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

First off if you don't like longer videos, at least watch the last half of this video. At the bottom of this is the link to the first time working on this truck, It should make the story to this better. The truck has a rebuilt engine and after many many hours of diagnosing I found the problem but not the solution to the problem. Unless someone watching comes up with an idea that I am missing I plan on taking the engine out to find out what's going on.
• I Thought This Would B... First video working on the truck.

[@davidorr4457]

Those lifters are filled with oil and the oil sets the height. The oil on the lifter leaves through the hole on the side. You need to bleed the lifter. Loosening the lifter will make the valve seal but not fix the real problem. Since the oil pressure is slow to return to normal this indicates a possible blockage. Someone screwed up and did not fully clean the engine before reassembly and some dirt or shavings got in an oil passage. This needs to be fixed as it will cause premature engine failure even if you just shim the lifter to fix it. Shimming just removes the hydraulic part of the lifter so it works. The lifter is full of oil and too high but the shim hides this. That is a hack. People are saying shorter rods and that is the same thing as shimming. Bleed the lifter, if that does not work then you have an oil blockage that is causing excessive pressure in the lifter. Hope the bleed works If not then engine disassembly and clean, ouch.

[@locustvalleyfarms7241]

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

[@nickmcminn2137]

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

[@williamstamper442]

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.

[@thisguy7120]

I agree 👌

[@jimmyjckjones]

Not sure any of us here dislike long video's.. And this is super informative. So.. School is IN! Great vid as always IMO.

[@xjrope]

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

[@SGTRandyB]

Agree

[@johntagliente5969]

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

[@0151148]

Dex if they milled the head they probably milled the block to. The reason your getting proper readings with loose rocker arms is your creating enough slack for the push rod to perform properly with the lifters. You need to measure the block deck and see how much has been removed. Then order shorter push rods to compensate for the amount taken off the block deck.

[@tyleroneal5672]

You should measure lifter preload on each cylinder. If the block was resurfaced maybe it wasn’t zeroed properly in the machine and cut deeper on the cylinder one side of the block.

[@Greasy-hands]

True that

[@TechnicianRed]

You need to measure pushrod length with the Comp Cams pushrod length checker tool. Then order custom length pushrods if the pushrods are too long. This is a pretty common procedure in the GM LS world as they also don't have adjustable rocker arms. If I remember right an LS should have about 50-70 thou of preload in the hydraulic lifters. So just use the Comp Cam tool to take a measurement from the rocker arm to lifter with the lifter on base circle of cam and add your desired preload to get your desired pushrod length.

[@markdicicco6409]

Yeah measure the pushrods

[@killroy3607]

I think it could be a few possibilities! Number 1: bad cam/worn cam/ incorrect regrind Number 2: the block has been machined like the head (just like the piss poor job on the head...) causing the need for shorter pushrods Number 3: a combination of both number 1 and 2..... I would definitely pull the engine out, tear it down, have your brother check the block tolerances, and the camshaft tolerances! I personally think its number 3

[@killroy3607]

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...

[@frankshelton5330]

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

[@hunterswiski8398]

This is the best video yet dex it’s awesome the in-depth testing your doing to save this ole girl going thank you most shops would have just charged him for a whole new motor keep going with the longer videos and diagnostic 👍

[@twadam5218]

DEX I love your honesty and determination. Great critical thinking and troubleshooting skills. I hope you find an answer that satisfies you and the customer.

[@kevinbrewer9421]

Let me clear my comment up! Picture this in you mind . On an air cooled VW when they grind a hot cam for it they have to make the base circle of the cam lobe smaller to get more lift because the block doesn't have enough room for the extra lobe height. The lobe height has to be the same. So they make more lift by grinding the base smaller. Therefore you get more lift. If the base circle is to big it will bottom your lifters out.just a thought!

[@dexjs]

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

[@jeremyhanna3852]

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

[@jessiefugate8227]

I would check the cam shaft lift to see if they put a higher lift cam in. Since you have no way to adjust the rockers. It would be holding the valves open. Could still be bottoming out the lifter. Love the content. Keep up the good work.

