Time for a new engine

[canon07]

My 1989 YJ with the 4.2 i6 backfires and stalls and has zero compression in cylinder 4.

The engine was rebuilt 3 years and 10,000 miles ago and hasn't really run well since. I think it was just a poorly done job but I didn't own it when the work was done and there's no warranty of any sort left on the work.

I'm leaning towards just getting a remanufactured 4.2 - it's the cheapest option when you consider all the other parts any sort of swap would entail.

I have been using her as a daily driver with maybe a dozen or so wheeling trips thrown in every year. I live about 4 hours from Moab and Sand Hollow is in my back yard so we do a little crawling. I took her to Moab a little over a year ago when I first got her and she did great on the easier stuff with he 31" tires and stock axles. I would like to eventually upgrade to 33s or 35s and do the Ford 8.8 axle swap but that's on the back burner now that I'm replacing the engine.

So my first question is, has anybody bought a remanufactured engine from Powertrain Porducts and how was your experience? I'm looking at this engine, 7 years on the warranty is what really has me leaning towards them: https://www.powertrainproducts.net/product/1987-1990/#year_make_model_part_engine

My second question is, will I regret not swapping when I had the chance? I've gone down the rabbit hole researching a TDI swap, contemplated the LS swap, and looked at prices on a 4bt cummins and they all seem like they will run me at least triple the cost of replacing the 4.2. Are they that much better than the 4.2?

I figure the TDi swap all-in is the cheapest swap option but even if I got a junkyard TDI that looks nice and runs great, a 7 year warranty on the 4.2 sure would make me feel a whole lot better than taking my chances on cheap engine. And with all the additional parts I'd need, it'll still be at least a couple grand more than the 4.2... although 30 miles to the gallon sounds way better than what I get now. But that would be a whole lot of gas I'd have to buy to offset the upfront costs.

Any thoughts would be appreciated.

 

[dodgerammit]

I did a 4.8 LS swap on my Wagoneer almost 3 years ago. All in, I was at $5K. That was fuel tank, AN fuel lines compatible with ethanol blended fuels, fuel filler hose, driveshaft (rear) engine ($1800 verified runner), transmission adapter ($500 since I'm rocking the 727), coolant hoses, PCM flash, and all the other miscellaneous bits. I did all the wrenching. I do plenty of vacations and road trips in it, so cost wise, it is justified for me since I can get Gen 3 GM engine parts anywhere. Most of the time the parts stores have whatever on hand for immediate purchase. Kinda nice if say the alternator or water pump craps out, I don't have to wait 3 days for their warehouse to ship something so I can get back on the road. I've logged around 20K miles since the swap. Just get in, turn the key, and go.

In a YJ, I'd consider a 4.0 swap before a LS, but that's just me.

 

[Stoopid Jeep]

You should remove the cylinder head and take a peek inside. A head rebuild and/or a new cam would be cheaper than a whole motor.

**edit
Actually, I would probably start with a leak-down test

 

[DOWNS]

I'd certainly start with some trouble shooting before replcaement but it sounds like it's been a problem engine from day one.

I Just ordered a TITAN Engines 2.5L for my dad as an X-Mas gift for him. Still not here yet, probably won't be here till after the new year. After the core charge, we were in the 2500 range I think. Shipping was basically free because they were running a promotion that knocked 300 dollars off.

 

[canon07]

I did a 4.8 LS swap on my Wagoneer almost 3 years ago. All in, I was at $5K. That was fuel tank, AN fuel lines compatible with ethanol blended fuels, fuel filler hose, driveshaft (rear) engine ($1800 verified runner), transmission adapter ($500 since I'm rocking the 727), coolant hoses, PCM flash, and all the other miscellaneous bits. I did all the wrenching. I do plenty of vacations and road trips in it, so cost wise, it is justified for me since I can get Gen 3 GM engine parts anywhere. Most of the time the parts stores have whatever on hand for immediate purchase. Kinda nice if say the alternator or water pump craps out, I don't have to wait 3 days for their warehouse to ship something so I can get back on the road. I've logged around 20K miles since the swap. Just get in, turn the key, and go.

