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Blew the 4.0L in my DD - Looking at Replacement Options (Cost is a Concern)

Jonner

NAXJA Forum User
Location
Charlotte, NC
zgyj.jpg

1998 Jeep Cherokee Sport
207K
4.0L / AW4
Dana 30 / Chrysler 8.25
Aside from the engine, the Jeep needs:
-New ring and pinion for the 8.25 (grinds on deceleration)
-New radiator (leaks)

Story goes like this...

Well, we had -30 degree temperatures yesterday and I was driving home from work at midnight. I started seeing steam pouring out of the drivers side front of the hood as I was about 2 miles from home. Check engine light went on, voltage meter went to zero, throttle felt like it was pushing the car forward more than usual or I had less brake vacuum boost (I think both). I came to an offramp close to home and attempted to put the rig in park. The engine shot up to 4000 RPMs so I shut it off.

I let it sit for a minute and opened the hood to inspect the damage. Everything was covered with coolant, and I had trouble telling where it originated. The coolant container was full to the top with milky coolant. The oil filler cap had whitish snot plastered all over it. I was able to restart the engine to limp it home. It was running rough but there were no nasty metallic sounds coming from the engine. I probably blew a head gasket, and might have blown a freeze plug. At the very least, the engine will need a new head gasket, new freeze plugs, and new gaskets all around (front and rear oil seals, etc).

I'm looking at replacing/rebuilding the engine. The motor could still be good, but it'll be a day before I can get it into the garage and it's still -10 degrees outside.

From reading reviews all over the internet, I want to stay away from a remanufactured engine (no ATK or Jasper). I think my best bet is to source a junkyard engine somewhere in Ohio, or pull the motor and take it to a trusted engine shop. I have no cash, just credit, so I'm trying to keep costs down but would like to get another 40,000 miles out of this rig.

Option A - Cheaper, quicker turnaround
So I'm looking for advice on sourcing a reliable 4.0L that'll work with minimal fuss in my '98. Right now I'm using car-part.com and Craigslist to find motors in Ohio. What years will fit without fuss? 96, 97, and 98???

Option B - More expensive, slower, but should be more reliable
I'd need to find an engine rebuilder I could trust close to central Ohio. I'm undecided about getting into every part's details, and would prefer to leave that up to the rebuilder but don't want to get screwed not knowing what to look for inspecting after the rebuilder is done with it. Any suggestions on trusted Jeep engine builders near central Ohio???

The bottom line is I need an engine on a budget and need to stay under $1500 for the engine. I still need to buy an engine hoist and engine stand, and some smaller specialty tools for the project. Anyone near central Ohio that has local advice? Or, anyone been through something similar and lived to tell the tale?
 
Call ATK directly and talk to them. Tell them you don't want the warranties, just the cheapest motor possible. I bet they will be able to get you one to your door for under 1500$, maybe a return or something.
 
Hell with car-part, that's a site that mostly caters to insurance companies and shops and the prices are mostly a ripoff.

Find your local pull-a-part. I can get 4.0s for $180 here, $250 with a 30 day warranty.

A 96 through 99 longblock will fit with no fuss no muss. A 91 through 95 will also fit if you either swap the front timing cover or cut off the part that interferes with the belt path using a dremel or angle grinder and (depending on the year, 91s and iirc some 92s and 93s are a different oil filter) swap the oil filter adapter over from your engine. Or just use whatever filter the donor requires, if it's a vertical filter it's the old AMC filter, Valvoline VO33 or equivalent, if it's the horizontal filter it's the Chrysler one, VO45, PH16, S16, etc.

I have never paid more than $160 for a 4.0, mostly because I buy them from local club/NAXJA members instead of going to the junkyard.

Keep the old block, purge the oil system as soon as you can, fill with new clean oil, then disassemble and determine cause of failure, as long as the block and head aren't cracked, you probably have a rebuildable engine on your hands. 4.0s are insanely tough when it comes to abuse, I poured thermite through 3 bores of one with 200k+ hard miles that'd been sitting in my yard for an entire winter with no head on it, full of water, and all the bearings were perfect, all the bores still had crosshatching visible, it'd been run for 10k+ with a badly blown head gasket between holes 3 and 4 and revved to the moon daily. The only way to kill one is to run it with insufficient air filtration/oil for so long that the bores wear out or let it spin a bearing/toss a rod through the side of the block. If I hadn't screwed up when I poured the thermite into one of the bores and caused stress cracking, I would have rebuilt that thing into a ghetto 4.5L stroker just to prove a point by now.
 
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Digger87xj - Thanks, if I wasn't already looking there I'd appreciate the tip. If it's expensive then at least it gives me the high end on 4.0L market prices.

go1lum- I had remembered great lakes when I was researching, then forgot, and now you reminded me again. I'll add that to my search list. Thanks!