[@davidchristensen2970]

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

[@edwarddavis507]

Drilling bushings instead of replacing them; over cutting the head; inserting larger valves to fit drilled bushings; that head is so out spec it’s a miracle that the engine ran. It occurred to me that the rebuild shop over cut the block too.

[@josegilbert8337]

Dax we love long videos u are a genius these youngsters need a role model like u bud keep teaching ur awsome we love u for everything u do

[@dexjs]

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

[@thomaswhetstone2870]

Love your videos bud. You pretty much covered everything I thought of. On the oil bleed off part I feel there could be a blockage be a plug in the wrong place or debri. You'll get it I have faith. Shared it with a friend maybe he'll chime in

[@dexjs]

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

[@taulbeeflory3614]

What do you think on oil flow? Restricted oil gallery or Misaligned bearings slowing the flow.

[@troylassalle]

Dex ,I want to compliment you on your persistence to figure this out . Most would have given up by now. Hopefully you figure it out so you can show us .My only guess is an oil restriction going to the lifter . But after 45 years wrenching you think you seen it all and then a new problem pops up . Keep making these good videos. It nice to see how committed you are to figuring it out!

[@lindamoser2532]

Dennis here. My opinion is, everything has a life span. Engines can only be rebuilt so many times before they are junk. Great Channel. My best guess is the cam. Have your brother build another block and get on with it.

[@SGTRandyB]

I watched every minute, and I’m back to watch again. Thank you for showing and teaching us. I have a newly remaned engine and it isn’t making the power you’d expect. Shop that installed thinks it’s fine. The transmission is also newly rebuilt and shifts perfectly, clean fluid after 1,000 miles. So I’m back to thinking something engine. But the oil is clean too. I’m gonna pull the plugs after this comment while I listen.

[@averagegamerguy7]

I love your content and I enjoy content that I can learn from. Longer videos are always my favorite but I also enjoy the shorts and shorter videos when you're unable to make longer content

[@tylerbuhite5432]

The content is so great, pretty please some more wrangler content? Just a sprinkle....from a life long PA jeeper. Thanks for all you do man !

[@freeidaho-videos]

Great video. Good diagnostic technique. If the block was decked, it can cause the same symptom. Milling the head and the block makes the pushrods too long. This can be mitigated by loosening or shimming the rockers, but the solution is shorter pushrods.

[@jeremyhanna3852]

Blocked oil passages in the Block not letting proper oil pressure to the lifters

[@Knucklebusta]

After watching the whole video, I’m most impressed with the GoPro light 😂

[@cbforme]

Maybe you should take that motor and double check everything the other machine shop could have touched. You could have a blockage somewhere in the oil return system due to poor cleaning of the block after machining. PS I enjoyed this video very much.

[@dexjs]

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.

[@beckybird5367]

I did watch both videos and the reason i watch your videos is because i know your very smart, and i know your gonna get right.

[@stanhamtree5054]

I had a similar issue The cam lobe was chewed up. It was holding the valve open at times and not at other times would check the compression. It would be perfect, then it was not.

[@johndavid6956]

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

[@nathanielposey8321]

Same here

[@jeremyhanna3852]

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

[@rustypotatos]

Long videos are great man it shows everyone what you are about

[@richardschultz2243]

After watching full video, it seems you are onto something with how the oil pressure seems to "drag" release. Is there any add-ons to the oil pump or oil pan? Maybe a upgrade that may restrict or minimize flow or backflow of oil? I have seen some Jeep forum chats about products that allowed for oil to stay in system to prevent "dry" starts? Just a thought to consider...

[@michaelweslowski2032]

Love the long videos man always look forward to seeing you post I love learning and Iv been waiting for this video to come out to see what it’s issue was keep it up man 💪

[@dexjs]

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

[@kidd7359]

The block got new cam bearings and didn't get the oil ports lined up

[@rickybobby7326]

That's very possible

[@dans_Learning_Curve]

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

[@kidd7359]

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

[@jaygraham5407]

Pull the motor

[@jaygraham5407]

I admire your determination

[@dexjs]

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

[@jaygraham5407]

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

[@WyattArnold9986]

Thank you for making an hour long video on this type of thing because I've been looking for a long video on xj work or mj work lol

[@rustedroostershop]

Pull the oil filter off and see if it makes a difference. It's a simple thing to do. Are the drain holes for the cam bearings lined up? Pull some oil galley plugs if it has them on the sides of the block. Gonna make a mess, but might find something.