In a YJ, I'd consider a 4.0 swap before a LS, but that's just me.

When hunting for a 4.0, do you need to get the OBD1 engine? Or can you go all the way up to an '05 Wrangler to find a donor? Is the reprogramming that much of a pain on the OBDII?

 

[machoheadgames]

When hunting for a 4.0, do you need to get the OBD1 engine? Or can you go all the way up to an '05 Wrangler to find a donor? Is the reprogramming that much of a pain on the OBDII?

You can use up to a 1999 TJ engine or up to a 2001 XJ engine. The XJ was discontinued after 2001 and the TJ changed blocks for 2000.

Only problem with an OBDII motor (96+) is that the cylinder head is not drilled for the temp sending unit that runs the YJ gauge, so you'd either need to use a tee to install the sender up at the thermostat housing, or you'd drill and tap the head. Or just get an older motor.

For the record, I am saying all of this with the intention of you installing the YJ stuff on whatever engine you choose and running it OBDI. Between the different fueling different wiring harnesses, I would stick to OBDI and not try to do anything OBDII.

 

[dodgerammit]

For the record, I am saying all of this with the intention of you installing the YJ stuff on whatever engine you choose and running it OBDI. Between the different fueling different wiring harnesses, I would stick to OBDI and not try to do anything OBDII.

In your case, since you have the 258 and would be swapping to a different motor, I second what Macho stated here and use something up to 95.
This unfortunately limits availability, but there are donor vehicles out there.

If you do choose this route, you will need the engine harness and pcm from whatever you get it from.
It will be more involved for sure.

The only real question is what do you want out of the Jeep? Daily driver would be worth the time and expense, imo.
Fair weather cruiser? Then K.I.S.S. with a remanufactured unit.

 

[YJ103]

Why does everyone install new motors when that time comes? Does anyone have the original engine rebuilt? I understand if someone is looking to upgrade engines for performance reasons, but what if your perfectly happy with the engine you have and it just gets tired? I have a 95 2.5 with almost 200k on it. The jeep is in great original condition and runs fine, but its a little tired. I only use it around town and to go to and from the beach, so I've considered just having the original motor rebuilt when the time comes. I garage it for the winter, so when that time comes I figured I'd just go through it have the trans done, too, as well as just a general refreshening of aged parts.

is there really a downside to just rebuilding the original engine?

 

[machoheadgames]

Why does everyone install new motors when that time comes? Does anyone have the original engine rebuilt? I understand if someone is looking to upgrade engines for performance reasons, but what if your perfectly happy with the engine you have and it just gets tired? I have a 95 2.5 with almost 200k on it. The jeep is in great original condition and runs fine, but its a little tired. I only use it around town and to go to and from the beach, so I've considered just having the original motor rebuilt when the time comes. I garage it for the winter, so when that time comes I figured I'd just go through it have the trans done, too, as well as just a general refreshening of aged parts.

is there really a downside to just rebuilding the original engine?

Only reason I could see is time/skill/not having a good machine shop.

I’d love to rebuild the motor and get it exactly to how I want. All of the reman sellers sell shortcut built junk. Doesn’t mean you’ll have a problem with them, but many do have problems.

 

[YJ103]

Only reason I could see is time/skill/not having a good machine shop.

I’d love to rebuild the motor and get it exactly to how I want. All of the reman sellers sell shortcut built junk. Doesn’t mean you’ll have a problem with them, but many do have problems.

I do like "original", so I think that I'd like to keep the original engine. But maybe add a turbo. Lol.

 

[dodgerammit]

Why does everyone install new motors when that time comes? Does anyone have the original engine rebuilt? I understand if someone is looking to upgrade engines for performance reasons, but what if your perfectly happy with the engine you have and it just gets tired? I have a 95 2.5 with almost 200k on it. The jeep is in great original condition and runs fine, but its a little tired. I only use it around town and to go to and from the beach, so I've considered just having the original motor rebuilt when the time comes. I garage it for the winter, so when that time comes I figured I'd just go through it have the trans done, too, as well as just a general refreshening of aged parts.

is there really a downside to just rebuilding the original engine?

