Your First Engine Job - The Autopsy Begins On Our 4.0 Core, And We Start To Discover It's Issues

Reading the condition of an engine and it's parts is an important first step in the disassembly of an unknown core. We check the index of the damper, look over the valve train, inspect for external cracks and determine that the engine experienced a severe overheat by the state of its head bolts. An then there's that mysterious clacking noise...
#engines #classiccar #Jeep #autorepair #autoparts #diy
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[@spankyham9607]

See the thing I have always heard was you should still keep the parts in order because of the wear pattern over the years that develops.

[@sometimesleela5947]

And if you notice something weird later, you can go back and inspect the associated parts.

[@frankdmioli925]

I agree, Specifically the Lifters(Cam Followers).

[@lilmike2710]

Applies mostly to lifters where they contact the pushrods. And valves to the proper seat. But I think he's planning on a complete rebuild so all those parts will be getting replaced. And will likely re seat the valves as well

[@UncleTonysGarage]

That is absolutely true of certain parts (cam and lifters for example) and we've done many videos on the topic of wear patterns. This doesn't apply to things like the relationships between lifters and pushrods or pushrods and rockers. IF you can determine that there is an actual "wear pattern" there, it means the parts are finished and need to be replaced.

[@animalfarm7467]

Correct; it doesn't matter whether it's "Blueprinted" or not. Due to small variations across parts in contact wear, all parts develop their own wear pattern during operation. Unlike pressure fed components (e.g. big end) that are supported by a hydrodynamic fluid film, many components are boundary lubricated under negligible pressure and metal to metal contact is common in a wear-in period. Swap them around and another wear pattern will develop removing more metal from the interfaces during a new break-in period of high wear. In most cases, the parts will eventually wear into their new contact patterns, but in the overall scheme of things I prefer not to have high oil particulate loads when it isn't necessary.

[@ziptiesnbiasplies]

I wish you were a real hot rodder like DD speed shop!

[@sccarguy8242]

Yeah.. this is a rich man’s hobby, we have to spend all the money to enjoy ourselves. What’s with this any hack can so stuff shit?? Who needs that ?!?!

[@indianaslim4971]

I wish you could improve your vocabulary so watching one of your videos isn't like listening to a twelve year old trying to impress another 12 year old with the cuss words you know.....

[@termonostruman]

if yous ee amechnic taking aprts away and doing it fast without looking to it,, probably better get away from that guy

[@seahorse5677]

#1 Head bolt is the only head bolt that goes into the water jacket. This bolt is installed with sealant.

[@derekhobbs1102]

I thought about that, just like the Holden Red 6

[@stevenkirk2563]

253 and 308s also

[@colescrustycars]

This!

[@yamaha226]

Tony doesn't worry about that shit. Have you seen his work?

[@derekhobbs1102]

@@stevenkirk2563 Haven't played with them.

[@jamesdeans2614]

Let's watch a Tony in his natural element.... See how he's completely in tune with his natural surroundings. Although these older gearheads are e extremely hard to find in the wild, thier wisdom is up there with OB1 Kenobi. Cheers Tony from Perth Australia.

[@regularprepperguy6210]

Call me crazy. I'm 40 and like using hand tools over power tools, especially on classic cars. Makes me feel more in tune with the car in the time it was produced.

[@Piotr94L]

That's makes sense with cars build till 1930s-40s. Later all of them were assembled with power tools

[@12yearssober]

Except for wheels I'm the same way

[@mph5896]

Not me. I break stuff loose with a long ratchet if I can't get an impact in there. Everything gets spun in and out with the battery tools. Saves my body from carpel tunnel, and wear and tear.

[@Spike-sk7ql]

Maybe not crazy, but you certainly have a lot of time on your hands while working on cars. See, doing this stuff is how I make my living, and time is money. You don't get paid by the hour as a mechanic. You get paid by the job. So everything gets broken down with the fastest tool for the job. Impacts, and power ratchets, be it air, or battery power, were made to make life easier.

