"What's Wrong With This Jeep? What Will Fix It?" 

Yeah. Everyone saying to deck the block and adjust push rod size and this and that. It’s like putting a Bandaid on a bullet hole. It’s not a proper fix. I’m leaning towards what you stated above. Logically makes the most sense

Run the cyl leak down test after the lifter is pumped up should hear it out the throttle body

A hydraulic lifter assembly doesn't actually "set the height"...when assembled properly the valvetrain tightened down if non adjustable, there should be approximately .020 preload on the plunger below the retaining ring on top inside the body. Oil pressure will then pressurize the area below the plunger and effectively take up any clearance in the valvetrain for zero lash. Even adjustable valvetrains are the same deal with hydraulic lifters, on base circle of cam, use the IOEC method...when intake valve begins to open adjust exhaust valve, when exhaust begins to close adjust intake valve. To adjust back the adjuster off until there is clearance between pushrod and rocker. Start tightening that adjuster slowly until all clearance is taken out as you rotate pushrod with your fingers you will suddenly feel resistance. That is zero lash. Now turn the adjuster 1/2 - 3/4 turn. Depending on the threads of the adjuster about 1/2 turn beyond zero lash should push the lifter plunger down approximately .020 you can use a dial indicator to measure exactly .020 and most often is about 1/2 a turn, some are 3/4. This leaves about .030 left in the lifter until the plunger bottoms out. Most hydraulic lifters have about .050 plunger travel from retainer ring to bottom of plunger travel. If adjusted too tight or too far down with the plunger, lifters can "pump up" with increased engine rpm because of tolerances there is not enough time for oil to bleed off during each cycle up and down. This will hang that valve open and not good. That's pretty much what happened in the beginning of this vid, but for different reasons than simply adjustment. Some drag racers used to run their factory hydraulic lifters with the plunger near the top just nudging the retaining ring for maximum lift at higher rpms. However that method can cause the retaining ring to fail or even bend pushrods unless one checks adjustment often and keep that plunger just under the retainer. It's best to run hydraulics about 1/2 in most engines from my experience over the years.

I agree 👌

Keep these long and the funny one's shorter. You can't make any $$$ on the shorts anyways

Agree

What about that little cam positioning spring under the timing chain cover?

True that

You're not dumb like you say... your at a wits end with this thing and your not afraid to ask for help like some people are...

Thinking the same. Poor cam grind. Perhaps too much lift?

Yeah measure the pushrods

So far that’s been the best idea I’ve heard. Probably gonna have to pull the motor to check that but I get it. We will see

Right because it's a 96 and later cam stuck in renix block the base circle is different

I appreciate that! I’m learning what I’m doing. Thanks again

This was my thought too? Could the cam itself be bad?

Same here

Or damage to lifter bore and lifter get stuck sliding down some time

That's very possible

Or the bearing by #1 cylinder isn't lined up?

It seems like the entire oil gallery has very slow bleed-off. Might pull the timing chain cover and see if the oil is getting there. I mean if the engines coming out anyway

Pull the motor

Thanks much. I feel like it’s gonna come down to the oil pressure. We will see!

Glad you like them! My attention span sucks so I assume that’s how everyone else is.

I'm wondering if the other shop used a non renix cam.

@@robertlantero1053That’s possible, but wonder why cylinder 1 and 6 are the only ones affected.

Bad cam wouldn't hang valves open it would just have no lift

Wiped out lobes won't hold a valve open

@@hippiemiller My thought is that maybe those lobes for cylinder 1 and 6 are machined to the improper specs. Possibly too large? Idk how likely that is, or how that would even happen, but it wouldn't hurt to check measurements. I see what you're saying too though.

It’s like the base circle is too large or the pushrods are too long for the combination.

Thanks for the tip. I’m thinking it’s something to do with that. Possible cam bearing. Thanks again. I will follow up. Needed ideas from y’all.

The cam shaft base circle must be different. If someone has milled that much off of the head? what would stop them from going crazy when decking the block? I mention this because in general oversized pistons will be made with off set compression distances to reduce compression ratio for the over bore. Most of the time you end up with a piston .040”-.050” down. May not be the case but for sure a potential that will stack up and cause these issues. For now I’m saying it’s the camshaft base circle. At that point you’d had to get out the adjustable pushrod and set lifter preload with a custom length pushrod. I’ll also mention that those rocker arm bosses can cause a fight on a severely warped head and should checked for correction when using a straight edge to set stem height. It’s getting out there into over thinking but worn out 50 year old cast iron engine pieces can certainly put Justin into that realm. One real simple one that I got bit by many years ago was not cleaning out the rocker arm bolt holes. They were packed with debris and I didn’t chase the threads. Of course this was for our largest customer in that machine shop. He was also the best man at my mother and father’s wedding. So there were butt whipping rights in place. I think there’s a deck height issue with the block possible possibly a camshaft base circle diameter. Either way the pushrod lengths aren’t playing right with your efforts. Still yet, I am impressed with both of you brothers. You guys are diligent.

That’s legit exactly what I’m on to. If you cancel out oil pressure it all does perfect. Thinking you’re on the right track

I think that’s next step. I’ve heard few people thinking tha backside of the cam is cut too big. Thanks much. It’s a tricky one.

I think your right this is a renix engine with a 96 and later cam stuck In it with different specs it had the newer MLS head gasket has the newer vavle cover but it's a renix engine 91 and older

Agreed with the above.

Driving at rpm you it runs fine. Relatively same psi but at rpm It can’t loose enough air to not combust so it runs out ok.

Haha I’m just getting started. Only gave up on two jeeps in my life. Pretty sure

@dexjeeps I don't give up easily myself. I have proved International Truck dealer wrong. Took time and determination

I will definitely look into that. It bleeds out the cam front side. But where the oil comes from 🤔

@@dexjs there's a horizontal/front to back tappet gallery. From the tappet galleriy there's vertical cam and crank galleries, Multiple front to back.

That’s next on the list. Idk if dial indicator has enough travel but I’ll figure that out. Thanks much.

I was just think might have somethin to do with the rings myself !

@@davidchappelle6480 never know what you get with a reman

All those tools and you dont have a tool to hold the gas pedal 😅 sorry just picking...thats where I'm at now....im still in it...❤

And now you tell me your not looking for people to be funny my bad....im intrigued ill be right back let my brain soak on it.

Something is clogged in something...is why oil pressure isn't dropping straight down. Plugged oil filter...some shavings in the galley....plugged pick up tube...ill come back with more ideas in a minute...

The oil pressure guage of seal is pinched it could cause the pressure holding while leaking down and not in the motor...could need a thicker head gasket...ill be back still thinking.

Get another new head. That's my answer...