Engine Overheats after Full Rebuild, but Why? (YOU WONT BELIEVE IT)

[@AdeptApe]

Thanks for watching. Cooling systems should always be vacuumed filled to prevent air bubbles in critical areas using something like this Airlift on this Amazon Affiliate link: Airlift Cooling System Vacuum Filling System: amzn.to/3D9AlPu @AdeptApe on Venmo or [e-mail] on PayPal for donations, thank you so much for supporting the channel!

[@ianloy1854]

The cooling systems have a design "requirement", it is actually an installation specification that is checked during a installation review, that the cooling system can fill fully using a steady stream of coolant. I can't remember the actual flow rate - but a softly flowing hose is a reasonable description. Sometimes this is made possible through the (discouraged) use of bleed valves at the high point of the coolant lines. OEMs use a vacuum filing system at production so the system can be filled faster and there is ABSOLUTELY nothing wrong with using one. But if it is required to get a full fill it is probably indicating that there is a problem with the coolant lines routing that has been changed or is restricted etc.

[@Rocksteady176]

I bought and used this airlift system 3 times already. It works great.

[@jpbnr2931]

Can't blame the cat for catching a mouse 🙈😂

[@mauricemotors8207]

Good one 🤣🤣🤣🤣

[@woodmanhugh]

Ha !

[@RustyorBroken]

You sir, win the internet for today.

[@davebullock3517]

🤦‍♂️

[@VladGoro25]

Laughing soo hard :))))

[@02dirtymax]

This is why as a mechanic as soon as you think you have seen it all, something comes along and proves you wrong!!

[@bradfordprice3781]

Murphy's Law: what can go wrong will go wrong, even if you don't know it can. The mouse has proven why it is impossible to idiot proof anything. There is ALWAYS an idiot standing by to show how ingenious idiots can be.

[@michaelmartinez1345]

Very interesting find!!! That poor mouse went to the wrong place to sleep... It is a reason WHY I like to put a shop rag or a piece of plastic sheet in front of inlets and hold them in place with rubber bands.... Yes, it does take some time to do this, but it also prevents several hours of troubleshooting and down time, of an extremely expensive asset.... This could easily offset the few minutes of prevention to avert a potential catastrophic failure... Protect open spigots and hoses before moving onto the next steps of repairs....

[@uncle_moose]

And then there is o'tools law that states that Murphy was an optimist.

[@pickelsvonbrine]

I have never even heard of something like this! Wild.

[@stuartandrews4344]

@@pickelsvonbrine First time for everything...

[@upstatehauling6996]

Thanks Josh, I should have brought it to you to begin with!

[@AdeptApe]

Always happy to work on a Cat or a mouse in this case. Hope she runs great once it's back together. Thanks for bringing it in.

[@joshuajesch7154]

Love your vast knowledge. Just curious if anything else had to be done to the ole B model and if the waterpump was ok with the rust in it? I have a 3406B 4MG model that I installed a new water pump on...but also has slight rust from a separare problem.

[@diesellivesmatter]

Cats are, after all, good at catching mice.

[@james94582]

At least it wasn't a complete failure on the rebuilding shop.... But glad it is being taken care of now and getting you back on the road!!

[@francomtz7115]

The cat and the mouse like Jerry he always got the cat.

[@WilliamLaakkonen]

Wow- drives home the need to plug orifices with at least a shop towel when things remain open during repairs. Never hear of one of those getting in a cooling system before! Thanks for sharing Josh, love your videos.

[@volvo09]

I saw someone's picture of a cooling system filled with corn.... They left the radiator out for a few days and a chipmunk or red squirrel filled it up.

[@RustyorBroken]

I left the air cleaner off the intake of a diesel for an extended period of time once. After putting it back together and firing it up it had an occasional miss and stuff was shooting out of the stack. Turns out that squirrels or chipmunks had stored walnuts in the intake.

[@carlcarlamos9055]

We had a shop rebuilt engine sent out to a job with a rodent nest in it.

[@colincostine9775]

I once left an engine with the manifolds off in the shop during a rebuild in the winter for just two days. When I went to rotate the engine manually after finishing assembly, it wouldn't turn a full revolution. I ended up cleaning out a cupful of mouse bait.