[@thisisyourcaptainspeaking2259]

Me too, and I've won or tied air tool vs speed wrench races. I might lose to battery tools if their battery doesn't puke on them...

[@mikedsautowerks]

These are the magical UTG videos I love. Step by step inspection, investigation and discovery. This is why I love working on cars. The autopsy of a machine is always my favorite part.

[@dtruth5769]

So awesome to have master Mechanic share his trade with us. Thanks Tony.

[@fomocoloco7172]

If I remember correctly the bolt that you said was suspicious was a bolt that goes through the water jacket and that's why it had that sticky sealant

[@jimmyguy428]

The classic cliffhanger! Well played, UT, well played! Your videos are pure gold so it's totally worth the wait.

[@bradsrestorations1085]

Tony, thank you for taking the time to do this on camera. I am learning from each video. It's a pleasure to watch someone who really enjoys what they do AND shares the knowledge they have.

[@carltotillo8301]

You can check the slack in the timing chain by watching the rotor movement on the distributor. It is better to check the timing marks with the head off.

[@spankyham9607]

This is one of those epic never die motors so it is interesting to see a tear down of this. These are usually a 500K mile motor with simple oil changes, an epic oil leaker, but never die.

[@Jaysunn00]

Mines at 210,000 it’s on at least water pump #3 I’ve put 4 headlight switches in and two ignition switches but motor is good only burns/leaks 1qt every 5000

[@tn2mich]

Valve cover leaks!

[@tn2mich]

I always keep the parts in order anyway. Might not be completely necessary, but great practice.

[@TayloJoe92]

Bought mine when it had 160k on it so no telling the care prior, but I did 2 oil changes a year and sadly mine developed a tick, then a loud tap around 195k. Engine shop said it was a bearing issue that made the piston misalign. Given what I know now after all the UTG videos I've seen I coulda saved me a ton of money and done it myself.

[@HILLBILLY_HARD]

I have to disagree, in its stock form and taken well care of they are a beast but you add a little power and an aftermarket camshaft you get a list of issues you don’t want to deal with!

[@sunnyray7819]

As a former 99' XJ Classic owner, I highly recommend putting in an RV cam. I wanted to do a 4.0 build to get just a little more power to where the thing wouldn't downshift to accelerate when I needed it. But a very reputable engine builder said I only needed the RV cam. Said he did one and it worked great, not downshifting on hills and a little more highway power. I also like the more round plenum intake, it seems to really help. I never had another 4.0 Cherokee beat me. I always lit them up. With 285's and about 5 inches of lift. All suspension lift. I had an Air-raid cold air intake and a flow master until I lost it one day jumping a bridge on a gravel road, long story short but it was actually quieter with it off oddly enough. And I played around with the spark gap from somewhere between 40-60. Not sure why I beat everyone so bad but that jeep did. I also put in an electric fan. The stock one is in the way working on stuff. Anyways, an RV cam can really make a 4.0. a lot better on the top end

[@kaboom4679]

They shrunk the exhaust valve in the 99+ heads to hear up the cats faster and the new intake design was their answer to get back the power they lost . Those 98 heads and their previous iterations have better low lift flow on the intake and that newer intake design will get you a handful of extra ponies with the earlier heads . Someone commented in an earlier reply about 4 hole injectors improving power and response . I have found that as well . An issue I saw where the motor didn't respond as anticipated to headers , a new intake etc .. , baffled a friend of mine , until he developed a bad mission #3 cylinder caused by a bad injector . I gave him a set of new ones off a bad motor .Not only didn't fix the miss , the motor , with over 200k miles , ran better than it ever had and is still running strong with just under 400k on it . The earlier heads also respond well to sensible porting work and 2.02 / 1.6 valves are a doable options , especially if you stroke it .

