Jeep Overheating! Bolts didn't make it back in! Jeep Grand Cherokee 4.0

This Jeep Grand Cherokee Laredo with the 4.0l straight six engine came in. The driver said it needed a water pump and the thermostat had already been replaced. During the inspection we found that thermostat housing was leaking antifreeze all over the serpentine belt and the water pump and cooling fan was blowing engine coolant all over the engine compartment. Further inspection revealed that the thermostat housing bold was threaded between the thermostat housing and a metal heater core bypass hose that screws into the water pump. We removed the thermostat and housing and found orange RTV silicone sealant covering the thermostat gasket. The bench grinder with a wire wheel was used to restore the sealing surface of the thermostat housing and the thermostat was reinstalled with the radiator hoses and heater core hoses. During the test drive, the engine seemed to misfire and backfire. There is no check engine warning light on the dash.
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”Intro Music by Karl Casey @ White Bat Audio”
Thanks to Jesse for making the intro and graphic for us to enjoy!!!

[@aciddiver1978]

This is a "I KNOW SOMEONE WHO CAN DO IT CHEAPER" moment😊

[@Racingnut24]

Yeah amazing...I'm of the opinion that something this critical. Let a reputable shop do it. Chances are they will give some sort of guarantee/warranty so if they botch it it's on THEM but you do it cheaper and botch it it's on YOU. Spend a few extra bucks get it done right

[@turboturtle9083]

@Jed1421 and then it started leaking and over heating so a professional with insurance was the last to work on it in case he cooked it.

[@moviesandfilms4you]

Hey!! Cletus done the best he could after and for a case o beer!

[@bobbg9041]

The jeep dealerships so overworked replacing parts that are not bad, they rushed the job only to tell him his water pump was also bad! But also the case of beer concept works, in many cases its the same quality of work. Most the guys at the dealership got sick of the games and opened there own shops like Raymond has.

[@jeffro221]

@@bobbg9041 "........ replacing parts that are not bad,...." Awesome. Classic stealership move!

[@scottwilliams1976]

Im thinking the person that replaced the thermostat thought they screwed the bottom bolt home but missed the hole and tightened it the way you found it 😂😂

[@pebosk]

Exactly my thought....

[@ray01012010]

1000 agreed and def wasn't a true mechanic because they would've realized it wasn't tight as well as the top one

[@ray01012010]

Definite diy attempt fail

[@DaveZeichner]

Exactly

[@Blynncliff]

Kinda makes me feel sorry for his wife.

[@user-dc4tx3qr5d]

My friends dad was a mechanic. One time a guy who didn’t speak English was showing him that the horn didn’t work. Glen opened the hood. The wire came off the horn. He put it back on. The guy tried to give him money. Glen laughed and said no. He was such a good influence on me. A good honest man like Ray. Glen’s wife was such a sweet woman. Like the wife unit. They both helped me a lot. From the age of 13.

[@Racingnut24]

4.0 straight 6...good engine. Lucky for this owner they're hard to kill

[@johnquinn4680]

Bro I shit you not I ran a straight 6 with 220,000 miles on it for like 6 months with no oil until it finally blew on the freeway one day. Those little motors are fucking bullet proof.

[@gus9225]

I'm a rural mail carrier and my 4.0 has over 500,000 miles on it. :)

[@Paramount531]

Because it was designed by AMC, not Chrysler.

[@bob733333]

Some of the early ones have a bad head. But they are not terrible to replace.

[@jeffro221]

@@johnquinn4680Imagine how long it would go with oil! :)

[@mike.47]

Dare I suggest that the owner found the limits of his automotive expertise and botched it all?

[@Dennys854]

Once replaced my spark plugs in my 76 Mustang II and it ran horribly missing. Not knowing what was wrong took it to my mechanic Mario (Italian). An hour later he called back to get the car. I showed up and he's smiling at me. "Who muck upa da plugs?" "huh?" "WHO MUCK UPA DA PLUGS? She'sa cross treaded in number 6" He dropped a helicoil in and checked the rest, but his response to me always stuck with me.