[@Tpbmods]

Dex, I have seen this before and I know what the problem was in our situation. So my dad had this Ford 240 inline 6 and it did the exact same thing this is doing, loosening everything off a bit helped smooth it out. It ended up being an incorrectly sized cam that kept the valves just ever so slightly open.

[@jeremyhanna3852]

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

[@randywilkerson1251]

Agreed with the above.

[@arronhale280]

i watch all of your vids no matter how long

[@JimCountiss]

I am curious if they decked the block. That would add to the problem you have already got.

[@hughobrien4139]

I own a machine shop and have worked in this trade since 1990. I agree with your brother. Had already thought this before your drew it out on the drawing board. The valve stem lengths should be set with a straight edge over a stem length indicator in these situations.

[@hughobrien4139]

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.

[@SCOTT7CHEVY]

When you cranked it outside sounded like 2 low cylinders. A lot can do that, you covered a lot, but maybe even ring gaps lined up in 2 cylinders or something else simple like that.

[@scaletrailers80]

I love this kind of content! Sorry I can't help, you went past my theories other than LS swap!!!

[@Joe.Dillion]

Probably milled the block may need to check pushrod leangth Wonder if the checkvalve in oil pump is stuck

[@keithroverud2252]

Think about where this engine just came from. seems to me you could pull the engine, make sure all bearings are installed right oil passages are blown out and the cam measures up in less time than chasing your tail around. my bet is the shop that milled the original head assembled something wrong internally on that engine. love your dedication and work ethics.

[@jeffreymrrs150]

Put cam lobe down. Loosen the rocker arm and tighten to 0 lash. Then see how much it tuns until rocker arm bolt is tight. Its usually one full turn or less on preload. If its more than one full turn it might need to be shimmed to get in spec.

[@DustanBaburek]

I think your right on with oil blockage. 1&6 are last cylinders to get oil. I don't think lifters are getting proper oil pressure to self adjust. You said in beginning driving it got somewhat better. More oil pressure at higher rpm?

[@dexjs]

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.

[@dben13]

I'm not a mechanic at all and have no clue what half the shit you say means, but for some reason I can't quit watching..lol whether it's a 1 minute short or an hour long video. I do feel like I'm learning more and more though. So thank you for that! My wife drives a 2016 Jeep Compass right now, she has the 4 wheel drive, abs, and traction control lights on the dash. Pretty sure it's a bad wheel bearing that I can't afford to fix right now.. Lol

[@dexjs]

That’s so awesome. I don’t give myself credit but I see so so many comments like this. Glad you watch!! Sell it and get a 99-04 WJ

[@kidd7359]

I think the oil bleeds out the front of the camshaft onto the timing chain. The machine shop may have installed a cam button in the end blocking the port?

[@dexjs]

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

[@kidd7359]

@@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.

[@ericnelson6982]

I know someone else probably had the same comment. What about using adjustable rocker arms. I know it doesn't explain what is causing the problem. But you can adjust them individually and get the correct valve lash. The other unknown is,what camshaft is in the engine? Is it different than stock? More lift would cause issues. Has the block been machined? There is quite a few unknowns. It is keeping the valves open even before the lifers are all the way pumped up. there is a clearance problem somewhere.

[@sambo9535]

Question do you know if the block was milled down? If so that could cause issues causing the lifters to be in the wrong position and could hang open the valves when the lifters finally pump up! I would check the rocker arm angle!

[@prozz5664]

This sure is a weird one. I would check the amount of valve lift you're getting on each cylinder with a dial indicator, and compare it to another known good engine. It's possible the camshaft is worn. It could also be possible that you have blockage in the oil galley of the lifters causing low or variable compression. It probably wouldn't hurt to run the engine with the valve cover off, and watch all the rockers and see if they stay consistent or if 1 and 6 are dropping out. Hope this helps or gives you different perspective. Great content keep it up!

