Jeep Liberty Rebuild!

[lynxer]

BREAKING NEWS

So tonight I was getting ready to get this party started and replace my engine. I have had a coolent leak that started with the water pump/coolent leak. The engine did overheat and then developed a miss. The jeep ran fine for about 10 minutes the next day and was shut down then replaced the water pump. Then I drove it about 15 miles and it started to miss and the temp started going up. I shut it down before it got over 3/4 high and came back an hour later. Started it up and miss miss putt putt. I checked the compression in all cylinders and cylinder 1 was lower than the rest (75 lbs) and I was almost out of coolent in that short trip.

So do the math

Overheat
coolent leak
miss
low compression

What would you say?

Head gasket!

After further reading, research and talking to my good friend that is a Jeep Tech I found that the 3.7 is known to crack hears at the sign of any overheating. Other than that it is a great engine.

So rather than doing a head job on a 200k motor I was going to throw a used engine in.

Well tonight I pulled the plugs out and checked the compression in all the cylinders. guess what. THEY ARE ALL GOOD! My plugs were all over due and I knew that. I had gotten a new set for the used engine for a fresh start. I threw them in (all 6) and took it for a spin (what did I have to loose?) It started to get a little warm and so I quick pulled back to the house and parked it in the shop. [insert frown here] As I was sitting back not looking forward to doing an engine swap I saw a steady drip coming from the Jeep. I popped the hood and searched. I found a little fitting on the front of the engine on the hose from the heater core (I think) was leaking. I pulled it out and the threads were actually rusted threw. It was leaking bad. It is actually a pretty standard part and I had a chrysler 2.7 sitting in the back. I stole one off of it and replaced it. Filled the Jeep back up with water and started her up. Let it run in the shop and get up to op temp. no leak. no overheat. no miss. I take it around the block a few more times drive it kinda hard see if I can get it to overheat. nothing! It doesnt overheat at all. So I come back to the shop check the fluid. Still good level. I then took it on about a 20 mile cruise. The thing runs great! It doesnt overheat and it doesnt leak fluid! I think it might live to see another trail! At this point I have nothing to loose and I am going to run it for a little while see what happens. I might be back on tomorrow night to tell you that it has a connecting rod through the block who knows, but it isnt leaking overheating and missing. There for I am not going to put the engine in yet!

I am sorry for the long story/rant/analysis, but I thought I would explain.

Boys it aint not over till its over.

say your prayers and live right maybe it is worth somthing!

Thanks,

-lynxer

I still plan to do the lift

 

[Powerslave]

Excellent... The engine doesn't tick or anything huh? If not, then it seems like you are good to go... Also, chalk this engine up to the HOW MANY MILES are on it, at 200K+ miles.

 

[tjkj2002]

After further reading, research and talking to my good friend that is a Jeep Tech I found that the 3.7 is known to crack hears at the sign of any overheating.

Any engine with a alloy head(s) have that issue and so does the pre-Vortec Chevy 350 cast iron heads(which crack at will for no reason).

 

[lynxer]

Excellent... The engine doesn't tick or anything huh? If not, then it seems like you are good to go... Also, chalk this engine up to the HOW MANY MILES are on it, at 200K+ miles.

Not a tick, miss or whistle. It runs like a champ. I just went out and started it again. I talked to my friend that is a jeep tech about it a little and he seems to think that maybe when it overheated it may have loosend up some carbon and caused a valve to not close completley or not seal and that would be why I didnt have good compression. He thinks it is a stretch, but possible. I have 196,500 miles on the libby. She will see 200k by November 1st. This weekend I am going to change the diff fluids and check out the rest of the rig for any other parts that need attn.

 

[Khaotic]

That hawt. Stories like this make me love my Jeep even more.

 

[HoosierJeeper]

Awesome.

 

[kb0nly]

Cool...

Hope it keeps going down the road! So the heater hose was leaking and after that no more overheating? Sounds like you might have gotten really lucky..

Oh i just noticed your a fellow Minnesotan don't ya know...

 

[04Liberty]

what all is involved in that? I have thought about it, but also thought about all the head aches that go with I am sure...

Many...from all the research I've done so far:
1. Need similar year 4.7 and trans and requisite transfer case, which means
you get 45RFE, but that's cool because the CRD's used it (plus
computers/harness)
2. More than likely customs driveshafts.
3. Front springs to handle the extra weight.
4. Haven't been able to compare mounts directly, but it looks like the 3.7 and
4.7 use the same mounts.
5. Radiator/fan modifications for extra engine length.
6. Custom exhaust.
7. Harness hacking/splicing!!
8. Probably a host of other crap I'm overlooking/forgetting.

Many people think the old 8.25 rear won't hold up to the 4.7's power, but I had one in a 72 Charger with a 360 in it (it was a beater). Never had a rear problem (904 trannies, on the other hand, aren't so robust as their 727 cousins).

 

[Marlon_JB2]

Why wouldn't the 8.25 hold up to the 4.7L!? That's dumb, it holds up to the friggin Hemi!

 

[JeepJeepster]

Does the hemi with the none quadra drive use the 8.25 marlon? Ive never heard anyone say for certain. I know the quadra drive is NOT an 8.25. Its an odd looking ring and pinion(kinda small). Funny looking spider gears too.

 

[Marlon_JB2]

I should have been more specific... the 5.7L Hemi. I believe the 6.1L Hemi in the WK uses a different axle, not sure which one.

 

[HoosierJeeper]

I should have been more specific... the 5.7L Hemi. I believe the 6.1L Hemi in the WK uses a different axle, not sure which one.

Maybe the 9.25???

 

[04Liberty]

Why wouldn't the 8.25 hold up to the 4.7L!? That's dumb, it holds up to the friggin Hemi!

Ummm, that's what i said, it holds up just fine....confused.gif

I should have been more specific... the 5.7L Hemi. I believe the 6.1L Hemi in the WK uses a different axle, not sure which one.

I think the SRT GC uses the rear from the SRT cars.

 

[Marlon_JB2]

The JGC SRT8 uses an upgraded Dana 44.
Every other engine (3.7,4.7,5.7) uses the Chrysler 8.25.

Glad that's over with, took a while to figure it out.