Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 12 of 12 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
1988 wrangler I6 manual, or as I call it, the money magnet. I will not go into what it cost to get the damn thing to pass smog here in California when I moved- but I’m probably one of a select few who have efi on an 88.

My beloved Jeep has become the “kids” learning car. Son was driving and he heard/felt a thud like running over a board. Jeep stopped and would not start. A fellow enthusiast towed him home, and ultimately got the Jeep to the shop. I was thinking the crank shaft sensor, possibly the coil, as it was still cranking. Mechanic started it in front of me, it smoked horribly, and you could hear knocking. His advice, purchase a new engine block to avoid the costs of searching down the culprit which was probably a valve or piston failure. The last engine I overhauled was a Chevy 327 maybe 20 years ago and I know little to nothing about jeeps. What can I expect in costs and does this diagnosis sound reasonable? I can do without any smart comments, like “you idiot, why didn’t you let him drive the minivan?” Or listen newbie, you ask such a stupid question when the real question is why did you buy a money magnet and take it to California to begin with?”

Finally, if I were to sell it as is, what would you value it at? It has zero rust, and outside of this mech issue is a solid ride.
 

·
Super Moderator
Joined
·
12,724 Posts
Welcome to the Forum 88snowleopard,

Without knowing the miles and history, your mechanic could be offering good advice.
I'd find out what a re-manufactured engine costs locally. Will you change it yourself as a learning project for your son or will you have the shop do it? If you have the space and the tools, you should be able to rent a motor hoist.
It shouldn't be too difficult to get an approximation of cost for installing another motor.

As far as the value of a YJ with a broken 4.2, we need more information and some pics. I think 5 pics per post is the limit, so a couple of posts worth of pics, a list of known mods and your assessment of miles and condition.

Replacing the current motor with a re-manufactured motor should be less expensive than buying another comparable Jeep. YMMV.

Good Luck, L.M.
 

·
Los Angeles
Joined
·
1,777 Posts
Where in California? The 4.0 engine in my Jeep was rebuilt by a shop in Oxnard. I looked up the reviews for the shop and looked good. I have about 800 miles or on it and seems legit. Invoice was at $1500-$1600.
It is California, you can find 2.5s 4.2s, 4.0s, LS all day long. Nothing is new, nothing is wow, and nothing hasn't already been done, lol.
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,971 Posts
Send me pics if looking to sell with toasted motor
 

·
Premium Member
Joined
·
2,476 Posts
As a fellow Californian I would be looking into kits to convert to Hemi or LS. Will be a little more than a remanufactured engine but much more reliable, robust, maintainable, and most important, smog-able.
 

·
Registered
Joined
·
23 Posts
As Luckymac says above, if you have space, tools and time it may be wise to research and consider your options before moving forward. I bought a project Jeep recently, since retiring, and it came with two 'unknown' engines, a short block (no heads) and a long block. Both Chevy 350 V8s (SBCs) and both engines are now at a machine shop for cleanup and assessment. It's a small investment to determine my next step - may end up with 0, 1, or 2 good blocks in the end. I researched and bought a handful of books on rebuilding the SBCs. The last engine I rebuilt was a 6 cylinder in a 62 Chevy Nova. Even if I decide to purchase a crate motor, it will be best to know the baseline on the two I have. The books can guide you through the tools needed, how to assess an engine to see if it's good or what's bad (i.e., compression testing), and how to pull and replace the engine or rebuild the engine. A quick Google shows many books on rebuilding the Jeep 6 cylinder. Best wishes for your decisions.
 

·
Super Moderator
Joined
·
12,724 Posts
I advised a 4.2 as a replacement because that's what OP has and it's as simple as it gets.
Most home mechanics should be able to do a straight 4.2 for 4.2 engine swap.

The next step is more complicated. That's finding a rusted or wrecked Cherokee that runs well. Since this involves everything that swapping a 4.2 involves plus cutting, welding and modification of the electrical system, fewer home mechanics are prepared to do this. The cost can be less if done by a home mechanic, but he ends up with a used motor. The cost can be significantly more if done by a shop.
It also involves removing the replacement engine from the Cherokee and disposing of the balance of Cherokee body.