I'm unsure where you get anyone said "new" motor. OP clearly stated he had the original rebuilt. It hasn't ran correctly since.
I had the same issue with my AMC 360 rebuild.
There are way too many hack jobs out there who call themselves professional.

And where does one find a new 258? A new 4.0? There are no such things.
They are all remanufactured. With a warranty.
In the case of those crappy professionals just mentioned who swear by their work until they eff something up, then they try to deflect and blame the customer before disappearing, a written warranty is very nice.
In my case, I did a swap. Not a new motor. But a running and driving powertrain from a donor.
Being able to somewhat safely keep up with traffic flow and find parts anywhere sold it for me.
I have no regrets. Purists can cope.

 

[YJ103]

I'm unsure where you get anyone said "new" motor. OP clearly stated he had the original rebuilt. It hasn't ran correctly since.
I had the same issue with my AMC 360 rebuild.
There are way too many hack jobs out there who call themselves professional.

And where does one find a new 258? A new 4.0? There are no such things.
They are all remanufactured. With a warranty.
In the case of those crappy professionals just mentioned who swear by their work until they eff something up, then they try to deflect and blame the customer before disappearing, a written warranty is very nice.
In my case, I did a swap. Not a new motor. But a running and driving powertrain from a donor.
Being able to somewhat safely keep up with traffic flow and find parts anywhere sold it for me.
I have no regrets. Purists can cope.

He also clearly stated that he was considering an LS or TDI swap. My question was aimed more generally at the perception that most people seem to be changing to upgraded/different powertrains, not necessarily "new".

I can find hundreds of threads that pertain to engine swaps or about people considering engine swaps, but few about people who just rebuilt what they had.

 

[dodgerammit]

He also clearly stated that he was considering an LS or TDI swap. My question was aimed more generally at the perception that most people seem to be changing to upgraded/different powertrains, not necessarily "new".

I can find hundreds of threads that pertain to engine swaps or about people considering engine swaps, but few about people who just rebuilt what they had.

Yes, but you said new. He didn't.
A swap isn't a new engine. It typically has plenty of miles under its belt, therefore is proven reliable via its mechanical history alone.

As far as why, I answered some of that already in my reply above.
But I will add, I can go into the parts store and get an alternator same day.
I can get a starter same day.
I can get any gasket (including a head gasket if needed) same freaking day.

None of the typical "well, we gotta check our main warehouse to see if we can get it.."
No tracking down a specialty vendor online, emailing to see if they have something in a dusty box on their shelf.
No relying on an aftermarket company to make a production run of a required part needed for your build only after they hit a minimum quantity of orders (here's looking at you Edelbrock, taking 6 effing months for a stupid intake that still had fitment issues).

Oh, and breaking 20mpg in a 40 year old Wagoneer when road tripping is kinda sweet.

Now, that that's out, the 360 and 258 are decent motors, but the all too painful reality was touched on by Macho concerning people who are actually capable of rebuilding these engines.
Couple that with parts shortages, or limited runs, or obsolete or dying aftermarket support (and this was before 2020-I began purchasing 360 parts in late 2018), and it's no wonder why people swap.

I have the same $$ invested in my swap as I did in parts and labor for the 360 rebuild. And a lot less headache and frustration since I am not the only one who did the swap, but am a growing community that is made of up of very knowledgeable and friendly people who aren't like a bunch of old men, angrily yelling at clouds when some newbie asks a question like so many purists can be. The aftermarket for LS swaps in many different platforms is strong. In the case of my Wagoneer, I was able to purchase everything to make my swap almost 100% bolt in. The only fab work required was drilling a few holes. All that was needed was a drill! No welding was required, though I am more than capable enough to do that.

And, we get to enjoy our rides. They do what we build them to do. Drive them for whatever purpose we cater the build for.