Kastein - Thanks for the info! Do the pull-it-yourself yards usually require you to pull the engine yourself or do they have them stocked on a shelf somewhere? Also, if I rebuild the motor do you have any idea on prices?

My plan was to drain all the fluids (tranny, transfer case, oil, coolant - they're all due for new), disconnect everything connected to the engine, pull it, and put it on an engine stand. Then begin disassembly to assess rebuildability. Should I be worried about cracks that aren't visible that maybe a machine shop should check out?

If I don't rebuild it, then I'll sell it as a shortblock and head to make up some of the difference in cash.
 
I have no idea on rebuild prices, I've never done one, just torn down old motors I pulled.

You-Pulls usually want you to pull it yourself or pay a 100-150 dollar pull fee. Some of them have engine cranes or gantries and chainfalls you can rent/borrow. Others will happily send a loader out with a strap/chain to actually pluck the motor for you as long as you've already unbolted everything that holds it in. It really depends on the yard.
 
You're probably looking at $1000-1500 for an economy rebuild. If I were to rebuild a 4.0, it'd be 4.5+ liters. :)
 
You could do a basic ring and bearing job, or "freshen up" cheaper than 1,000. Lots cheaper, I'd think.
If the bores look OK, screwit, rings bearings & gaskets. Maybe a timing chain.
 
you can run a 91-98(maybee99)4.0 just gotta swap sensors and distributor, flexplates will even work should beable to pick up a used motor from a local for a decent price
 
Don't even need to swap distributor iirc, just the cam position sensor. At least I did that when I put a motor from a 96 (that originally came out of a 98 ZJ) in my 91.

The timing cover piece that has to be chopped off (or the cover swapped) is needed to put a 95 down motor into a 96 up because the belt routing changed then. Later timing covers simply don't have that boss.

And yes, a 99 will fit. 00 up nope, but they have a sucky head and are more expensive because they're harder to find in working condition anyways, so you're dodging a bullet by avoiding them.
 
Don't even need to swap distributor iirc, just the cam position sensor. At least I did that when I put a motor from a 96 (that originally came out of a 98 ZJ) in my 91.

The timing cover piece that has to be chopped off (or the cover swapped) is needed to put a 95 down motor into a 96 up because the belt routing changed then. Later timing covers simply don't have that boss.

And yes, a 99 will fit. 00 up nope, but they have a sucky head and are more expensive because they're harder to find in working condition anyways, so you're dodging a bullet by avoiding them.
i forgot what i had to cut, but i remember it was aluminum and i used a sawzall on it
 
markw - A stroker is tempting, but I'm trying to be realistic with how much my Jeep is worth. Market value is about $3100. A budget stroker build is around $1400 according to Dino's website and some information I've been reading elsewhere. I just don't know if that's a realistic estimate yet?? I've never pieced together an engine. I've sourced a complete engine and pulled/replaced but never dealt with building and piecing parts together.

yosarrian - I had a good knocking noise previous for the last 20,000 miles or so which I've read is common for the 4.0L. But I'm not sure if that means tapered bores, worn rings, or worn bearings? So I'm not sure how much of a freshening I would need?

I will be doing research to answer some of these questions, but I'm not sure how in depth I'll be able to get. Dino's site is crazy in depth and I need near a 30 day turn around since I'm driving my wife's car right now. So piecing together a build slowly over time isn't the best option timewise. That's why I'm leaning towards leave it to a builder or buy a used engine. If I could piece it together in 30 days and get it built, then I would consider it.
 
Jonner;246038589 yosarrian - I had a good knocking noise previous for the last 20 said:
Since you have to pull the motor if you are going to keep the car, I'd yank the SOB and pull it apart ASAP while you explore your options. You may find that it's worth hauling it to the machine shop. You may decide to do it yourself. You also might say "screwit" and buy a stroker motor. In any event though it couldn't hurt to get a good idea of your situation sooner than later.
 
Doubt it means worn rings, it probably means either a shagged out piston skirt or a worn rod bearing if I had to guess.

Before you give the motor a death sentence though (overheating and/or blowing the head gasket can't have helped, but they're tough) check to make sure your flexplate to torque converter bolts aren't loose.

It sounds like the motor should probably come out either way since you likely need to do some bottom end work and at least a new head gasket... you can do both in the vehicle, but by the time you do so, you may as well have pulled it and stuck it on an engine stand.
 
Yards here of the "we pull it for you" type get around $700 for a 4 litre. If the OP can do the work himself, his budget is well within reality for an installed used engine.

I agree with kastein, keep the existing block for a builder if you replace it. The yard will want a core charge but, they usually do not want all that much. Just the scrap value of the metals involved..

I also agree that the 4 Litre is tough to kill. It is well worth investigating what has gone wrong before pulling out the shotgun.
 
I thought ATK supplied stroker motors for Mopar... confusing that their over the counter 4.0 motors could be so shoddy.
 
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