[@Mike_Hughes]

I always try and make sure that my orifices are as plugged as possible...

[@jeriwollmann7366]

Thanks for the shout out Josh. Jerry caused this destruction. Tom finally had his revenge. Made me laugh. Great diagnosis video.

[@AdeptApe]

Thanks Jeri

[@Steve.Vaught]

Lol, the guy who sent the pictures?

[@danielrepman5606]

Very interesting! Further reinforcement for capping open ports. We had a Cat come in with a mysterious overheat issue that turned out to be a blue shop towel in the oil cooler, coolent inlet...so along with plugging ports, make sure you remove everything...lol.

[@GoldVP...]

Same with my cat in the Pete. Except it was a rag from a new pump install. I pulled it all apart on the highway, halfway between Edmonton and Grande Prairie Alberta, and thank goodness I had 12 bottles of coolant

[@badgerpa9]

Cat caught the mouse. Guess he wanted to leave this cruel world, just chose a bad way to do it. Either that or he liked his alcohol and had to much Ethyl. Good education on keeping openings covered and plugged when working on engines. Glad you did a video on it. Be safe Sir.

[@edwarddavis507]

Great lesson for anyone who does engine tear downs and rebuilds. Thank You for sharing! So glad I caught this video!

[@75LS1Vega]

This is the second time I have seen this exact problem. The last time I seen it was on a 1958 Ferrari that had been apart for a while. Apparently the mouse made a home in the radiator while it was in storage. When the customer reinstalled the radiator, the mouses home and his/her siblings/children met their demise at some point and clogged up parts of the cooling system!! One of the odder diagnosis I have been involved in during my years as a tech!

[@ericdziadosz7145]

Wow, that's weird but makes sense. Worst animal versus engine one I heard to this point was a landfill compactor (Al-Jon), had a Cat C15/D398TA pre-DPF engine (its been 20+ years since it happened), and it had been parked overnight outside of the maintenance shop at the landfill after running the previous day. Early morning, Operator comes in and fires it up only to be startled by the immense amount of racket that occurred when it cranked over and fired up. Shut it down quick, but the damage was done. What happened? Somehow a stray cat (no pun intended) had crawled past the shields over the engine cooling fan/shroud, and met Mr. 600 HP Caterpillar radiator fan, and it had dismembered the feline and shattered the blades on the 6 foot diameter nylon fan blades. The blade remnants ended up piercing the radiator, and I felt sorry for the techs from our shop who had to go out to it, as they were picking out pieces of the furry culprit from the engine compartment for hours. Radiator, fan, reversing hub, and some of the shields had to be replaced. Reps from Al-Jon came out as they had thought they had it closed off well enough that Mr. Whiskers could not gain access to the void between the fan and radiator during shutdown. They came out and went over it and made improvements to the engine compartment so that it would not happen again. Ironically it was the only time that an animal had ever gained access to a space like that, even on the older Detroit 8v92 powered compactor machines that weren't as well protected as that new machine was. Needless to say, it was the most expensive Cat fight I had heard of up to that point.

[@francomtz7115]

The problem with new machines is they are too tight for anything and if a critter gets in there they can't get out in time when they sense the operator.

[@rcnelson]

I once helped lift a huge Cat radiator still in a heavy wooden crate. It's hard to believe a fan blade for something that massive could be destroyed by an 7 lb. cat.

[@konradcomrade4845]

I put a cloth, sprayed with some insect spray under the motor hud. Animals don't like the smell and stay out, even when they would be attracted by the remaining warmth of the engine in night!

[@CharlieK92004]

Aw, poor Fievel.

[@lbz4life534]

I work for a large city municipality. we have a fleet of trash trucks. We have never found a mouse in side an engine but we have found them everywhere else. Mice and rats both in the trash bodies usually where the hyd leak is, that's right they chew through 5000 psi hyd hose.

[@juniormoraes5195]

Hi Josh I am a diesel engine mechanic here in Brazil. I always follow your videos, here we don't have Caterpillar in trucks, but we have in machines and industrial. Your explanations are very nice. Success to you.

