Well, the day didn't go as planned....

[PacificEd]

I received my packages from 4 Wheel Parts today with my bushings and rebuild parts for the Rubicon Express front control arms. I did goof on the control arm tool. Apparently they build three different ones and I ordered the biggest. The RE3773 won't work.

 

[PacificEd]

Okay, well......today didn't go so well either.

Coopman82 came by and we started removing the oil pan. We noticed large amounts of RTV had been used. We also found out why. The edges of the oil pan were all bent and wavy besides the fact they didn't bother to scrape off all the previous gasket material. The stuff left behind is as hard as rock and doesn't want to come off. No biggie, just some time, right?

We then decided to change out the rear main. We removed the bolt and pulled of the rear main bearing cap. what we found made me feel sick.

So we decided to push out the upper shell to see what it looked like.

The upper looked way worse than the lower.

We decided to remove a few other caps and inspect them. One looked good and another looked like the rear.

So now I have to figure out what to do with this 300,000 mile engine.

The sad part is that I don't believe the rear main wasn't leaking. I think it was coming from the rear of the valve cover. Ugghhh!

 

[highspeed]

You got lucky then, since you found that out by accident. Could have failed on the street or trail. How does the crank look? Can you tell?

 

[PacificEd]

The crank looks pretty good, not perfect, but it looks better than the bearing. I'm thinking about sliding some new main bearing shells in to buy me some time while I look for a replacement engine.

The funny part is the engine has awesome oil pressure. Around 40-50 PSI cold and at least 15 PSI hot idle. I consider this to be great for a 300,000 mile engine.

You are right about finding it now rather than 5 hours from home at the top of a mountain.

 

[shortxjdoug]

Just slap it back together and run it until a replacement is found. I know where a good 99 short block is here in town

 

[RedHeep]

There's been some metal wear, but it's not excessive. If you want to feel better about it, put a bearing in it and put it back together.

 

[highspeed]

Since your there, check them all. Make sure those bearings are original size also in case there was some funny business before you got it, assuming your not the original owner.

 

[RedHeep]

The more you take apart something that was working fine, the better chance you have of screwing something up you shouldn't have been messing with in the first place.

Put it back together and forget about it.

 

[IllianaXJ]

^ This.

 

[highspeed]

The more you take apart something that was working fine, the better chance you have of screwing something up you shouldn't have been messing with in the first place.

Put it back together and forget about it.

^ This.

Wow! What?????

Removing the caps is easy and all you need is a torque wrench. I know I couldn't put that back together without peeking at the others.

I'll make sure to not let you guys work on my stuff!

 

[jeep ride]

Reminds me of the old saying if it ain't broke don't fix it.

 

[shortxjdoug]

Wow! What?????

Removing the caps is easy and all you need is a torque wrench. I know I couldn't put that back together without peeking at the others.

I'll make sure to not let you guys work on my stuff!

Why not? He wants to use it very soon and at 300k its probably better to refresh the whole motor at once. It runs so put it together and get some use out of it and tear it all the way down after.

I have depended on 4.0s in much worse shape.

 

[highspeed]

Why not? He wants to use it very soon and at 300k its probably better to refresh the whole motor at once. It runs so put it together and get some use out of it and tear it all the way down after.

I have depended on 4.0s in much worse shape.

Oh....don't get me wrong.....I understand getting every last mile out of it. I personally would stop and fix the issue though. I couldn't drive it knowing it was a ticking time bomb with a short fuse. More than likely all the bearings need to be replaced in both the rods and mains. It may run 100k more miles or 100 ft., you can't tell by looking at one main bearing. To each his own.

My z71 trans blew 3-4 clutch pack. It still drove fine for what I needed, going around town and to work......about 12 miles a day at 35-40 mph.....but I knew the reliability was about to decrease exponentially, so I parked it, pulled the trans, saved the hard parts by not continuing to drive on them, and rebuilt it on my own over the course of a few months. Just put it back in the truck this afternoon.