[@rriflemann308]

Instead of a screw driver to check for TDC, a standard wooden pencil is recommended ( to eliminate the risk of damage)

[@anthonysariol9307]

i learned the hard way when I was a young buck watch the rockers

[@MrTheHillfolk]

Thats fine and dandy until a hamfist breaks it off and its in the cylinder. Time to go fishing.

[@indianaslim4971]

I've only used screwdrivers, I know right where they are in my toolbox as opposed to rooting around for a pencil that's seldom used, it would take a special type of idiot to hurt anything while finding TDC by hand.

[@ricksshop]

This will be a great series. Too often people end up using garbage 'crate' engines. In the past you rebuilt what you had, and there was an entire industry built up around that (machine shops, parts suppliers). Sad how many machine shops have went under in the last decade. I love the whiff of dead dinosaurs when you crack a main cap bolt loose.

[@mostlyoldparts]

I wish I had a nickel for every 4.0 I've heard with piston slap. Great concept using a stocker and showing how to do a basic engine rebuild for the average Joe.

[@v12alpine]

I've torn down a few of these and currently building the nerve to put one back together so, perfect timing.

[@aprules2]

It's really a simple engine don't fear it

[@paulcabezola3559]

Bonding with your engine.........The Way Of The Gearhead Munk !!

[@sidewyndersshed1676]

I prefer hand tools for the exact same reason. You can feel each fastener, and many times it will alert you to a potential hidden problem. But, on a stock engine, even if I know I will not be reusing certain parts, I still like to keep everything in order. Later I may find an unusual wear pattern, or some minor damage that I missed. For me it's just a way to recheck everything. Awsome video series! Thank you for doing it.. 👍😁

[@ratt727]

Great idea using the ratchet to take the bolts off, I get the idea of getting a feel for how things are.

[@EnoreeAD]

The heads on the 2000-2001 xj's are the ones that crack. 0331 stamp on it. You need to get the 0331 heads from 02-06 that have TUPY stamped on them. TUPY heads are the better version, not prone to cracking. I just went through this headache. Pulled tupy heads from a 02 grand cherokee, and it's good to go. Your videos have helped me a lot! I have a 2000 xj that shattered a piston. My friend helped me rebuild a block from a 93 wrangler, and put the 2002 heads on it. Thanks for everything you do!! I appreciate how detailed you get in your explanations.

[@scotthay1486]

Great tutorial Tony. I appreciate you sharing your extensive knowledge with us untrained wrenchers. Stay safe buddy.

[@GTIwarrior]

UT that goop on the front head bolt is thread sealer. That’ one goes into the water jacket

[@jeremypike9153]

Make sure you have the cylinder head magnafluxed to check for cracks. The 4.0 had an issue with cracked cylinder heads on a couple of the castings. They were replaced a lot at the Chrysler dealerships usually it shows itself as a blown head gasket but after replacing the gasket it still has the same problem.

[@davecarey7452]

Episode 3. There’s an engine “Quincy, M.E.” in all of us. Can’t wait to see what’s under the head.

[@NewswithJakenator]

Shove an AMC 4.2 crank and rods in it. .5" incease in stoke. You will need a .5" spacer on the crank snout and larger fuel injectors if fuel injected but the end result will be appx. 4.6 liters using all stock parts except for the crank spacer. On my '89 Cherokee I used a 12 counterweight crank, a Crane truck power cam and Ford Mustang injectors (I forget which ones but I scrounged them out of a boneyard). The Jeep runs excellent and has gobs of torque all with stock parts except cam and split headers.

[@randywestrum6416]

Ahhh, a cliffhanger! Curious to see what’s inside. As a gear head and refrigeration mechanic, the same principles are applicable to semi-hermetic compressor tear downs. Awesome channel!

[@duke5171]

I hadn’t made the connection that loose bolts could mean an overheated engine; another good piece of information to keep in the bag, thank you. But I’ve always smelled the aroma of ripe fruit or mangoes when I take out head bolts from engines, maybe I’m crazy.