[@ilovemydad1416]

For AL G.RITHIM cuz I don't have much to say, but darn, you and ezrider,are my favorite diesel mechanics. Although he is more a driver than mech, his knowledge is amazing.

[@aaronk534]

Thats crazy. I think about that occassionally with an open engine especially outside. Great vid

[@RustyorBroken]

It's always a good idea to use a little Decon additive in your coolant.

[@jimgam730]

🤣😂

[@robertthornton7553]

Thanks for a great video.i once had mouse in my heating boiler,But never in an engine yet ,can I suggest someone needs to change the cat 😺

[@johnmarshall4442]

I work in Aviation A&P for 26 years . Good video in aviation you always cap and plug everything when you take things apart. GOOD REASON WHY .

[@JesusTorres-qr1gz]

That's very kind of you to share it with us, most kind, from the endless summer paradise Puerto Rico, Jesús Torres.

[@FarmerSteveO]

I saw something happen similar once on a 3306 TA in a D6D CAT on an in frame rebuild where a shop rag was waded up and left in the port between the aftercooler and head. Took a while to figure out, but just have to go through the troubleshooting process like you did! I guess kind of like a doctor forgetting his tools when he sew’s up the patient! Lol! Great video!

[@XFolf]

I feel very justified suddenly for always being OCD about blocking up every line/hose when I'm working on stuff, tho in my case it was just to keep out dust LOL!

[@thisisyourcaptainspeaking2259]

Mice love to build nests using all kinds of stuff that clogs passages. Some areas, bees do this as well.

[@mattdeckert6150]

And mud daubers..

[@bencojo6846]

And that folks is why you keep things covered up till it’s time to install them. Always love what you are doing, and have learned a lot from you, like how to run overhead and how to remember the sequence

[@robertficek7586]

RIP Fievel!, he was well known to make nests in the engine compartment, but a baller move to try to move inside the block.

[@VepaAus]

CAT and Mouse , how ironic. Kinda like Tom and Jerry situation. Great pick-up mate.

[@johnmumford1135]

My dad has that same problem almost with the C15 in his truck. In 2021, the temperatures were rather high at about 210°. Then one night in Kingman he saw a small coolant leak but said it wasn't that bad and wouldn't do anything, the very next day, that same leak put us on the side of the road for 7 hours in the middle of nowhere, about 10-15 miles from Flagstaff if I remember correctly. Later that year, they had to put a new radiator in it I think for I don't remember the reason but it was all rusted out below from when they switched the coolant from the green stuff to the new red stuff. A few months ago, the engine was rebuilt and he said it still runs at about the same temperatures as it did before. But he said it still gets hot and he doesn't know why, he thinks it's a low flow water pump. I wish his company would send the truck up to your shop to take a look because their mechanics are just interns right now, then one quit a few days ago so it's just one now.

[@alandominguez3839]

Take it to empire 😉

[@mikebressette6291]

I did an out of frame a few years ago. put the truck back together and started it, very shortly after starting a very black squirl jumped out of the stack and ran out of the shop. it must have got in the exhuast while the truck was outside the shop while the engine was being rebuilt, and was in there when we put the motor in and hooked everything up.

[@B0RN2RACE100]

That is wild. I was having a conversation with my stepdad the other day about how a 3406 can pressurize the radiator but not blow a head gasket, he told me he think the space between the valves doesn’t have enough metal and an overheat situation makes hairline cracks on those heads, he has had to change a few heads already

[@billyhorton5779]

These older mechanical fuel injection pumps (scroll fuel system) people would liked to "turn the fuel up' for more HP, would also result in cracks in the cylinder head and other engine damage.

[@lylejohnston4125]

My daughter inherited a '69 SS el Camino that hadn't run in 23 years. Mice made the exhaust their home and peed on the #5 exhaust valve so much, it stuck open, broke off and took a massive chunk out of the cylinder wall of the 396. The Hooker headers were rusted out and They even made it through too the intake on one plane due to the valve overlap. I plug exhaust during long storage now!