[@marklivingston330]

I concur.....sir.

[@jacobharryman822]

RTV on the cooling system always indicates somebody didn't know what they were doing. (I totally have done that before 😭)

[@horacecomegna335]

I’ve learned that most men think they are auto mechanics, body and fender repairman, and lawyers! 😂😂😂

[@startrek133]

I wish more people were like Ray .. you can tell he truly cares about doing things the right way ...

[@SheltonBinkley]

Man, sometimes when you're drunk enough, you might get the wrong hole, or no hole at all, and never even know the difference.

[@charleshoops2307]

funny

[@MacRODesign55]

We can all pretend you were talking about the blind threaded holes for the thermostat housing, right guys?

[@bobbg9041]

If only the motor could say wahoo Id say he missed the hole by a ____ hair.

[@terrywebb8636]

Some mechanics would have up sold, the owner a water pump and only fixed the real problem. Thank you Ray for your honesty and for taking us along, great video sir.

[@MitchJ]

I just subscribed to your channel because at the end of the video I just watched you said- "If you don't like this video or if you don't like me... I don't care. I don't like you either." Awesome. THAT'S the kind of guy I will subscribe to! 👍

[@richardstone5241]

The 4.0 Inline Six was one of the BEST engines ever made! A shop I worked at near MOAB Utah used to upgrade these engines with performance parts. These engines like to have their oil changed on a regular basis (every 3,000 miles) regardless of the type (regular or synthetic) and their coolant changed more frequently (every two years). Other than that they are fantastic engines (almost bullet proof)!

[@stevemccooleq]

And don't use the 0W-20 oil that you put in these newer cars. This motor is old school, it wants real (thicker) oil.

[@richardstone5241]

@@stevemccooleq Yep! We used a 10-30 in the winter and a 15-40 or 20-50 in the summer (desert).

[@brianjrichman]

Ray, I see you are using a "Jeepers Creeper" on a Jeep! It's Friday!!! 🤣🤣

[@patrickgoodwin3085]

Very enjoyable! Hopefully the owner will allow the addressing of the backfire. Have a great day!

[@turboturtle9083]

When Ray is playing cleanup man on someone else's work this video is his insurance.

[@ldhare]

FWIW: You might want to consider going down to Lowes, HomeDepot, etc. and buying a couple of black plastic motar boxes to mitigate various wide spread, potential oil, or coolant spills in leu of those small, green plastic pans that you tend to use. Just a thought now:-) PS: they also make for great canine beds after throwing an old blanket or two as a mattress.

[@larryjohns8823]

They make a great cat litter box also.

[@RadioReprised]

If you start the bottom bolt by fingers then jam the socket against the belt with the free hand it will deflect enough to let you tighten it....I was in there four times in one day testing thermostats so I figured out what worked.

[@clintprice2123]

Nice, you saved him from needlessly buying a new water pump!

[@johnquinn4680]

The total of labor is still probably more than the blue book value of the whole vehicle. The customer is OBVIOUSLY an absolute imbecile.

[@k9under]

Love them 4 liter inline 6 engines.

[@Rocket39Smoke14]

Love working on the 4.0L. Best engine ever!

[@patrickchavez3848]

You know, I was considering buying a jeep. I've always liked them and now they are coming out of the factory with lifts and nice wheels, trying to entice me but after seeing the litany of problems Jeeps are prone to I have changed my mind and I'm sticking to my preferred makes and models...great video, thank you Mr. Ray. Have a great day and an even better tomorrow...

[@mattbrown5511]

The AMC/Chrysler 4.0L inline 6 is an excellent engine. But like all vehicles, they are only as good as the maintenance that the owner does. Now, the Pentastar/Fiat engine and transmissions are pretty much junk.

[@andysinn8655]

The 4.0 is a great motor but have a bit of chatter on top end and high fuel consumption.The 318 in older jeeps are also good motors but suffer from high fuel consumption.@@mattbrown5511

[@dogsense3773]

My 2014 needs a head gasket at 72,000 miles!