[@dexjs]

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.

[@davidlane9525]

Just a thought, maybe there mite be some trash in the oil galles keeping oil pressure from getting to let the lifters and come up where they need to be. Because if you losen up the rockers so it takes out the hydraulic lifters and then they do rite, or what they should be doing. Just something to think about. I'm not very smart when it comes to this stuff just anuff to get by. Hopefully you can get it fixed and let us know what you find out what it is. Thank you for the good videos and the information about this stuff that you have learned from experience you have got

[@dexjs]

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

[@zekehanscom5869]

Nice MJ full set of gauges. 4 wheel drive and manual transmission with bucket seats.

[@bill6872]

Bad cam shaft. I know it's new, but that means nothing like you know. Lobes might be off in cylinder 1 and 6. Idk.

[@LTCustomz]

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

[@bill6872]

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

[@hippiemiller]

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

[@Scott-wl2zh]

Wiped out lobes won't hold a valve open

[@bill6872]

@@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.

[@TheITSNOTGOOD]

I'm 1/3 way through your video and I'm just gunna say I miss working on cars every day because of jobs like this....to figure it out on the impossible are jobs I just love doing. Btw you're shop is awesome. Love the whiteboard room.

[@TheITSNOTGOOD]

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...❤

[@TheITSNOTGOOD]

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.

[@TheITSNOTGOOD]

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...

[@TheITSNOTGOOD]

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.

[@TheITSNOTGOOD]

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

[@dandahermitseals5582]

Is that A Comanche? I have an 87 metric tonne Dana 44 rear dana 30 front. Dandahermit. That click is characteristic on the 4.0 inline 6 around 150, ooo miles. Common solution is a new set of rocker arms and push rods. Dandahermit

[@Land_Raver]

The cam base diameter may be too large. The lifters are too high in the bore and not allowing oil to pass through or bleed past. That would explain the slow leak down. As someone else mentioned the later cams have a bigger base diameter. When you loosen the rocker its allowing oil through the gallery. Best guess, good luck.

[@lanebradford3235]

Look into the cam. Ide check to see if the cam is worn, ground wrong, or the bearings have gine bad. I think inwould also look into the pushrod length deeper. The motor obviously uad machine work done as you stated. Maybe it calls for a shorter pushrod.

[@nFlames2]

Had a shop grind just valves 2003 FORD F-150 4.2L V6 that I was replacing a burned valve on & I compounded them back in the head. Here in Bryan Tx. it takes 3-4 months to get a set of heads out of the machine shop. Sometimes just run them down to Houston that are just 2 weeks behind. So when I put it back together it ran fine till it got to running temp 220 then it had a miss. Once it cooled down it ran fine so I shimmed the rocker arms on 2 valves & that took care of the miss. I'm buying my own valve grinding machines so I can do it all at home. I have used them back in the late 70's in a Chevy dealership in Muleshoe Tx. for years. I have always done a 3-4 step valve seat job sometimes run the stones under the seat to open up the port.

[@justinchandler5436]

LOVE THE LONGER VIDEOS. I think the block is cut short like the head.

[@electroshreve5278]

Thanks for the video learned a lot you have loads of good information would love to see more videos where you expand on things further

[@dandahermitseals5582]

We had a toyota 3RZ with rear cylinder exhaust valve failing to seat. I grew up on the Mexican/ Texas birder and have seen motirs rebuilt there with wood dowl pushrods in them. I swear that's true.😮😮😅😅 Dandahermit

[@Formerlywarmer]

I said a few days ago check push rod length sounds like with all that leveling of the head they are most likely too long now which supports ur comment something holding the valves open slightly. This would lessen with heat to a point then get worse again as heat hit operating temp. Whoever did the head went too far on the planing it to square it up. Get a different head then tell the guy to get his money back for that motor and just get one with 140k miles on it and it’ll be fine

[@williamcullum6676]

I would find out where the oil that bleeds out of the lifter goes. Perhaps part of the rebuild process made the lifters bleed too slow. Could the valve springs be too weak? It appears the lifter plunger is over powering the valve spring. Is it true a lifter should only pump up to the correct height? When the lifters are empty they are short enough, so the root cause is somehow making the hydraulic lifter plunger over power the valve spring.