[@yyl3683]

Thought it's the shop guy left a rag there, didn't expect the end result at all😂

[@wazza33racer]

Amazing the engine got as far as it did, without catastrophic failure.

[@ianatkinson8464]

Rats and mice do love the taste of coolant and screen wash. All ways clean any spilt on wires or engine off.

[@jamesford7182]

I used to love getting difficult problems like this. It took the drudgery out of the week. Beats the hell out of doing the same jobs over and over. In the early '70s I think I changed the head gasket on every Chevy Vega every made.

[@bernardkinsky1637]

I had a similar problem with a brand new CAT 245 excavator that was shipped from the USA to SA Capetown .We unloaded the machine from the ship, loaded it on a lowboy,the radiator cap was missing ,while I was were unloading the machine in the yard I noticed that the water temperature was very very high.pulled it in the service bay and after a long while of testing and guessing as to what the proplem could be. We found pieces of a dead bird in the radiator hose .that was in 1978 and have never forgotten about it .

[@GeekBoyMN]

Definitely one of the more bizarre problems I've heard of. Good catch!

[@K_Hansen]

in my years of working on the 3406 PC TA's and A models i have seen two spun impelers one was split the other just spun, probabably from re-using the impeler to many times after a seal change

[@donw3912]

Looks like the Cat ate the mouse... A great video..good teaching one to show the importance of keeping open holes plugged when apart for service...and to look your new parts over thoroughly.

[@screwplanplaybook7121]

I had to replace my water pump engine still getting hot well after the shop, last one in Nephi,Ut and the owner and everyone one was baffled, well oil cooler was plugged, the red and green coolant was mixed anyit plugged up the oil cooler, so pulling over parleys summit was a blast, it over heated going up the pass and when oil cooler was replaced no more over heating issues. Thank you for the video.

[@truckladders4104]

Great video A great example of best practices of covering/capping any hoses tubes open components during rebuild An alternate title dot the video might be A game of Cat and mouse !

[@raymondclark1785]

When I was a parts manager for a foreign car dealership in Princeton I had a mechanic ask for an AMC water pump. We were a dealer for them to. I told him to be sure to read the instructions in the box. He went into a rant about how long he'd been a mechanic A little latter he was back ranting that the pump wasn't pumping Bring me the box! In the box were the instruction, still clean and folded. If you had rad the instructions you would have learned that the new pump has a bigger impeller, you needed to pull a head bolt, install the pump and then use the new bolt that's still in the bottom of the box. Same dealership ran stock car's, one day before a race at Trenton they rebuilt a Chevy V8. When they started it burnt rags were flying everywhere, they suspected they had left rags in the cylinders while the heads were off :( They pulled an all night pulling the heads only to find the side pipes were blowing out rags from under the bench the welder hadn't swept up :(

[@jasonwood9263]

That was a good one. Mice and farm equipment do not mix. Love your work dude and thank you!

[@catslife5501]

Well done Columbo!! Enjoyed this vid👍

[@bindig1]

Oh man. Friggin mice. At first I thought it was a paper shop towel. I bought a 1990 F250 once that had sat for years. Mice made a nice cozy nest in the air filter box and intake hose and made a nice meal of of all the wires under the hood

[@longinogiorda34]

No sh.....?! A mouse????wtf! After 40 plus years of marine engineer work this is unf....in’ believable. Kudos to you 🎉

[@madmax222]

Love these. Happens more than I would care to admit in water cooled systems with open recirculation

[@a68k_de]

You can quickly get into really bad trouble with bad parts. Just like it happened to me. I had the water pump replaced in my 1983 Ford Capri with the 2.3 liter V6 engine. The first one was from SKF and made noises - exchanged - also made noises - exchanged... then another one from Hella was available. I have photo evidence on my website. The housing around the pump wheel was closed and either happened when the pump housing was cast or was not separated afterwards? In any case, the pump wheel could not transport water and the engine became too hot. We puzzled around for ages until we removed the water pump again and compared one pump with the other one... (End of song: We reinstalled the old water pump that I actually wanted to replace when rebuilding the engine, and it still works today). But you can now get such a step sold... it's unbelievable.