[@mattbrown5511]

My '06 has had 2 clutches put in and it swell over 150K miles. I also had the timing chain done at 100K just ease of my mind. And the clutches were my fault for training my daughter to drive manual in it.@@dogsense3773

[@Vondoodle]

Love the proper clock on the top of the dash

[@scotthassett2676]

thanks for the better shop music.

[@jiminma50]

Oh thank you for brining Lauren in for her mandatory appearance. LOL She is such a sweetheart brining you coffee and lunch. I was always told never to work with family....it never ends well. But you guys seem to work amazingly together! You guys are both amazing!

[@bobbg9041]

30:45 I love the crash sound closing the drivers door, that tells me someone busted out the drivers door window it got replaced but the shop that put a new window in didn't vacum out all the glass shards. So when you slam the door shut you hear a crash sound.

[@billdeibner7105]

I was glad you cleaned up those bolts, I was twitching a little before you did. 🙂

[@DavidGesswin]

That Heep gave a whole new meaning to Shade Tree Mechanic .

[@bearpuf]

Thanks for the video of this repair Ray. Your description of what was causing it and your careful repair process are an education in itself. To the owner I would label this event as 'Gross Negligence' and suspend his use of the vehicle until he gets everything else with the Jeep repaired (backfire, ABS and whatever else turns up).

[@proudcanadian5713]

This is one of those moments where either the owner or his friend said, "It's only a thermostat, I can do that easily." MOST times they're right but they also have a chance at screwing it up. This time they lost and you saved their butt, Ray. Well done.

[@johnthompson1453]

With thermostat housings I use my belt sander or some sandpaper on a flat surface. I have seen some housings bowed quite badly.

[@eugenealbrycht2132]

How much is a new housing? I would go with, since you’re in there.

[@zenarcade6551]

Troy's spider senses are tingling...🤣

[@Grayhook1]

Had work done at The Blind Mechanic down the road. Jeep specific creeper… my aren’t we moving up in the world!😄 Sanding discs on an angle grinder make much cleaner cuts (ask me how I know).

[@sargemarine3709]

Got over 650k on my 92 Laredo. Never cracked a valve cover. But the I am a preventative maintenance guru.

[@RB-pc7tg]

I love those 4.0 engines. Strong, reliable, easy to work on, all steel long block, timing chain (not belt)

[@tomhendricksen1805]

My working carrier has many years of repairing electronics. Mostly car radios and communications equipment. In my experience I learned that the customer rarely actually knew what the issue with their item was. Some even argued when the item repair was completed and returned to them. I have noticed the same thing in some of the videos you have put on your channel. I appreciate seeing a mechanic who understands what needs to be done and does the repair in a responsible and complete manner. I wish all were the same, but sadly that is not the case and you all get the bad rap because of it.

[@joemuncie9187]

Great video Ray, as usual. That backfiring is strange. Those usually last 200K without any serious problems. Several of my friends own Jeeps with that engine and we've only had to change water pumps, thermostats, and power steering pumps. One of my friends has an old CJ with the 4 cyl.

[@RJARRRPCGP]

OTOH, it seems to happen more on the 3.7 V6s! The 3.7 V6, which was usually only used in the Liberty, were used in 2006-2009 (or 2006-2010?) Grand Cherokees. They were also used in Durangos right after the 3.9 V6 and 318 V8 got discontinued. (after 2001, most likely) If you have the 3.7, prepare to get another ECU. :(

[@methanial73]

If I'm not mistaken those bolts go into the water jacket! You should have put gasket sealant on them.

[@ohiowrencher8650]

Is the check engine light blown out? No flashing CEL... Also why are you suspecting valves before plugs and wires are looked at? As you know it can also be a fuel delivery issue... weak pump, fuel injectors, etc...

[@jdesaavedra0432]

I gotta have one of the kiddie toy coolant funnel sets.

[@litz13]

I've pretty much gotten to the point with my 97 XJ that when it comes time for a cooling system service, I just replace it all in one go. Parts are so cheap, and you have to take it all apart anyway, why not?

