Do a compression test on the cylinders on the side of the motor with the "good" head gasket (assuming both did not fail). That should give you some indication of the status of the piston rings.
Help! Got the dreaded call - need a new motor!
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Somebodyelse5
16124-75030
It should, I know it's found it's way into some pre-taco toyota trucks. @Kleen60 is putting one in his 60.
I'm sure even bigger would fit into a 100 series. I think a 5.9L 6BT would be pretty cool in a 100, but that may be to big to squeez in there...
Clutchee
I'm fun sized!
Contact George orangefj45
Great dude and amazing cruiser shop owner.
Great dude and amazing cruiser shop owner.
Could be a bit underpowered for the 100 series, no? Are they not producing an 8 cylinder crate engine?
The Toyota 4.2 diesel ain’t bad that Toyota fit in the 100, it would certainly fit easy enough, same motor mounts and transmission.
Please don’t take the advise of a repair, hopefully the mechanic you take it to will give you good advise. You might be lucky and it is fine, it might even work for 6 months and then something goes wrong. A cooked engine can be repaired but the cost of a full inspection to verify the total damage just isn’t worth it. By the time you remove the cylinder heads, check for bent con rods, damaged cylinder walls, piston skirts, piston rings, crank bearings,camshaft bearings, warped cylinder heads. The cost just isn’t worth it as these are not rare motors that need a full rebuild.
It is a lot quicker to pull a engine out than it is to remove cylinder heads so I cannot see the advantage of a repair, plus it can be warranted in some form in having a replacement engine. What mechanic would warrant a cooked engine that doesn’t get fully checked out. The engine overheated because the coolant was lost from the engine block, the coolant temp sensor doesn’t see this as the coolant isn’t there to take a reading from, the cylinder temps raise so much that the aluminium cylinder head warps as it has a different thermal expansion to the iron block, same goes for any of the other mismatched metal components.
I do agree that motors with bad headgaskets can get repaired successfully, but not so much when the cause of the headgaskets failure was a sudden loss of coolant. High Cylinder temps through loss of coolant from the heater Tees is the cause of the issue, not just a bit of pressurisation from combustion gases entering the cooling system as in a normal headgasket failure.
Please don’t take the advise of a repair, hopefully the mechanic you take it to will give you good advise. You might be lucky and it is fine, it might even work for 6 months and then something goes wrong. A cooked engine can be repaired but the cost of a full inspection to verify the total damage just isn’t worth it. By the time you remove the cylinder heads, check for bent con rods, damaged cylinder walls, piston skirts, piston rings, crank bearings,camshaft bearings, warped cylinder heads. The cost just isn’t worth it as these are not rare motors that need a full rebuild.
It is a lot quicker to pull a engine out than it is to remove cylinder heads so I cannot see the advantage of a repair, plus it can be warranted in some form in having a replacement engine. What mechanic would warrant a cooked engine that doesn’t get fully checked out. The engine overheated because the coolant was lost from the engine block, the coolant temp sensor doesn’t see this as the coolant isn’t there to take a reading from, the cylinder temps raise so much that the aluminium cylinder head warps as it has a different thermal expansion to the iron block, same goes for any of the other mismatched metal components.
I do agree that motors with bad headgaskets can get repaired successfully, but not so much when the cause of the headgaskets failure was a sudden loss of coolant. High Cylinder temps through loss of coolant from the heater Tees is the cause of the issue, not just a bit of pressurisation from combustion gases entering the cooling system as in a normal headgasket failure.
And we will.
You are 100% wrong. Combustion gases entering a cooling system does not make it overheat. Does it pressurize the cooling system? Yes. But it does not overheat. The combustion gases are cooled by the coolant.
Somebodyelse5
16124-75030
The R2.8 would definitely be a bit small for the 100, but the 6BT is a monster and a quick search shows a few 80's that have done the swap. 11 Reasons Why the 12-Valve Cummins Is the Ultimate Diesel Engine | DrivingLine
Man, you guys got some crazy ways of thinking here.
I never pay mechanics to do stuff, so I don’t get a lot of the ways of thinking or costs, maybe. But when something overheats, you go ahead and change the easy stuff and see if it still overheats. Also, a compression test to see if headgasket is good.
Lots of different ways a headgasket can fail. Can dump coolant into cylinders, or just leak compression between cylinders, or leak coolant to outside, or leak oil to outside, or all kinds of weird things.