[@toolfreak11]

This shows that capping lines and hoses for contamination control is really important. Also, how do you meet flat rates while making videos? The cat dealer I work at skimps is on time pretty bad

[@Horus9339]

Now I have to say I have seen it all, I would have never guessed that in a long time. Thank you for sharing? Really though, thank you Sir.

[@tihspidtherekciltilc5469]

I'm working on 12 snowblowers currently and restoring a 79 Ariens to add to my collection. Out of the 13 machines, some maintained but most not, 9 were damaged by mice with some mice getting caught in sprockets and chains. Not exactly the funnest of jobs having to clean the transmissions out and replace broken chains but the little bastards put food on the table. One ate through a plastic fuel tank and overdosed on ethanol.

[@kraftzion]

The old ethylene glycol coolant was an animal attractant. Many dogs died from drinking it. Maybe the newer stuff still has a sweet taste/smell.

[@ArielJRodriguez]

Awesome diagnoses! Really enjoy these videos, you really know your stuff. Thank you!

[@rogergroover4971]

That’s crazy! Who would ever guess? Very cool breakdown and explanation! Thanks!

[@dereksmith1803]

Wow! Wouldn't believe it if I hadn't seen it. Would love to have seen the customer's face when you showed/told him.

[@fanman4230]

Back in my dim and distant past I had a weird overheating problem arrive at my workshop. It was on a Morris Marina with a 1300 A series engine. In slow moving traffic on a hot day it would run at normal temperature, but, out on the open road it would overheat, basically the opposite of what you would normally expect. After a bit of head scratching I made a discovery that I had to confirm with the customer. I asked if he had recently had an accident repair done, to confirm what I had found. He said yes he had slid into a gatepost on an icy bend and had the car towed to the main dealer for a front end rebuild and new radiator, waterpump and fan. The A series engine is fitted to a lot of different vehicles including the original Mini. I had noticed that the radiator grill was getting hot when it should have been in a stream of cold air. Turns out that the dealership had fitted a Mini fan that in its intended transverse engine vehicle pushes air from the engine bay out through the side mounted radiator into the wheelwell. In this inline engine it was, at speed, trying to force air against the incoming airstream, effectively preventing air from passing through the radiator. When moving slowly this wasn't an issue. I replaced the fan with the correct one and problem solved. We also gained a regular customer.

[@MarzNet256]

That is so crazy. The zoom in at the end sent chills down my spine. It's like...a whole new genre of horror.

[@dijebrothers5994]

Thanks for your time. You are very amazing BOSS

[@AstrologerJoe]

Good job Josh! 🐁

[@williamwade7059]

Happens all the time in Wisconsin when the temperatures drop. Mice love to live inside your air and cabin filters. When I haul Trane components all the the hoses and air intakes are blocked off to stop creatures from building nests in them.

[@ZylonFPV]

That was super interesting! It was a detective job and can’t believe it ended up being a mouse! How did the owner react to it?

[@upstatehauling6996]

Im not thrilled, that's how!

[@MrNastytrucker44]

@@upstatehauling6996 at least the shop that rebuilt it didn't destroy your motor through poor workmanship. I think they should east the cost of this repair for you. When i tear a truck apart i always block every single hole off with rags and tape including the air lines because of the mud wasps we have here in texas.

[@needmoreboost6369]

@@MrNastytrucker44 good practice👍 same here in Australia along with all the rodents and other critters ect I’ve seen rods/valves bent because mud wasps or mice have seen a combustion chamber as a nice home

[@sirtitan3028]

I've had issues with people added stop leak to the cooling system and causing the same issues

[@CarlosDieselElectric]

Great find. We learn something new every day.