[@michaelgarrow3239]

Love your gear-porn Tony! I just pulled the head on my 232 and freshened up the valves. A lifter collapsed after almost 50 years 🙄but I still like my CJ-5 3speed and lockers get me around. 😎

[@kayoss662]

Your good at your craft. Mechanics and video creation. That one head bolt goes through the water jacket, gooped to keep from leaking.

[@HeppKattProductions]

I know it's difficult when you're working alone; however, some close ups on things like the timing marks / rocker arm positions would be useful for some.

[@jamesford2942]

Become one with the machine. Know it, feel it, commune with it. Later when you are driving it you will know if everything is right or not.

[@throttlewatch4614]

I’ve restored a couple motorcycles and I always say I’ve had a relationship with every part on that bike .

[@steveraus3495]

A CLIFFHANGER ENDING?!?! Dan was right. You're ruining hot rodding! Love ya, Tony. See ya tomorrow.

[@adamkreymborg3464]

Hay Tony your old school info is GOLD I love it.

[@raiderjohnthemadbomber8666]

Dwell is a serious measurement in point type distributors. It's a finer adjustment than setting the point gap.

[@Churchkey83]

Yup I'm learning things. This will help me with my 5mge.

[@scottladewig508]

I have a 95 Jeep Grand Cherokee with the same motor and I used to have a 91 Cherokee with the same motor they were notorious for bad timing chains. These things would go $300,000 mi with very little maintenance to the motors but they also had what always sounded like a rod knock. I've heard conflicting stories of what they actually are but even though it's just a light knock at idle once the oil's thinner but they still run and run and run. It's a very good motor. I've heard a lot of people say this is the Chevy small block of all six cylinders.

[@kaboom4679]

More than likely it is piston slap which is a known issue . Unfortunately , there are no aluminum blocks for this motor , not , any aftermarket blocks at all . Edelbrock did make an aluminum cylinder head tho . What would really be awesome is a cross flow head , but I doubt that will ever happen .

[@AtZero138]

Welcome to UTG "shop class" edition... I already said your welcome

[@rcnelson]

Zen and the Art of Engine Rebuilding.

[@debluetailfly]

I just used those same words in replying to another comment, then I scroll down and see your comment! Great minds think alike!

[@clutchkicker392ison5]

Funny how watching someone do something you've done a hundred times is still interesting, Cheers. Luv ya work.

[@georgebonney90]

Thank you Sir im getting ready to rebuild and old Chevy 350 for a truck and this helps tremendously

[@four-eight-zero5627]

I'm just getting to the end of my first 350 rebuild (pickup). Spent a LOT of money and it's only marginally better than factory. I look at it as paying for experience instead of interest payments going to some scumbag banker/car salesman.

[@alexlandsberger1423]

What i do is break them loose by hand then unthread them with a 1/4 impact. with the small impacts its usually pretty easy to tell if the threads are funny

[@hayneshvac2]

It is important to note that you should know the torque pattern of your heads, and to loosen the bolts in the reverse order of the torque pattern, this is more critical on aluminum heads, but there have been instances where cast iron heads have cracked as well...and it wouldn't hurt to purchase some thread chasers for future use when doing your clean up.

[@skylinefever]