Swapping in a Small Block Chevrolet motor is a third alternative. An aluminum block LS3 is a good start. Weight is close to a 4.2. In addition to what's necessary to swap in a 4.0. the swapper needs a conversion (adapter) kit to fit the transmission to the replacement motor. The cost will probably be quite a bit more because a wrecked car with a LS3 will sell for a lot more than a wrecked Cherokee.
Roughly the same thing goes for a Hemi swap.

It's considered best practice to have a complete vehicle as a donor. That way a person has access to everything that's necessary to create a running vehicle. Both the 4.0 swap and the SBC swap will require the computer and some wiring from the donor vehicle. There always seems to be something else necessary and if you have the complete donor vehicle, that "something else" is readily available.

If a person buys a long block crate motor the accessories will drive the cost way up.
GM might have a program where a person can buy a brand new ready to run motor but I haven't looked into the cost and availability of that.

Hopefully 88snowleopard will let us know what he plans on doing.
Offers to sell and solicitations to buy must be listed in the classifieds and a person must have 15 posts to do so.
PMs are OK anytime.

Good Luck, L.M.
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #9 ·
Hi guys- first, thank you all for the perspective and advice. I really appreciate all of it.

Step 1 was to work with the shop to find either a crate motor or a salvage motor. This has been a very strange experience. I called today to get an update and the reception kid told me they were having a difficult time finding a motor and second, jasper apparently doesn’t supply the motors- instead they take the motor you have and rebuild it. Clearly, the reception guy doesn’t have a clue, and why he is tasked with sourcing anything is shocking. He actually told me he located a “possible” motor in a salvage yard in New York but the costs were pretty high due to shipping... so, while the mechanics and owner have always been very fair and quick, this guy is a departure.

I am leaning to a crate engine but now have decided to try a different shop. I will talk with the owner tomorrow and would have done this earlier but I have been work traveling.

Also, thanks for the guidelines. How do I earn stars? I don’t think I am going to sell it just yet, but at the same time I want to respect the forum. I asked about value not to sell here but to offload it to someone in the shop. I wish I had the time to do it myself, and honestly I am getting that itch a bit. My neighbor is a collector and he has rebuilt many cars ground up and is working on an old mustang. He has offered to mentor and help, so I might end up going that route (pull the engine, rebuild it, then reinstall)

So in your opinion, is finding an engine tough? I looked via google and found all sorts of options.
 

·
Super Moderator
Joined
·
12,724 Posts
In Denver I found a few engine rebuilding shops simply by Googling. I read the reviews. There were one or two that I might have used if I needed another engine.
I was lucky enough to find a good rebuildable engine, so that's what I've begun doing. My current engine is pushing 200K miles and still runs OK, but it's time is limited.

If you live in a major metro area your Google-foo should compare to mine. The bonus is that if a rebuilder does the engine install, they usually have a longer warranty.
If you rebuild your engine yourself, it could take so long that you'll be buying your son another vehicle. Ask the rebuilding shop what their turn around time is.

Good Luck, L.M.
 

·
Registered
Joined
·
4,241 Posts
Road trip to Texas?

https://collinsbrosjeep.com/76-90-cj-yj-reman-4-2l-258-6-cyl-long-block-motor/

for many of us a swap to a "better" engine is the way to go. It is hard to beat the GM LS platform for a lot of reasons. In your situation, I think spending a little money on a good replacement engine is the way to go. You are likely to spend just as much rebuilding the engine that you have if it needs any machine work.
 

·
Registered
Joined
·
98 Posts
You can buy complete 4.0 engines all day long. I would swap it out. Once you get into that blown motor you might find that its too damaged to rebuild or at least very expensive to do it if the crank or rods are damaged. You're going to gain HP with a 4.0 conversion anyway, although you will lose a little torque.
 
1 - 12 of 12 Posts
Top