The 4.0 in my YJ is a nice, well kept motor. It should be an easy 250K mile plus engine. Aftermarket is there to a decent degree, I have no desire to change it. For now.
But even so, 4.0s around here in podunkville are trashed and worn out.
They are quickly approaching being out of production for 20 years. The 258s, 34 years. Feeling old yet?
I know of nobody whom I trust to rebuild it locally. Even if I should choose to do the brunt of the wrenching in that scenario, any gearhead knows aftermarket parts quality has went down the drain.

Do I struggle through like before, wait forever for shortages and delays? End up with more potential disappointment?
Or, do I find a running wreck and roll up my sleeves?
Maybe it's another low mileage 4.0, or maybe it's something else that's just as or more reliable.

 

[ytradio]

Yes, but you said new. He didn't.
A swap isn't a new engine. It typically has plenty of miles under its belt, therefore is proven reliable via its mechanical history alone.

As far as why, I answered some of that already in my reply above.
But I will add, I can go into the parts store and get an alternator same day.
I can get a starter same day.
I can get any gasket (including a head gasket if needed) same freaking day.

None of the typical "well, we gotta check our main warehouse to see if we can get it.."
No tracking down a specialty vendor online, emailing to see if they have something in a dusty box on their shelf.
No relying on an aftermarket company to make a production run of a required part needed for your build only after they hit a minimum quantity of orders (here's looking at you Edelbrock, taking 6 effing months for a stupid intake that still had fitment issues).

Oh, and breaking 20mpg in a 40 year old Wagoneer when road tripping is kinda sweet.

Now, that that's out, the 360 and 258 are decent motors, but the all too painful reality was touched on by Macho concerning people who are actually capable of rebuilding these engines.
Couple that with parts shortages, or limited runs, or obsolete or dying aftermarket support (and this was before 2020-I began purchasing 360 parts in late 2018), and it's no wonder why people swap.

I have the same $$ invested in my swap as I did in parts and labor for the 360 rebuild. And a lot less headache and frustration since I am not the only one who did the swap, but am a growing community that is made of up of very knowledgeable and friendly people who aren't like a bunch of old men, angrily yelling at clouds when some newbie asks a question like so many purists can be. The aftermarket for LS swaps in many different platforms is strong. In the case of my Wagoneer, I was able to purchase everything to make my swap almost 100% bolt in. The only fab work required was drilling a few holes. All that was needed was a drill! No welding was required, though I am more than capable enough to do that.

And, we get to enjoy our rides. They do what we build them to do. Drive them for whatever purpose we cater the build for.

The 4.0 in my YJ is a nice, well kept motor. It should be an easy 250K mile plus engine. Aftermarket is there to a decent degree, I have no desire to change it. For now.
But even so, 4.0s around here in podunkville are trashed and worn out.
They are quickly approaching being out of production for 20 years. The 258s, 34 years. Feeling old yet?
I know of nobody whom I trust to rebuild it locally. Even if I should choose to do the brunt of the wrenching in that scenario, any gearhead knows aftermarket parts quality has went down the drain.

Do I struggle through like before, wait forever for shortages and delays? End up with more potential disappointment?
Or, do I find a running wreck and roll up my sleeves?
Maybe it's another low mileage 4.0, or maybe it's something else that's just as or more reliable.

Ordered all the parts to rebuild my 258 this past summer from Summit and had them the next day.

 

[dodgerammit]

Ordered all the parts to rebuild my 258 this past summer from Summit and had them the next day.

You had better luck than I did, though mine was the 360 parts, so maybe there's enough CJ owners out there to keep demand up.
I still wouldn't trust anyone here to be competent enough to rebuild a toddler's Duplo set given the incorrect basic things I found going on with the 360.

 

[ytradio]

You had better luck than I did, though mine was the 360 parts, so maybe there's enough CJ owners out there to keep demand up.
I still wouldn't trust anyone here to be competent enough to rebuild a toddler's Duplo set given the incorrect basic things I found going on with the 360.

Yeah I hear you, I did the work myself, hard to find anyone interested in rebuilding. Everyone wants to install a crate engine.