I did not know that overheating destroyed compression by making rings stick to the ring lands. I thought it destroyed compression by destroying the heat treatment of the piston rings, then causing a lack of ring tension. Maybe both things happen? Have you read about the stroker combo you can make with the AMC 4.2/258 crank and the 4.0 block? 7:58 Yes. If it just has casting number "331" then do not use it. Assume it is either already cracked or will soon crack after rebuilding. Chrysler made them to stop the crack problem. If it says "331 TUPY" then it can be worth rebuilding. Later Jeeps got it, and some Jeeps had to have the head replaced at one time, and got a 331 TUPY later on. Clearwater Cylinder Head sells a replacement for the 331 head that is beefed up. Some people go for those. Other times, maybe someone gets lucky, and picks up a 4.0 long block core that already has a replacement casting. 8:48 Just search for any problems that are common for any engine you have. You had an interesting discussion about Buick fans and their oil related problems, for example. 10:48 There are two situations where this doesn't always apply. 1. Some crankshafts and crank bearings. Sometimes bearings are color coded in order to get the absolute ideal oil clearance. This is common in Toyota and Nissan engines. When rebuilding, some people order the same code bearing, but this isn't ideal. Take extremely precise measurements and order the correct code bearing if your crank can be polished up. If it can't be polished, then cut to the next undersize. Usually there are -.25mm and -.5mm bearings. 2. Some cylinder bores are measured, then fitted with a certain OEM piston. This is why you'll need to mark pistons if you pull them, rehone, then put them back. Also, this is good if you order OEM standard size pistons. Subaru engines are like this. 12:14 Yes, and it is even done on limited edition production engines. Guys put this much dedication into the engine assembly line of the ZL1 Corvette, AMG Mercedes, and Nissan NISMO GT-R line. 15:10 You will know if it is sealant if the service manuals tells you to use sealant there. Also, you will know if new head bolts have sealant already applied to that bolt.

[@Beanerds]

God damn Uncle Tony ! looking at you doing this on a 4L inline 6 of newer vintage ,, reminds my of my days of rebuilding the Aussie 215/245 and 265 ci HEMI 6 cylinder engines , super strong and only really die through lack of oil changes or those damn head gaskets ! I was always a 225 leaning tower of power rebuilder and lover and time moves on ,, the HEMI 6's are awesome ,, your 4L is a sweet tutorial , great engines and plenty will learn from this . Thanks Brother , many will learn from this series .

[@ronaldspins]

@ 15:00 is that bolt a water jacket bolt??? Loctite Head Bolt and Water Jacket Sealant 1158514 yes one penetrates

[@carllmack2287]

Yes, that head bolt goes into a water jacket and required thread sealant.

[@v12alpine]

indeed

[@merr6267]

That last cliffhanger sounds a lot like a TV show. Haha. After watching the authentic delivery of Tony and some other channels over the last few years, it's almost painful to watch some shows that are designed for TV with everything sponsored. Everything is product placement, plugs, spotlights, highlights, etc. I got no problem with parts and advertisement, but I'll seek out product advice from actual users with experience vs the 40 second shots of a guy pouring his "favorite" oil in. Haha.

[@alrui]

It's still good practice in general to keep the parts in order. That said I concur on the air tools, etc.

[@brianbrigg57]

Mean old Uncle Tony. Making us sit through the removal of the rockers then the head bolts and leaving us hanging. To be continued.............

[@anthonyjackson280]

A much more accurate way of getting TDC that I developed working on a 2.0L ford DOHC was to wrap some masking tape around the damper a few inches either side of expected TDC. Then use a depth measurement through the spark plug hole to set the piston at ~ 1/2 stroke either side (always with piston coming up). Mark the masking tape at those 2 points (adjacent to a fixed block reference eg the timing pointer) then measure and mark the 1/2 way point between those points on the tape. Rotate engine until that 1/2 way mark is at the pointer reference you used and piston should be bang on tdc. Locating the piston at mid stroke accurately is much easier than trying to detect the very small movement either side of TDC. Mid stroke it is travelling the greatest distance per degree of rotation. I had to develop this way as the Ford engine had no external timing marks, TDC was supposed to be located by inserting a 5mm gauge pin through the side of the block to enter a reference hole in the crankshaft. The plug for the gauge pin port was located directly behind the exhaust manifold ...

[@bullbutter2931]

Full Metal Jacket crazy guy putting rifle together 😂 Perfect !!

[@warmstrong5612]

Zen and the art of engine rebuilding.

[@user-up8sn1xv7k]

The Butter has slipped of yuor noddle! That is too funny Tony. I love it and thanks for the great info. My I also be at one with my engine.