[@jaygraham5407]

Bum camshaft?

[@backroads_motorsports3531]

My money is on an incorrect grind on the camshaft that could possibly be exaggerated by the deck height. Only reason i mention the deck height is becasue it would affect the engine the same way the head that was cut too much. If it's only off by a few thousanths then it's only showing due to a deck surface that's had a lot removed from it.

[@dalebailey1844]

Additional did they put in a new camshaft. I have had one I put in and was milled incorrectly from the factory and we could not put a turn up in that eng. until we changed the cam shaft.

[@freedomfarms5960]

Possibly bad ring gap/ install or something to do with valve train I think your on the right track

[@davidchappelle6480]

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

[@freedomfarms5960]

@@davidchappelle6480 never know what you get with a reman

[@jonlape5620]

Oil passage definitely blocked... I've had this problem on my 96 I bought with a reman n it wasn't right. I did everything you've done and then some. Long story short I pulled the engine and had my machinist go over it. It was all wrong. Took engine back to the other shop n said have fun with your junk and I rebuilt my own engine with my machinists help. Problem solved

[@tsmith578]

Dexter,,, It absolutely seems like that engine does not have the correct length of pushrods. Hydraulic lifters generally are set up to run a preload of 0.060 more than Zero Lash. So figure out what the measurement is for Zero Lash Add 0.060 to that measurement and order a set of pushrods that length and install them and see what results you get from that Tim from Wisconsin.

[@pronounchecker]

38 minutes in... getting another cup of coffee. I gotta see how this ends!!!

[@jimmyjckjones]

Those push rods too tight on the cam? Starving the valve for oil? If you shim them it allows the oil to pass through, if you loosen them, the same affect.

[@heyinway]

Valve stems need to be shortened to match the amount removed from the head. Cam lobes are probably wiped out from not torquing the rocker arms properly. Too tight and lifter will grind the lobe diameter, ruining the camshaft. It doesn't take much to do that. Replace camshaft. By hand with a socket and ratchet on the harmonic balancer bolt...rotate until valves are closed on one cylinder...that piston to top dead center...verify carefully with 1/4" drive extension in spark plug hole. Then with a torque wrench tighten rocker arm to 21 foot pounds...do each cylinder this way. Just a fyi for another 4.0 issue with a manual transmission...a missed/abusive shift can cause the piston closest to the firewall to shatter below the rings. Farthest from the harmonic balancer, can't absorb the shock so piston breaks. Engine will have a deep knock...and will have good compression on that cylinder. Usually you can get by with pulling head and oil pan... unbolt connecting rod, push piston out of block. Usually it doesn't score the cylinder wall. assemble new piston and rings to new connecting rod. Clean the oil pump screen and oil pan, wash inside of engine with brake clean and spray with engine oil. Reassemble engine using a torque wrench.

[@williamcullum6676]

What if the engine deck height is way too short?

[@dandahermitseals5582]

Im 80 yrs old from the muscle car era. We built hp mechanically. Today kids just ad s chip. When we blue printed our mills we also dod a deck clearance as well as line boreing crank journals and cam journals. Plus cc matching chambers and flomerrucs. If you had adjustable rickers you could just adjust them. Those stock ones aren't adjustable.lucky for you your solution is mechanicke. Not a freakin computer. Did they do a mag/ flux test on those heads?? Dandahermit

[@tsmith578]

The only other reason that I could figure other than the pushrod length.. Would be that the camshaft has been ground incorrectly And the base circle on the camshaft lobes are too large Which would intern, not let the valves completely shut once the lifters are pumped up with oil pressure.

[@Land_Raver]

That's my theory too. Base diameter of the cam forcing the lifters too high and not letting oil past. That would explain the slow leak down as the oil forces past the lifters.

