up to my existing drivetrain. Right now the tranny and 4x4 works great with no probs what-so-ever.

Thanks for all the info!

-Eric

[ob1jeeper]

FWIW: it can still be smoking if the oil is gettino on the exhaust when leaking out. Is the back half of your motor, and the transmission bellhousing dry, or is it wet with oil? If it's not dry, I'd bet dollars-to-donuts the valve cover is leaking. Before I'd tear it down to fix oil burning, I'd make SURE it's not just leaking out, and that infact the smoke you see is coming from inside the t-pipe...

As for direct 4.0 swaps, there's literally hundreds of threads on various forums discussing this very swap, in fact there is one here about swapping a 4.0 into a CJ going on right now.

I'd suggest you take a couple weeks out, to do a little research on this topic, then knowing what you're seeking, go looking for the parts...

Good Luck...;)

[YGOHOME]

Ask Hackle... I think he just swapped a 4.0 into his 88/89 YJ a year or two ago.

[OlneyJeeps]

from what I've heard, hackle is also very mechanically inclined and has resources to do such a swap. I would highly recommend you do cost benifit analysis: what's it gong to cost (including your time) vs cost of early 90's YJ (already with 4.0) minus what you can sell your YJ for. Unless yours is real hunk of junk (which would net you hunk of junk with good motor after conversion), if you spend a little time you can probably do upgrade for under $1000 (with no grease under the nails:eek: )

just my .02

sidebar: does it blow smoke mostly when you start it up? If yes, is sign of worn/hardened valve seals.... try some CD2 additive... works wonders for about 3-6000 miles (then you have to ad another can)