Nah, never trust just some guys word on hearing a ‘knock’. People hear all kinds of weird noises when they want to hear something. Could be an exhaust gasket or heat shield rattling, or any kind of dumb stuff.
If easy stuff doesn’t fix it, and it points to head issues, just unbolt a head or both and check it out. If engine is screwed anyways, it doesn’t hurt much just to unbolt head and look for crack or warp age. Have machine shop look it over if you can’t see damage yourself.
And yeah, I’ve overheated the ever loving crap out of my old bmw engine, re-did the head and put it back, and drove it many years and cross country and never any issues. If rings do get worn, they just use a little oil and make a little smoke. Still can run damn strong. Not really a catastrophic issue.
If bottom end is screwed, then yeah it’s a big job, but not an impossible one if you got skills or friends willing to help. You can always pull bottom end, send it to a machine shop and have them do a fresh rebuild. Not sure why so many people worry about picking out good used engine. Is it really that hard to change some rings and bearings in this engines and have it like new?
I never pay mechanics to do stuff, so I don’t get a lot of the ways of thinking or costs, maybe. But when something overheats, you go ahead and change the easy stuff and see if it still overheats. Also, a compression test to see if headgasket is good.
Lots of different ways a headgasket can fail. Can dump coolant into cylinders, or just leak compression between cylinders, or leak coolant to outside, or leak oil to outside, or all kinds of weird things.
Nah, never trust just some guys word on hearing a ‘knock’. People hear all kinds of weird noises when they want to hear something. Could be an exhaust gasket or heat shield rattling, or any kind of dumb stuff.
If easy stuff doesn’t fix it, and it points to head issues, just unbolt a head or both and check it out. If engine is screwed anyways, it doesn’t hurt much just to unbolt head and look for crack or warp age. Have machine shop look it over if you can’t see damage yourself.
And yeah, I’ve overheated the ever loving crap out of my old bmw engine, re-did the head and put it back, and drove it many years and cross country and never any issues. If rings do get worn, they just use a little oil and make a little smoke. Still can run damn strong. Not really a catastrophic issue.
If bottom end is screwed, then yeah it’s a big job, but not an impossible one if you got skills or friends willing to help. You can always pull bottom end, send it to a machine shop and have them do a fresh rebuild. Not sure why so many people worry about picking out good used engine. Is it really that hard to change some rings and bearings in this engines and have it like new?
What is so crazy, the op said he is going to take it to a repair shop, so I take it that he isn’t happy to do the work himself. I can do it myself, but respect others that can’t or just don’t want to. The easy stuff has been replaced as in the heater Tees. A engine replacement is easier than a head gasket change, so the engine change makes the job easier. Do the easy stuff first.
The whole head gasket change is harder than an engine change is one of the things that just make any damn sense at all, even if you go to a mechanic. You’ve got a couple grand in a used engine, plus a whole ton of labor disconnecting and reconnecting accessories and crap with a hoist, etc.
A headgasket is cheap part, you take timing stuff out of the way, unbolt it, send it to machine shop to get checked out for a couple hundred bucks, then torque it down by following the proper sequence. Fresh fluids and done. I’ve even done headgaskets on a Subaru boxer, which is way more hassle than most upright engines.
Also, unless these Toyota engines are super weird, no idea how you’d hurt any bottom end bearings by or make any knocks by just that little bit of overheating. People cook headgaskets and intake manifolds all the time in normal cars, and run it with oil looking like chocolate milkshake from all the coolant in the oil, and a lot of times you can just drain oil and coolant, fresh gaskets and fluids, and it’s good. If your oil doesn’t look like a chocolate milkshake, then there’s not much risk at all.
A headgasket is cheap part, you take timing stuff out of the way, unbolt it, send it to machine shop to get checked out for a couple hundred bucks, then torque it down by following the proper sequence. Fresh fluids and done. I’ve even done headgaskets on a Subaru boxer, which is way more hassle than most upright engines.
Also, unless these Toyota engines are super weird, no idea how you’d hurt any bottom end bearings by or make any knocks by just that little bit of overheating. People cook headgaskets and intake manifolds all the time in normal cars, and run it with oil looking like chocolate milkshake from all the coolant in the oil, and a lot of times you can just drain oil and coolant, fresh gaskets and fluids, and it’s good. If your oil doesn’t look like a chocolate milkshake, then there’s not much risk at all.