I'm just saying that a further inspection of all the mains seems necessary, that way you know what your up against and can figure out a timeframe of reliability. Assuming it will be fine is further than I would like to go. Your only talking about an extra hour or so, and Im sure Ed can use a torque wrench.

 

[PacificEd]

I have looked at the bottom shells of 3 of the five mains (and the upper on the rear). One looked good and the other had some scarring like the rear, just not as bad.

I have a Renix engine in the shop that is complete so I am going to take a look at it and see what kind of shape it's in and then make a decision.

 

[IllianaXJ]

Wow! What?????

Removing the caps is easy and all you need is a torque wrench. I know I couldn't put that back together without peeking at the others.

I'll make sure to not let you guys work on my stuff!

That's funny considering what RedHeep does for a living...

 

[highspeed]

I have looked at the bottom shells of 3 of the five mains (and the upper on the rear). One looked good and the other had some scarring like the rear, just not as bad.

I have a Renix engine in the shop that is complete so I am going to take a look at it and see what kind of shape it's in and then make a decision.

Hate to hear it, but glad you looked.

That's funny considering what RedHeep does for a living...

Mechanic I assume? They can be the worst ones!:cheers:

 

[RedHeep]

Hate to hear it, but glad you looked.







Mechanic I assume? They can be the worst ones!:cheers:

I'm the quality assurance chief for an aircraft maintenance department that is responsible for the safety of flight of 20 aircraft worth $1.3 billion.

My point is this: the wear that you see on the bearings has been replicated on the crankshaft journals as well. Because they wear together and the oil pressure is within limits, putting new bearings in doesn't necessarily fix anything. You may, in fact, disrupt whatever you've got going on between the bearing and the journal and make it worse.

You have an acceptable oil pressure indication, no indication of catastrophic failure and no other symptoms. Unless you're going to rebuild it, machine the journals, install new plus sized bearings and break it in, leave it alone. You can't half ass a bearing replacement and band aid whatever wear you have on the crank.

The person I am in the garage and the person I am in the hangar are obviously different. But I would NEVER give someone advice I wouldn't take myself or that I felt would cause failure or endanger someone or their family. To insinuate otherwise is insulting.

 

[highspeed]

There's been some metal wear, but it's not excessive. If you want to feel better about it, put a bearing in it and put it back together.

I'm confused. Which is it? Don't touch the motor or put ONE bearing in it and forget? See below.

The more you take apart something that was working fine, the better chance you have of screwing something up you shouldn't have been messing with in the first place.

Put it back together and forget about it.

I'm the quality assurance chief for an aircraft maintenance department that is responsible for the safety of flight of 20 aircraft worth $1.3 billion.

My point is this: the wear that you see on the bearings has been replicated on the crankshaft journals as well. Because they wear together and the oil pressure is within limits, putting new bearings in doesn't necessarily fix anything. You may, in fact, disrupt whatever you've got going on between the bearing and the journal and make it worse.

You have an acceptable oil pressure indication, no indication of catastrophic failure and no other symptoms. Unless you're going to rebuild it, machine the journals, install new plus sized bearings and break it in, leave it alone. You can't half ass a bearing replacement and band aid whatever wear you have on the crank.

The person I am in the garage and the person I am in the hangar are obviously different. But I would NEVER give someone advice I wouldn't take myself or that I felt would cause failure or endanger someone or their family. To insinuate otherwise is insulting.

For the record, I never said to replace the bearings. I stated that he should check them for wear and gauge the severity and longevitiy from what he finds. You can take bearings out check them without changing things.

Secondly, I have no ill intent by making a joke about you being a mechanic, it was simply light hearted poke. If you are offended or insulted, I am truly sorry, but I think you need to relook what was said, and by whom.

Lastly, I have stated my case......... look to see what else is damaged and make a guesstimate from there.

 

[PacificEd]

This is what it will look like when I'm done.

 

[shortxjdoug]

Valve cover should say 4.7