[@townsendliving9750]

I knew exactly what that was when I seen you pull it. I have had that same issue on a Dodge truck, left the cap off and the mouse drown in the coolant reservoir. No heater for awhile, was very hard to clean out

[@johngoldsmith6629]

I noticed the impeller bolt is non Cat. Have seen the impeller (metal ones) spin on the shaft, mostly after market water pumps. These water pumps use to leak coolant out of the weep hole a lot. Cat tried numerous repairs. One was trying a plastic impeller and it would break away from the metal center and free wheel. So they asked the 3200 product group ( I was told this), how come your water pump don't leak coolant? The reply was that the water pump spins so fast, it pulls the coolant away from behind the impellar and the seal runs dry. So no coolant to lubricate the seal, the seal fails over time. So the 3400 product group had a groove cut along the housing to allow coolant to flow across the face and lubricate the seal. Our mouse story, our chassis dyno fuel cell failed. Found that a mouse would lay on the fuel card in the winter time to stay warm. The mouse used the bathroom on the card and smoked a 5K card.

[@AdeptApe]

That's an interesting story about the 3200 series. I bet all those guys are retired now.

[@johngoldsmith6629]

@@AdeptApe Also shunt line fitting is critical on which port to put it in. The rear is the best, second is this location. The top will cause problems and should never be used.

[@justinsane7128]

Amazing work Columbo

[@2secondslater]

A shop I worked at that had pretty poor housekeeping had some bundy tube, a roll of it, sitting around for years. One day I use it to make a brake line on a customer's car, could not get the line to bleed, no fluid through the line at all. Turns out that ants had got inside the tube, I mean lots of them, died inside it and turned into a solid ant mass blockage. Open ends invite creepy crawlies.

[@Marcus_from_OZ]

I've seen mice eat out an air filter and block/destroy a turbo, strip all of the padding from inside a cab, seats and trim, ants eat all of the resin out of an ECU and the insulation from a wiring loom, birds nest in the exhaust of a D6 to the extent that the C9 couldn't move it under it's own steam and the heat exchanger intakes on a 65' cruiser blocked with prawns (Shrimp?) completely destroying a pair of 3208T's, but that's a new one.

[@CMSgtSanders]

Thanks for teaching me more about my engine. As always great video.

[@bombud1]

Its nice to know the other shop didn't cut corners or reuse old parts. Just bad luck.

[@johngillon6969]

My brother once stored his 1969 jaguar XKE in some one's garage for a period while he was assigned in the airforce to alaska. when he returned two years later and tried to start the car, he broke the crank shaft because some mouse had packed one of the cylinders full of dry dog food. the mouse simply climbed in the exhaust pipe and filled the cylinder after coming thru the exhaust pipe muffler the exhaust manifold and then thru the open valve. If i had not been there i would not believe this story either.

[@84Prerunner]

Had a similar but possibly less graphic scenario happen to me. Bought a used engine, installed it and it would over heat instantly under load. Thought it was an air pocket, pulled the radiator cap and saw a sunflower seed floating on top. Strange Fished it out, started it with the cod off and as it started puking water out from heating up more sun flower seeds started coming out! Drained the system, pulled the thermostat housing (on the lower hose on this application) and found it completely packed full of sun flower seeds! Some had somehow made it past the thermostat while it ran but it was blocking cooling flow. The inlet to the thermostat housing is about 6-8” long, my guess is while the engine sat a mouse made a home inside.

[@ohcrap3263]

Best I saw was a shop rag left in the lower radiator outlet. The cat dealer was not pleased. I used a diagnostic procedure they taught. ( Temperature differential between radiator inlet and outlet).Good times.

[@johnniezuniga6841]

You are the best thank you for sharing all your knowledge on all your other videos thank you very much take care and God bless

[@HANKTHEDANKEST]

OH MY GOD, OF COURSE IT WAS A MOUSE! Civilized man's oldest adversary: the humble mouse. Gets into your grain, eats it, everybody dies. Gets into your wires, eats them, everything gets fried. HIDES OUT IN THE COOLING SYSTEM? Just... goddamn it. Nice "catch" Josh, looks like you've been promoted to chief mouser at Western States!

[@abrahambotha6350]

Once had a tractor with a vibration, after disassembling top/bottom and much head scratching, sent to agents etc etc The tractor worked in heavy clay soils, dust and water had formed clay and hardened on cooling fan blades.