[@bobby9195]

Good morning Mr Ray, Happy Friday sir, hope y'all have a wonderful day and weekend. Just wanted to thank you for all your videos, I have used a lot of them to help me fix these old cars lol

[@jimdavis6833]

Green tea, yech. I tried that krap way back when I was stationed in Okinawa. Never got to liking it. I did learn to eat with chop sticks though.

[@gwharton68]

That funnel arrangement for the radiator is very neat. Great video as always.

[@user-lq6yo8tp5g]

Thank you for taking the time to wire brush the thermostat housing. It looked knarly.....I would feel better if your bench grinder was bolted down.

[@johnt.848]

And used two hands.

[@alanwelch6594]

Considering the skill of the previous mechanic, it is amazing that the engine is still running and capable of back firing.

[@OGYettie]

I'd put money on that someone put that screw there thinking they had it in the screw hole.

[@pedroarroyo9684]

I said the same thing

[@ralph5476]

Agree totally. I think Ray was just being nice, and not saying the obvious. Bucketing the owner or a mate of the owner may not be good for future business.

[@john_thorpe]

I was thinking the same since he used the powered ratchet and it came out like a bolt would from a bolt hole but didn't when he tried to pry it out.

[@Michael-yi4mc]

If I was a mechanic at Ray’s shop, I would be dancing to the music all day long 🎵

[@keithmalmberg8395]

Had a 2000 Cherokee. It developed that miss fire. It had 3 injectors that were just trashed. They would not close at all. It had just under 200k. A set of rebuilt injectors and off it went for an additional 50k when Idols it to move across the country.

[@ralfie8801]

Check the plug wires Ray. They very well could be the originals and are deteriorated and saturated with anti-freeze which could make them arc to any metal they are routed close to. That condition could also be exacerbated by the spark plug gap being too wide.

[@francodeiuliis1562]

Nice work 👍👍

[@bentonheath7838]

Leaking valves? Yes with a p 300 code. As you know this head has inserts for the valves. I replaced my head with a improved head (heavier) that corrected a cracking problem in stock heads. Dealer wanted to rebuild the head. NOPE! No more problems and was cheaper.

[@johncadwallader8671]

Nice to hear Led Zeppelin on the play list for a change !

[@johnhpalmer6098]

That's Led Zeppelin, just FYI

[@bullbutter9699]

shhh

[@gn4720]

@@johnhpalmer6098 Auto correct strikes again.

[@572Btriode]

@@johnhpalmer6098 Make a stairway and get the stores open.

[@alien5610]

Scorpions as well! Awesome playlist!

[@randybeard6040]

The 4.0 Liter Engine supposedly was one of Best engines ever put into Jeeps, I have never heard anything bad about them...

[@DKbananas]

They managed to screw it up with the 05-06 wrangler self destructing oil pump drives

[@russelltaylerson4468]

I love a straight six engine! A symphony of smooth. Owned a Grand Cherokee and despite the intermittent cutting out it was a sweet engine

[@LilYeshua]

I used to use yellow permatex just to tack in the thermostat just to hold it in position

[@ronv6637]

Ray stuff a rag/papertowels into opening before clean up to keep contamination out of head. How about system flush before thermostat install,if head looks that bad, radiator/ heater core probably bad too. Don't you have a cooling system pressure tester? To test for head gasket have a combustion gas tester?

[@wayneessar7489]

Maybe the client did not approve that extra expense...

[@ronv6637]

@@wayneessar7489If thermostat/waterpump cost was ok a few dollars more than the gasket was still well below authorization and good insurance with that level of corrosion/possible system blockage

[@AJwoodway]

Saw Wife Units twin at the gym in Waco this am. They say everyone has a twin. This is a weird planet… I think i’ll stay longer. 😆

[@wayneessar7489]

Is that Waco in Texas? I saw that name on drainage products here in Canada. ...also is that where the Kool-aid guy was from?

[@AJwoodway]

⁠@@wayneessar7489 Central Texas. Kool aid guy was jim jones from Indiana. He brainwashed a bunch of people and took them to Guyana and killed them. You may be thinking of david koresh. He brainwashed a bunch of people so he and his sick cronies could abuse 10 year old girls. It was way out on the plain not Waco but we’re the closest city.