[@pisstoffcat5136]

That oil pressure thing is wierd , Edit ; generally the oil goes to the crank and rods first , then to the lifters , i wonder if you have a blockage or restriction somewhere, but none of that makes sense as it seems your lifters are pumping up too much and holding the valve open after adjustment. Can you get a oil pressure gauge on the lifter galley/circuit?

[@LTCustomz]

Wonder if they put the wrong cam in it when they put it together.

[@LTCustomz]

Renix 4.0 cam and non Renix. And even the wj cam are all 3 different. Lobe separation, duration, And the degree you install the cam.

[@jeremyhanna3852]

That's my bet 96 and newer cam in renix block or cam bearing in wrong

[@nathanchastain6004]

I have a zj that I bought with a blown hg that intake cyl 1 the lifter gets stuck in the bore. Sounds similar to what your fighting with but you can watch the rocker. Had me leaning towards cam. Take a dial indicator and see how much lift and sag that arm has

[@dexjs]

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

[@brantbuildsandoffroad136]

@56:57 in the video I noticed the compression only went up when you loosened the intake rocker arm of cylinder 1, it didnt do anything when you loosened the exhaust side. Double check cause that will at least narrow the problem down to that one lifter. Should also check cylinder 6. Keep the valve cover off and crank the engine or start the engine, and compare the oil coming out of the top of the pushrod/rockerarm with the cylinders that dont have a problem (this may get messy with oil) @46:52 in the video i can see the exhaust side releasing oil on the top but i dont see the intake side doing it but hard to tell with the camera angle. thatll tell you if there is an oil pressure/lifter problem. The only thing that would keep things stuck open to lose compression would be valve getting stuck, cam lobe/pushrod length issue, lifter not working properly. I dont think the valve is getting stuck, but im pretty sure its a lifter or cam/pushrod issue (yes i know you put new lifters in it). Not sure what they may have done to the cam to cause such a difference but after seeing the cylinder head machined way past what it should, i wouldnt be surprised by anything. Or its a botched block. when you took the head off you shouldve used your brothers straight edge and see how straight the block was cut using feeler gauges. but that would be my most educated guesses with the info i have. Good luck man, cant wait to see the next video about this thing.

[@Tt-yt7fo]

Hey dex love the channel I got a question my Jeep Wj with the 4.0 keeps bursting the rads at the seams, not where it meets the plastic but at the cooling fins upper hose area. My headgasket is good just tested that. What you think it could be?

[@TheReckless71]

Did you check the valve springs ? If they do not have enough tension to close the valves while lifters are under pressure then that is the issue .

[@rickjames6823]

Keep the long shop vids coming Dex

[@dexjs]

I was nervous releasing this one. Left a lot out.

[@eddiereichel9354]

I knew a guy who "knew what he was doing" He had a xj that wasnt running right. He said the motor was bad. He bought a motor and tore it all apart. He sandblasted all the parts and painted it and put it back together. Ran exactly the same as it did before he pulled it in. We figured out the fuel pump was bad. Put a new pump in and it ran for a bit more. Oil light came on. The oil filter was full of sand. The whole engine was full of sand from him "doing it right"

[@MrCornbread108]

This is probably irrelevant but hey never know, I had a short block built once before and the shop left a plug out behind the timing gear. I could get some oil pressure but never enough. I was stumped until I tore the engine back apart. Maybe not enough pressure is actually making it to the top so that the lifter function correctly. When you take some pressure off the rockers then it slightly flows. 🤷🏼‍♂️.

[@dexjs]

We wondered that on the front but #6 would be pumping out on the ground if it was out. But still possible on #1

[@rickjames6823]

Has to be the cam. That is all that’s left

[@Dino30ish]

Check the camshaft itself, wrong profile possibly ? . Maybe an issue with the cam bearing alignment for the oil issue .

[@rustypotatos]

Thank you and thank you Justin. You guys freakin rock!

[@pyrosuspect01]

Hey dex, The engine was thrown together by someone that obviously didn't bother measuring anything. I'm thinking piston height, should be checked. If you aren't getting a full stroke of the piston to the top of the bore you'll be shorted compression that leak down test won't show. I see it a lot in diesels with bent rods. If the person that put the engine together didn't order correct pistons or if the rods are short your compression will be low. Pull compression on all cylinders and compare.