[@ianloy1854]

Reminds me of a 3208 in a Ford Cargo that was brand new but had been in storage for about 2 years. It overheated horribly. When it was pulled apart to find out what had gone wrong it was found that EVERY coolant touching surface was lowered by ~20 thou (0.5mm). Not only that but the block was full of rust. The coolant had turned acidic for some reason over the storage period and attacked all of the iron (block and heads) eating it away perfectly.

[@kxp.1496]

They must have used Chinese coolant

[@nuggetwv5302]

I've never heard of that. But that will be on for the books.

[@johnduncan9749]

That mouse seen that big block of yellow cheese and could not resist.

[@anonymuswere]

*LOL!* a Cat caught a mouse! I'm sharing this with my friends in the trucking industry. man, there's just some things you can't fully prevent. it probably went after the shop rag for nesting material.

[@michealhohenberger589]

That was interesting. I myself am fighting a heating issue. Not sure if it thermostats or water wheel, or just faulty temp sensors.

[@markgeyer3591]

Wow 👌...Didn't See that Coming!..Great Video

[@los8373]

When Freightliner stop working on Cat’s, I only trust Ring Power Cat in Riverview Fl to work on my C15 NSX. I had a terrible experience at Rush in Tampa.

[@daviddroescher]

6:50 The line Indicates an air pocket in the water pump . You can see the distinctive difference between the corrosion where the air was versus where the corrosive fluid was. Now to finish watching to find out why the fluid was so corrosive having Corrosion inhibiting additives in brand new coolant.

[@timothyroatenberry1274]

My brother bought a 70 Chevy pkup one time, got to smoking bad on the way home, he pulled over check it out, reved it up several times, blowed a mouse nest out of the exhaust, run fine after that ! Those things get in the damdest places !

[@larrytalley117]

Fun and informative video! Love these videos from the Ape!

[@AdeptApe]

Hi Larry! You were early on this one.

[@larrytalley117]

@@AdeptApe I used to have over heating issues with my C7 right after buying my RV. Found the acrylic surge tank, which is part of the cooling pressurized system had a split at a seam, causing the system to not hold pressure. That was not hard to find since it was spraying coolant everywhere. I replaced the tank, but still had some over heating issues. Next was to have the cooling system flushed and filled with new coolant. It was better but temps would still rise when climbing up hills. What I discovered was that I was exacerbating the issue with how I was driving. My C7 has a direct drive fan, and I was allowing the engine rpm to get too low under when climbing. The Allison transmission was not down shifting far enough to keep the rpm’s above 1500 to 1800 rpms. Actually I found a sweet spot at 2200. This reduced the load on the engine and forced enough cooling air through the radiator. Remember the engine in a diesel pusher is actually mounted backward and my radiator is in the rear, not side mounted. Side mounded radiators usually have electric or hydraulic driven fans and are not necessarily rpm connected. Maybe this will help someone else with an older C7.

[@jackking5567]

Mice: I have a shop vac that's left in a corner during working hours. Occasionally, the vac comes out and the shop is cleaned down. Well, one Winter the shop was out of action due to us moving things around for a better layout. Come the end of the moving, we hauled the shop vac out to clean up - it was Spring time by then. Anyway, the vac worked well but after 30 minutes or so we noticed a terrible smell. We just couldn't place it and even had a drain team out because we thought a sewer was cracked beneath the floor. The smell was beyond comfortable. Eventually we located the smell. The shop vac had laid idle for several months and its long hose lay connected to the machine but coiled around it on the floor. During the colder months, a large family of mice took residence inside the shop vac. The long hose was their means of entry. We lay vermin control poisons in some places and it appears a mouse hauled a large chunk of said poison into their safe family home for their family to munch on - it wiped them out inside the vac. Us then using the shop vac had warmed the machine up once we got really going. The warm air had broken apart the soft mushy remains of a large number of rotten mice and the spent air exiting the shop vac had then filled the workshop space. We'd been breathing in rotted soggy soft mouse fumes. I'm almost bringing my breakfast up telling this story. Always check inside the shop vac before use folks. Our shop vac was so badly messed we had to throw it away.