[@CraigGrant-sh3in]

I would guess that whoever attempted to do one of the easiest fixes thought they blindly had the bolt in the hole and screwed it between the housing and hose. It probably bottomed out and they thought it was tight though tight didn't seem to matter on the other bolt

[@vandalsr1959]

You have soooo much patience with flashlights they would be on the other side of the shop if that were me

[@SiblingCreature]

Welcome to a new episode of Just Rolled In... Oh Wait... Wrong channel! 🤣

[@desotosky1372]

I think this may be an example of why you start bolts by hand first. Suspect that lower bolt was run in under power with no sensory feedback it was misaligned. Thanks for the video.

[@jamesnall569]

At 8:45, the song Welcome To The Jungle is a good song for the quality of work by the owner.😅

[@LiberalsAreTheDevil]

jeeps are notorious for head gasket leaks. Everyone I know that has one has had that problem eventually!

[@michaelray5595]

There was coolant on the fan shroud. 🤣🤣😂😂🤣 ok, ok... it was just a drop, but it was there. 😂😂

[@Casspederson]

I have and love an 02 wj Laredo, so this video hits close to home. You’re the best Ray! 🖤

[@maxxmich]

never loosen those plastic petcock . if it breaks ur screwed... just use the lower hose....

[@michaelray5595]

"DING" Fries are done! 😂😂😂 everytime!

[@kevincurry4735]

Afternoon Ray I say it’s a Jeep thing but can’t blame the Jeep on this one.

[@LesReeves]

You should buy a bore a scope like the one that Ivan has at PHAD it has lens on the side which gives an almost 360 degree view & it was really cheap & extremely clear.

[@dalejones3862]

Ray doing a great job as always

[@chevtruck1000]

Fun fact. A little bit of chamfer put on the bolt holes of the machined surface side of the thermostat housing gives room for an O ring which will hold the bolts in place for reassembly.

[@Tony-Tequalla]

Car Wars. Return of The Wife Unit. 😏👍

[@schsch2390]

Reminds me of my '85 Cherokee abortion. Hydraulic clutch multiple problems but the crowning achievement of the dealer was replacing the water pump leaker with a reman that had the impeller on backwards. Overheated about 2 miles down the road, drove back to the dealer who took 5 days to figure out the problem. No further charge and got a free car wash out of it.

[@shaunkelly9053]

That idler pulley looks like it’s seen better days too.

[@davidmoore_oo1]

Ray, check the engine ground/dipstick mount stud . . It can be loose/corroded and cause a very difficult to diagnose misfire only under load. Also check that theres not a vacuum leak where the intake/exhaust bolt to the head, because thats a 4.o thing. Also, I'd bet the driver side engine mount is broken. It's a Jeep thing.

[@stanbrown5425]

12:43 "my sweet satan" in reverse...😂

[@scannerlanier471]

There's still time to change the road you're on..........

[@bigj200016]

Always nice to see professional mechanics using Harbor Freight stuff.

[@Gizmetti]

Are you implying something is wrong with Harbor Freight quality?

[@bigj200016]

@@Gizmetti not at all.

[@stevenclaeys6252]

Thank you for another great video. Stay safe out there. Cheers

[@tophersupreme5573]

That jeep is supposed to have an electric cooling fan, not mechanical.

[@throttlebottle5906]

"hold my empty case of beer, so I change this here thermostats" while drinking the second case...

[@vc8939]

Good Friday to you Ray, Stairway to heaven does not make up for a Dave sighting. So, next video I will be looking for a Dave sighting to make up for this video. LOL! I was surprised that the jeep still had coolant in the system with that ‘poor’ installation of the thermostat housing. As usual, love the videos and best to the wife unit, with whatever was in that cup!! 😂😂😂

[@terrymax5340]

My neighbors GMC truck had an overwhelming problem. He had it in the shop . They did not know why it's overwhelming. I found a plugged up radiator . I replaced it . Fixed .