[@kart70]

Not really pertinent to this video, but the thing UT did with the rockers to check for TDC is important for setting valve lash. When a cylinder reaches rock over (valves are open at the same time), its companion cylinder (its piston is at the same part of stroke as the first cylinder) is at TDC compression/power. This is when you want to set valve lash for that cylinder. To find out your companion cylinder, stack the first half of the firing order on top of the second half of the firing order. For example, a four cylinder firing order may be 1342. So write 13 42. This means that 1 and 4 are companion cylinders. This also means that even though there are no timing marks for 2 and 3, if you see number 3 cylinder in rock over, you know that 2 and 3 are close enough to TDC to set valve lash for the number 2 cylinder.

[@IOPOrt51]

The first bolt goes into the water jacket. the "gunk " is thread sealer. 515 Loctite works well.

[@jacobellis9820]

If memory serves me the 99+ heads were the ones that cracked really bad, but the intakes were redesigned with a larger plenum and more rounded runners and the factory exhaust manifold flows better. The earlier heads could still develop cracks usually between the valve seats and would seep coolant into that one cylinder. Pistons were bad about cracking on the 96+ where they redesigned them with shorter skirts.

[@kaboom4679]

They downsized the exhaust valves in those heads for faster catalyst warm up , to meet emissions . The intake and exhaust manifolds were redesigned to gain back the lost power . That faster warmup IMO contributed to the head cracking issue with the 0331 heads .

[@jacobellis9820]

@@kaboom4679 yep, it's been a minute since I messed with a 4.0 so I'm shaking off the rust on my memory lol.

[@kristoferfly9983]

Tony, I'm the same way. My friends bust my ass that I use hand tools, but same here, I like to feel the threads bringing bolts out etc

[@WiSeNhEiMeR-1369]

HOWdy U-T-G, ... Thanks for the "autopsy" on the 4.0 Core Engine COOP the WiSeNhEiMeR from Richmond, INDIANA ...

[@jeepxj1988]

That head bolt next to the number one cylinder exhaust port (I think the torque sequence calls it #11) gets less torque than the rest and thread sealer because it goes into the cooling jacket. That same head bolt and the one by the number 6 exhaust port can get into a fight with the nearby exhaust manifold studs if one is not careful.

[@orig66Super]

This is Great! I had coolant gush out of my upper intake so I emptied the van to get it ready for the salvage yard. Then I thought about it a bit more and took off the upper and lower intakes to clean the engine in vehicle. The engine looked like a Betty Crocker easy bake oven with chocolate cake mix inside.

[@doublek5583]

I rebuild a 4.0, a couple years ago, and was very surprised of how heavy it was

[@kaboom4679]

They are not lightweight components for sure . But it brings the torque from right off idle , just what you want in a low speed workhorse truck engine . It also will last forever with a little care and regular maintenance , and even if abused , will outlast most other engines , if only out of spite .

[@MoparMan-ff8fb]

I was told if you dont keep good coolant levels in in jeep engines especially 4.0 liters the check engine light will pop on ?? also you got to make sure the cooling system is burped of any pockets of air . other wise you can over heat the engine . also you can use a jeep grand cherokee clutch fan on the XJs to help them keep proper temps. Also I also read from an Jeep XJ forum they had cooling issues and before the engine was rebuilt they soaked it in a electrolysis bath ! it cleaned out the inside of the Jeep engine especially the coolant passageways and when they rebuilt and installed the engine and properly filled the coolant the engine never had anymore issues .

[@Rorschach1024]

Tony, whole you have this thing apart you need to replace the o-rings on the spin on oil filter adapter with viton o-rings. The shitty Buna-N ones from the factory get hard as a rock and leak.

[@snakeplisken2123]

We use oven cleaner from the bargain store to clean table saw blades. I was looking at it the other day wondering if it would be good for parts cleaning. Now it’s confirmed. I’m going to need this series for the 87 ford ranger I’m fixing up. The previous owner deleted everything possible including the break booster.