[@invisiblekid7374]

This has got to be one of the weirdest if not the weirdest vehicle problem I’ve ever heard of. On any vehicle ever! Crazy!!

[@robertwatson818]

Years back I saw this in another "rebuild". A rag was left in the engine during the reassembly. Same symptom--overheating.

[@davidsignor7931]

I have saw plenty of fresh overhauls on Cats come back overheating most common cause is a rag was left in the lower radiator pipe water pump grinds it up and it plugs up the face of the oil cooler

[@jackvisn]

It reminds me of the Air Traffic Controllers joke. "You land 10,000 planes safely nobody remembers...have one small mid-air collision and nobody forgets". The odds of this are small and plugging every hose/hole during a rebuild aren't feasible. Good thing the engine was shut down before damage. We have all seen acorns in airboxes. That mouse had a bad day!

[@KevinJones-pj8kx]

I had a cat that suddenly began overheating on us. I was at a new to me shop and had limited cat inline experience. In the end I found a split water pump impeller. I found a lack of the flow pressure you spoke of to find the broken water pump. New pump and problem solved. That was the first time I ran into a broken impeller.

[@iaial0]

Maybe a casting defect?

[@billcovert3473]

Redding Freightliner had Detroit 60 series with high crankcase pressure. Older engine, road draft hose plugged shut with porcupine quills.

[@AdeptApe]

How the, what?!?!

[@billcovert3473]

@@AdeptApe Yeah, it looked like a pin cushion, quills packed with dirt. Just a animal story. Not near as cool as this one.

[@refusemech]

Hi Joshua. I noticed that this truck has OAT coolant in it and looks like a pre emissions engine. I maintain a fleet of refuse trucks and attempted to use OAT coolant but I found it isn’t compatible with copper radiators and some gasket materials. Even after thoroughly flushing the cooling system before filling with the red coolant we started having leaking issues. And after early replacement of radiators from core failures. I’ve been flushing and replacing with glycol coolant. I don’t recommend OAT coolant for older trucks. If interested I can post some pictures of what I’m experiencing.

[@Graham_Langley]

You may have just answered what happened to a car I had some 25 years ago when its copper rad core turned into a collander. At the time it was young enough for there to be value in getting a full a dealer service history. They'd changed the coolant at two years then just before the next change this happened. They put a new rad in but charged me for labour (UK). I've now looked it up and indeed OAT antifreeze and copper are incompatible, so it looks like it was probably what they put in and it may even have had it in from new. Many thanks!

[@jimmotormedic]

I was going to say another cat choking on a hair ball story. But I have a feeling this is going to go on a while

[@elcaminomant]

Haven't seen that yet but I sure can believe it!

[@bradleyauman279]

Wow that's so crazy another great video keep up the good work Sir you are very good at what you do

[@bobyk87]

Wow, most awesome recent diesel engine story ever.

[@shaneshane1379]

Had that problem before. The down line from the coolant tank the the pump inlet was stopped up at the tank fitting. The customer put 5 bottles of that ceramic sealer in the cooling system.

[@sjg4967]

The Cat Columbo... Always gets his mouse....! Awesome.

[@gutsngorrrr]

Wow, I was not expecting that one.

[@Drmcclung]

Seeing an animal in there, that's 100% new! I've seen this rust a time or two before after fresh rebuilds; Cause #1 is some mechanics filling up with just tap water only (that's OK, keep reading) just to get ALL the swarth & crud out, and make sure everything is working right before draining & dumping 15 gallons of coolant in the engine after the very first 1 or 2 heat cycles on water, yet don't get *all* of that tap water out and whatever's in the *tap water* reacts with metal & coolant for some very nasty compounds. Cause #2 is mixing tap water with concentrate rather than distilled I saw that mistake way more than anything else - suddenly thermostats aren't lasting very long, radiator cores crusting up and not cooling efficiently. Not near as bad as 100% water but still no good. I've seen a red shop rag completely wound around a water pump impeller before. Don't f*ck up cooling systems young mechanics, we all make that mistake at least once in our careers 😁

[@deanh7190]

Proving once again that an adept ape shall overcome a cool mouse 🤣. Very interesting video👍