[@pyrosuspect01]

The fact that they had multiple valves shimmed makes me believe they had low compression on the other cylinders as well. By decreasing valve duration you'll always up compression.

[@Timboslice2386]

If it was me I’d definitely check valve clearance and after that I’d check cam and lifters. Couple years ago a tech I worked with rebuilt a 4.0 and the cam ate up some of the lifters and some of the lifters ate up the cam lobes. Which in turn created a misfire and a tick.

[@Office_De_Receiver_Complaints]

Yeah Dex, this was dope af.

[@ed0c]

change the oil after the break in, use high zync to help wear the parts in

[@JohnnyJewMusic]

Your oil pump is too high psi possibly?

[@TrevByTheTon300]

Did you check fuel pressure??😮

[@JohnnyJewMusic]

Dude I think you answered the question right there or found a solution actually! Because the block and head were both shaved you're reducing the amount of oil that the engine takes . Change the oil pump

[@lanceraney3459]

I know your tired of hearing push rods. But it’s obvious involved due to the fact when you loosen rockers compression is excellent. How much decking did this so called machine shop do on the block? Is that way out of spec just like the head so therefore your push rods are never letting your valves truly seat. I hate to say it but I feel like the “new reman motor” needs complete tear down and go from there I hate it for your customer and said machine shop that did the work but it don’t look good with head being that far out of operating specs.

[@Scott-wl2zh]

Bingo

[@dans_Learning_Curve]

Wouldn't all of the cylinders be affected if it was a deck height issue? 🤔

[@blairgauthier7116]

Not if it's cut crooked

[@Scott-wl2zh]

@@dans_Learning_Curve not necessarily. It would most likely depend on exactly how the block was chucked up in the deck machine. If the tail of the block was chucked low and the nose of the block was high they may have angle cut the deck of the block. After Justine showed how much they cut from the head I would not trust the block machining till I pulled and disassembled the block to get a legit measurement across the entire deck from crank main centers to too of the deck

[@dans_Learning_Curve]

@@Scott-wl2zh point taken.

[@Jeff-j7o]

Just a long shot .Could the oil galley have an obstruction,? Metal shaving?

[@paulkaufman4901]

I’ve been thinking you have a bad cam grind but the slow release of oil pressure might be indicative of some blockage in the oil passages. Please tell us what you do to resolve this! I’ve watched both videos and I have to know!

[@insearchofadventure]

I would check the preload on the lifters and I would pull the cam and check it. If the issue isn't there it's gotta be the machining of the block

[@billsnow971]

I believe you are dealing with a block that has been over decked

[@TurboJeep]

Have u checked to see if the if the pushrod may have made a hole in the rocker. I’ve seen the push a hole straight through the rocker leaving a blatant miss on the cylinder where it happens.

[@jesseduke694]

Somtimes when a head is warped real bad they will heat it & straighten it before milling it. Think of ohc engines. The cam tunnul on top of the head has to be straight also. Plus you cant change quench by milling a head. You can change compression but not quench. But u can componsate for compression with a thicker head gasket.

[@larryburns4605]

Seen 4 cyl jeep similar problem got shims from Goodson machine shop supply shimmed each cyl to make even customer has over 50 k on engine now . Good luck

[@MarvGuerro]

If you are near positive on head specs I would take some material off pushrod by shortening it you'll make up the clearance

[@richwood8650]

Dex, Rich Wood here. You are going to be money ahead to swap engines. My guess same machine shop done work on the block as well as the head. First things first. Anytime you have an engine whose valvetrain is of the non adjustable type, any clearance changes such as higher lift cam, block deck height, or cylinder head deck machining, a push rod change is usually necessary. I've been a mechanic for over 40 years. You may have oil pressure issues. But there are larger issues here to deal with. Does it look like the rockers are getting enough oil? If so, focus on the elephant. I would be willing to bet, the same machine shop, bored,cleaned, whatever else, probably decked that block. If so, you are going to need the information of how much was taken off each, do the math and get shorter push rods. Good luck.