[@TAVOAu]

14:50 I had the same in my video pulling apart the Hemi 6, some bolts cracked loose, some not quite so tight, and one surprise bolt 😂

[@timothykeith1367]

Very often you can find a junkyard motor that only needs to be lightly honed, new rings and bearings. I recently got a $200 motor, took it to a automotive machine shop and they told me to use it 'as is" after they resurfaced the block deck. Look for evidence of sludge. A motor that is clean inside might not need any machine shop work. The ones to look for are grandpa's car that has been parked since he went into the nursing home, then he died and it sat for another decade in the garage. The motor I found had a new battery in the back seat floorboard, I figured nobody would get a new battery for a car that was running when it was parked.

[@lilmike2710]

I wanted to see what was under that head ... What a rip off. Deliberately stretching it out for content. 😁 Making us wait like that

[@doublek5583]

Casting # 0331, the word Tuby, was molded into the head

[@byghouse93]

Thank you man. This video is very helpful. I know you hate it but it’s great to see you wrenching on stuff.

[@classicwefi]

That one front head bolt gets tread sealer due it treads into the coolant jacket above the water pump all the other bolts tread into blind holes no sealer needed.

[@mikebougher3731]

Pretty much when they changed from a distributor to coil packs are the cracked head years.

[@skylinefever]

I didn't realize that was the difference. I thought in 2002, they introduced the 331 TUPY casting to solve it.

[@mikebougher3731]

@Skyline Fever I should have worded that different. I meant when the change happened like 2000 or 2001. The tupy head was the fix.

[@brendanlanigan6104]

00-01 heads pretty much always crack between cylinders 3 and 4, happened to me when I thought it was just a head gasket lol

[@junksautomotive]

Man I dig the breaker bar speed wrench! I've done the same. Old school!!!

[@kenleppek]

Oh the suspense is killing me!

[@tonypace2009]

I had to replace the head on my 2001 . Found crack after a overheat. The previous owner apparently instead of buying a vented thermostat or drilling a vent hole in thermostat decided to punch hole and in doing so bent the poppet cage so poppet didnt open enough and over heated at highway speed on interstate. The crack showed after running motor from wet spot between rocker bosses but after removing old head and it sitting for a period of time cant even see the crack now at least not with the naked eye. The one bolt protrudes into water cavity and requires a sealer that's most likely the one bolt with gunk on it. My girls 1999 has blown head gasket or cracked head trying to get her to save for posiably a new head havnt removed head yet . It got hot enough to melt the inside of temp sensor in thermostat housing. Tunning in for next video very courios how bad the head is warped from overheating.?

[@sprocket9200]

Indeed young grasshopper, become the engine

[@rbotton6272]

amc jeep 4.0 is a go job if maintained properly

[@toejam503]

I'm surprised you didn't use a "speed handle" to remove the rocker stud nuts.

[@dadalebreton184]

While your there, "IF" you know the engine have a "COMON" break or failure that is not shown or broken "YET", i suggest you change it while you there. Unless its been done prior. I wouldnt change an engine head unless your sure its close or pass the mileage break point usualy knowed to do so. Like if your engine have 100k miles and the part fails at 200k miles, i wouldnt. But if your at 170-220k miles and your doing a complete restoration, i would definatly have it changed or inspected at a shop. Maybe just the fact you rebuilt it release the stress on the parts that are prone to fail. Have them check to a pro shop. Don't assume or guess! Be safe. Nice content by the way. Thanks Uncle Tony. I learn every time or remind me of things i forgot form not doing a certain restoration for years.

[@dh2360]

Just like the old Tv shows, it stops on a cliff hanger...... still waiting on the UTG metal lunch box or UTG action figure to hit the stores.

[@jfjude891]

Uncle Tony, Thank you for having the ba!!s to talk about "communing." This is a good way of letting some the art shine on. Jim from New Dorp

[@debluetailfly]

Zen and the Art of Engine Rebuilding. adapted from the old book Zen and the Art of Motorcycle Maintenance.

