Question to all you Jeep Experts?

wow!! awesome post about your findings. crazy about the cats too, being blown clean in one and forced into the rear cat.
 

I found that removing the left from wheel and accessing the bolts through the inner fender was pretty easy.

That is such a good idea, I wish I had thought of it. I just struggled underneath with a bunch of wobble extensions connected together.

I'll know for next time I guess.
 
That is such a good idea, I wish I had thought of it. I just struggled underneath with a bunch of wobble extensions connected together.

I'll know for next time I guess.

You could reach from underneath with extensions. I replaced the cats snd spring clips a few times. But removing the fender will make it easier.


Never look down on anyone unless you are helping them up - Jesse Jackson
 

I will attempt to up-load some additional photos via the app, as via computer is a hit or miss!


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Id love to see the valves. I find it hard to believe that you didn’t have constant misfire if the valves springs allowed back flow. At a min a lean O2 code from the upstream O2. What valves, intake or exhaust? How did the cam lobes look? Also #4 compression was good no sign under compression. Leak down might have caught this.

So you didn’t throw any O2 codes?

When my CAT went/failed similarly (one missing). I threw codes P0431. Then when pulling the O2 it looked beaten and flattened on one side.
You didn’t have any O2 related codes? Or exhaust leak codes? Or lean codes?


Never look down on anyone unless you are helping them up - Jesse Jackson
 
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Never any 02 codes, not a one!
During all of the different codes being thrown, only one time a PO175 appeared.
No exhaust related codes.
Cam lobes all look good.

I'm thinking that the springs being compromised were not closing the valves fast enough at the higher RPM and power settings? I don't have the ability to test the spring tension, although there is a noticeable difference between the new springs and the springs removed, enough to be felt with your fingers. A dial indicator was used to measure the length.
I could drive around town for hundreds of miles with no issues.
Excessive heat will damage springs? I was having temp issues.

I am working with Terry trying to get additional photos up-loaded. I have chronicled this project with photos step by step. I tried up-loading via the APP, No Joy!

Thank you for your continued support.
Andrew~
 
The orange tab under the radiator cap is a reminder to self that coolant has been drained!

IMG_1893.jpg
 
Never any 02 codes, not a one!
.
Excessive heat will damage springs? I was having temp issues.

Andrew~

I’d think cylinder walls would be more affected by high coolant temp than a valve or spring.
However the heat of an exhaust valve not closing on the compression stroke will heat the valve and melt it. This happened in my Honda. PM valve lash was not on the checklist but there were TSBs for it once the valve failed.


Never look down on anyone unless you are helping them up - Jesse Jackson
 
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This is the fitting I silver soldered to the fuel rail for the fuel pressure gauge

IMG_2074.jpg

IMG_2076.jpg
 

Nice.

I have had cats like that. They flow way better when all the broken stuff is out
 

All back together, running like a champ. Out on the highway easily accelerates to 80+ MPH. Will take it out for a 200+ mile run later in the week. I think there is still a hint of knocking which I think is the crank moving fore and aft due to the wear at the thrust bearing.

Thank you again to all that chimed in with guidance. Much appreciated.

Andrew~
 
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