YardPig
SILVER Star
Oil control rings are thinnest and first to lose their tensile strength. Cylinder bore condition and compression readings are no indication if the engine will now consume oil.
You have two cylinder heads to remove to get checked out. The engine didn’t just overheat as in the temp gauge was to high, it was cooked because the coolant had gone. The reason I say cooked is that the engine as in cylinder temps got so hot that it damaged itself with no coolant keeping it in check. Overheating because of a headgasket failure is a different scenario as your cylinders would still have some coolant around them controling them just then your coolant has just got a bit hotter but your cylinder temps are reasonable. Without coolant how do you know how hot anything got, that is the problem, the temp gauge doesn’t read combustion chamber temps so saying it overheated a little bit is unknown to anyone as the gauge won’t help you work that out. It definantly got hot enough to warp the cylinder head in a short period of time which is the worry. Again milkshake oil is another scenario, it isn’t the same as running a engine dry without coolant. If the coolant was still there then I would agree, but why would the headgasket go bad because the heater Tees went if coolant lose wasn’t the case.
YardPig
SILVER Star
Combustion gases will displace coolant out of the system, into the overflow bottle and onto the ground. Hot air rises, this isn't difficult to comprehend. Lack of coolant is air, hot air is steam. If you'd like to continue to refill your cooling system and live with bubbling and gurgling coolant bottles, insane coolant temperatures and coolant being pushed out of the system, have at it.
https://www.quora.com/How-does-overheating-damage-a-car-engine
Not saying it is 100% correct, but back in the day when I used to do engine rebuilds this seems factually correct.
Also, head gaskets failures don’t always cause overheating, they might just introduce air into the heater core so the system needs to be burped often, but most of the time it does as described by @YardPig.
Not saying it is 100% correct, but back in the day when I used to do engine rebuilds this seems factually correct.
Also, head gaskets failures don’t always cause overheating, they might just introduce air into the heater core so the system needs to be burped often, but most of the time it does as described by @YardPig.
So you agree, blown head gaskets do not cause overheating. Loss of coolant does.
Does a blown head gasket cause coolant loss? It sure does. Coolant is burned in the combustion chamber. Thats why it smokes out the tailpipe.
But a blanket statement that combustion gases getting into the cooling system cause the engine to overheat is false. The gases do not cause overheating. Coolant loss does.
The OP has a full cooling system. His suspected blown head gasket is not causing his overheating.
YardPig
SILVER Star
No, now your just having a conversation/and or an argument with yourself. A head gasket can be "blown" in many ways, between firing rings into other cylinders, seepage into coolant or oil passages, external leaks both coolant or oil. Now your trying to confuse the conversation with smoking out the tailpipe. We were not discussing 'swallowing' coolant.
The OP was clear - "...the smoke was the steam from the coolant hitting the hot engine...".
His mechanic confirmed after he refills and bleeds the cooling system he has combustion gases entering the cooling system, which was confirmed from a combustion leak detector fluid and that it overheats after 10 minutes. The test doesn't lie.
So lets say your engine coolant is 180-220ish Celsius as a rough figure and the temperature in the combustion chamber is 600 or 700 Celsius (heaven forbid he put a load on the engine and watch those numbers climb), you honestly want people to believe that your engine coolant can absorb that difference and maintain control when you introduce those combustion gases into the cooling system?
Anyhow, I guess you must have nailed it, he needs an oil change and a thermostat and he can drive to the moon...
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It is a heavy iron block with aluminum heads. Aluminum heads on an iron block are always the first thing to go. The OP's wife stopped because of the sound of the pipe bursting and saw the coolant leak. I don't think the motor was driven far enough to kill oiled parts because it had no coolant in it. Mechanics do head gasket replacement all the time, not motor replacement. I've had high strung 4-bangers blow HGs ... yank the head, get the deck checked for level and cracks, put it back on or replace it, good to go. Same recommendation here. Yanking the entire iron-block motor that was stopped because it was noticed the coolant was going all over and tossing in an unknown used motor for at least $4k in parts and labor is not a smart way to spend your money, IMHO.
My advise is there, take it or leave it to the op, I have said my piece. I will add that a replacement motor should carry some warranty, plus isn’t 4K a bit expensive. I would prefer to be proven wrong than anyone to have egg on there face if the op now decides to go for a repair.