[@waynebuzzell2483]

The way of the gear head monk.

[@tabbott429]

2000/2001 heads (0331) are prone to cracking but even the "good head" before those years will crack if its overheated.

[@joshh454]

Agree on the hand tools. Liked this style video a lot.

[@jeffsr8300]

I whole heartedly agree no power tools for disassembly, mostly breaker bars and speed wrench.👍👍🇺🇸🇺🇸

[@darrynworthy7129]

that first bolt with gummy stuff, on the jeep engines that is a bolt that accesses the coolant, i believe its the only one, so you have to put a sealant in the thread

[@salledrab283]

I am liking this series

[@peacemaker6156]

I just pulled the heads off my 318. One pushrod was diffrent it had round ends. Same size as the others just diffrent ends. Why ? It ran like a top.

[@joehoeing6590]

Do you zero the cam at the top of #1 piston's compression stroke or exhaust stroke?

[@williammccarthy5696]

The head bolt with sticky stuff has had thread sealer put on it as it goes into the water jacket. 4.0 head bolts can be reused once . If the head has been off previously you are supposed to mark the head bolts with white paint to signify the bolts have been used once .

[@Lecherous_Rex]

Where Tony says it will push the screwdriver down at tdc, that's for stuff with the plugs on the side of the head. My twin cam 4 banger, being an overhead cam motor will push the screwdriver up vertically. Had to verify my damper ring timing when setting up megasquirt aftermarket ecu, under boost ignition timing is critical. First time I broke out grandpa's timing lights, legit just adjusted the tune with the up and down arrows on the laptop to accommodate what the light showed.

[@UncleTonysGarage]

Good point!

[@z33tanner]

Do you unbolt all cylinder heads from the center? I have always gone in reverse of torturing sequence so from outside in. Loving the series so far even as a heavy line tech, great tips.

[@brianbrigg57]

If I'm stripping an engine I like to have a set of thread chasers to clean out any threaded holes. A wire brush will work on the bolts but I like to make sure the threads are clean in those holes. It doesn't take long but it makes reassembly just that bit easier. When I lived near a shop that did electroplating I would even take all the loose nuts and bolts and have them hot tanked and plated. Only cost a few bucks back in the day but it looked nice when the block had fresh paint.

[@MapesTom]

Don't throw away your torque to yield bolts. Save some and use a grinder to cut slots in the threads long-ways, and make yourself a thread chase for later.

[@pauljones2031]

That noise is your stolen watch. We Canadians are very crafty...

[@jeffreyrubish347]

If the 4.0 head is a "Tupy" you're okay. You can see that designation on an intact motor looking inside on the head under the oil filler cap.

[@ChrisTheBmxGuy]

Typically if im tearing down and hear a noise like that ill take the valvetrain off and repeat to see if the noise is still there. I use an electric ratchet on most things and have learned the "feel" with that and you can still tell if something isn't right. Head bolts i loosen by hand then zip them out with my 3/8 electric impact. This is coming from someone who is a dealer tech though.. if inexperienced id highly recommend doing everything by hand to really get the feel of it. Also you never forget that burnt smell. I can tell someone is doing a teardown on a overheated engine from across the shop. Smells like money, pain and misery lol. That one head bolt probably had thread sealant on it.

[@TheMajictech]

If you want compression you gotta change that crank and rods to the ones from a 258, ask super Dave. . . . I mean Mr Vizard about those stroker motors :)

[@sirjhonson8218]

Back in the 1990`s I did a rebuild on a 300 inline 6 that should have of cost about $1,500 to $2,000 but I spent $4,900 on it , and only got about 30 hp extra . I screwed the pooch on that one . LOL All the parts were working against each other . I slapped together everything thing that I read about to make power and it made no power . Man did it have low end torque but the top end played out quick .