[@Gideon_Judges6]

Well, that's actually underwhelming.

[@mikeyd5969]

Sometimes I can just cuss at auto correct

[@fleece192]

Great video Ray. I like that funnel thingy

[@msgtb]

Whoever replaced the thermostat put the top bolt in and the bottom bolt was out of his sight. He misplaced the bolt under the thermostat housing not in the correct hole then ratcheted it in. That's my take on what happened.

[@michaelsnively3621]

One bolt and the rtv for the win!

[@bobbysenterprises3220]

You should be able to change ign timing on these. You use scan tool to set to 0deg and you move the cam sensor off what used to be a distributer to match the scan tool zero. Essentially making sure the cam sensor in the distributer housing (not a full distributer) to the crank sensor. This sets the baseline for the computer to rin the coil pack timing

[@kennethnichols7263]

Why don’t you use a coolant system tester? You can pump the system up and see if it holds pressure

[@jhorton1600]

Red, blue or black schmooze (in very small amounts) is useful to keep the gasket in place while getting the bolts started. Soft hose, chewed up belt, change them before they leave you walking. I feel that battery may have a parasitic draw because it seemed to start fine after the alternator ran for just a little bit. But I'm just a parts changer, not a mechanic.

[@michaelstoliker971]

That smoke woud be called a ghost on those ghost hunting channels.

[@bulldogshouse9970]

I like the operation you did on this when you did a great job keep up the great work 💪💪

[@Thonofthatan]

Have you ever tried using a vacuum assist coolant refiller? It's easy to know if it leaks if it doesn't hold a vacuum. Then you waste less time and coolant. It may not be apt for this application, but I've never seen you use one.

[@ALConfederate]

Big fan of the 4.0. Had a '98 ZJ with that engine and it took all the abuse I could throw at it. Sold it in a fit of weakness when I saw something I thought I'd like better. Heh. Guess what? :) Still, I'll get another one soon.

[@jpcallan97225]

Thermostat problem not noticed - air bleed hole missing. The Jeep Service Manual (I have the 1996 edition, see pages 7-32 & 7-33.) states there should be a 1/16" to 3/32" air bleed hole in the flange of the thermostat on the 4.0L I6 and this hole should be at the top, 12 o'clock, position. A factory part was the hole, but aftermarket thermostats never do, so it must be drilled. If this isn't done, air is trapped in the head causing hot spots until the tstat opens.

[@user-qg1ov2qf6f]

Good Morning Ray, Make yourself a hose to connect to the drain on the radiator long enough to reach into the drain pan.

[@danwesten2771]

I always say to customers who suggest to me what to do that, "If you knew what you were doing, I would not be here!"

[@michaelp.Watermaker]

“Stairway to Heaven” 😌

[@rockchalkjayhawk0]

Could’ve used this video a couple days ago, just did all that to my 03 4.0

[@Theoldchum]

I think a cylinder is intermittently losing spark to ground causing the backfire. A bad valve usually causes a more consistent backfire. Hopefully we'll get to see!!

[@robertmcbee4671]

Buzzing your hand while using a sanding wheel... I hate it when that happens! The amazing part is that nobody had to tell you to move your hand!

[@peterwong9458]

When I heard “Stairway to Heaven” playing, I thought the Jeep was on its way to jeep heaven.

[@andreichichak5242]

Buddy says that we need to see something in his Jeep, NOW. We run down to the parking lot to see the clock on the dash change from 10:58, 10:59, 10:60, 11:00. Quality stuff, the same truck would warp the front rotors on long highway drives. The dealership couldn't find any problems and would throw a set of disks at it, free! Then I did some internet searches and found that this is a common problem with seized calipers that would drag on the disks and overheat them. The dealership was pretty grumpy. If buddy had waited just 3 more months, he would have had to pay for a set of calipers and disks instead of it being under warranty. It's a Jeep thing.

[@flipphonewizard5448]

That bolt is one for "Customer States" Ray. I'm sure it would make it on youtube for a good laugh.