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Well, this is what has work for me when replacing a thermostat that's located near the top of the engine, and connected to the top radiator hose:
Drain enough antifreeze to bring the level below the thermostat housing, unless I wan to replace the antifreeze, in which case I drain it all. Then replace the thermostat making sure that it is not installed backwards, refill the radiator, turn the heat control in the cab to hot, and run the motor for a couple of minutes, then add more antifreeze as needed, and bleed air from the system (including the top radiator hose). I run the motor again for a couple of minutes, and check the antifreeze level once more. If it needs more antifreeze, it means that it also had air trapped in the motor or radiator, so I continue this process until all the air is bled from the system.
This to watch out for when replacing a thermostat, or just when the temperature gage fluctuates as described by the OP:
a. Electric fan operation
b. Thermostat
c. Water pump
d. Radiator cap
e. Antifreeze/distilled water ratio
a. I run the motor until it reaches operating temperatures. The fan should come on every time that the temperature nears the high temperature level
b. Proper installation of the thermostat, and air bleeding from the system. If the problem continues, I remove the thermostat and run the motor this way to see what happens.
c. All water pumps have a bleed port near the bottom of the housing. If you see any antifreeze drop in there, it means that the pump should be replaced.
d. Try another radiator cap if needed. This is obvious. But I have never had a radiator cap leaking and causing the motor to overheat.
d. Where I live it gets extremely cold, and one has to pay close attention to the antifreeze/water ratio. You have to decide if purchasing a pre-mixed antifreeze, which usually has a 50/50 ratio, or pure antifreeze. If you purchase that later, make sure that you don't mix it more that 60% antifreeze/40% distilled water (this is true for places where it gets very cold). Antifreeze loses its anti-freeze properties if mixed past 70% antifreeze/water. You can mix it past 60% if you have the proper tools, but I would not trust the cheap testers sold at most automobile parts stores. Anyway, 70/40 would be the maximum to go if you want to go that route, but 60/40 is the safest.
It is losing water, I don't know where, but that is the issue. Somewhere, somehow, it is losing water, as in the radiator will be bone-dry within 5-odd miles. (Previously the water would boil-over into the overflow, now it just goes away altogether.) I can see NO splits in any hose or the radiator so I don't know if the water pump is maybe losing it or the radiator is but only once you get going and the pressure increases. (I have questioned if it's losing it via the overflow tank because I misplaced the O-ring that seals up the overflow tank's cap.) I intend to rent the pressure test thing from Autozone to try and see where the leak is coming from. Question--if you have a blown head gasket, would that itself cause it to leak right from the head?
I replaced the thermostat again. My idiot in-law said he thought the upper radiator hose, which had never given me any trouble, was "pinched" and he insisted on cutting some off. On the way home during a trial run, that hose kept coming off and causing it to lose all the water. Worse, the gauge was reading 3/8 hot so I thought nothing was wrong until I heard the engine knocking and saw what I saw. I fixed that issue, but it's not over at all.
Before it had occasion to be somewhat difficult to start if it had just ran hot, that has worsened. It sat for hours at home while I was at work, I got home and got it going within less than a minute, but then shut it off not even a minute later to redo the drill of adding water after bleeding the air line, and it was so freaking hard to get it started, even though it was cool. It took probably 20 minutes to get it going.
Once I got it going, I went down the road and just as before within 4-odd miles or so it was going towards hot, not full-blast H but very close, fluctuating from that to around 1/2, and going back and forth, after 8-9 miles or so it was very much at least 7/8 towards the hot. I got home right away and parked it, opened up the radiator tank right away (yes I know, risky)--dry as a bone, and the overflow tank was dry as well. (Again, prior to this, the water would go into the overflow and I could go a good 15 miles without it running hot, just pump the water out of the overflow when it cooled, and it only took maybe 1/4 of a gallon to refill the main tank.) Again the fans do come on, and shut off after parking and it's cooled off (around 2 minutes or so).
Even from day one the people at Autozone did observe a slight leak near the top of the radiator, I suppose maybe it's become worse but even with it full and running in the parking lot I can't see any coming out, in fact I can't see any coming out anywhere. I suppose it takes highway speeds to do so but once it does boy does it ever. I'm perplexed, really.
It is losing water, I don't know where, but that is the issue. Somewhere, somehow, it is losing water, as in the radiator will be bone-dry within 5-odd miles. (Previously the water would boil-over into the overflow, now it just goes away altogether.) I can see NO splits in any hose or the radiator so I don't know if the water pump is maybe losing it or the radiator is but only once you get going and the pressure increases. (I have questioned if it's losing it via the overflow tank because I misplaced the O-ring that seals up the overflow tank's cap.) I intend to rent the pressure test thing from Autozone to try and see where the leak is coming from. Question--if you have a blown head gasket, would that itself cause it to leak right from the head?
I replaced the thermostat again. My idiot in-law said he thought the upper radiator hose, which had never given me any trouble, was "pinched" and he insisted on cutting some off. On the way home during a trial run, that hose kept coming off and causing it to lose all the water. Worse, the gauge was reading 3/8 hot so I thought nothing was wrong until I heard the engine knocking and saw what I saw. I fixed that issue, but it's not over at all.
Before it had occasion to be somewhat difficult to start if it had just ran hot, that has worsened. It sat for hours at home while I was at work, I got home and got it going within less than a minute, but then shut it off not even a minute later to redo the drill of adding water after bleeding the air line, and it was so freaking hard to get it started, even though it was cool. It took probably 20 minutes to get it going.
Once I got it going, I went down the road and just as before within 4-odd miles or so it was going towards hot, not full-blast H but very close, fluctuating from that to around 1/2, and going back and forth, after 8-9 miles or so it was very much at least 7/8 towards the hot. I got home right away and parked it, opened up the radiator tank right away (yes I know, risky)--dry as a bone, and the overflow tank was dry as well. (Again, prior to this, the water would go into the overflow and I could go a good 15 miles without it running hot, just pump the water out of the overflow when it cooled, and it only took maybe 1/4 of a gallon to refill the main tank.) Again the fans do come on, and shut off after parking and it's cooled off (around 2 minutes or so).
Even from day one the people at Autozone did observe a slight leak near the top of the radiator, I suppose maybe it's become worse but even with it full and running in the parking lot I can't see any coming out, in fact I can't see any coming out anywhere. I suppose it takes highway speeds to do so but once it does boy does it ever. I'm perplexed, really.
If you are SURE that you are not leaking coolant, but your system is going dry...........that is most likely one of the following: bad-head-gasket/cracked-head/cracked-block. This engine-defect is causing the coolant to be sucked into the engine, where it is burnt.
If you get the engine up to operating temperature, your cooling-system will be pressurized. Then you can very carefully go-over the cooling system with a flashlight.....any leaks will be apparent. If you find no leaks when your system is pressurized.......that coolant-loss is most likely from an engine-defect.
If you are SURE that you are not leaking coolant, but your system is going dry...........that is most likely one of the following: bad-head-gasket/cracked-head/cracked-block. This engine-defect is causing the coolant to be sucked into the engine, where it is burnt.
If you get the engine up to operating temperature, your cooling-system will be pressurized. Then you can very carefully go-over the cooling system with a flashlight.....any leaks will be apparent. If you find no leaks when your system is pressurized.......that coolant-loss is most likely from an engine-defect.
Thanks for the help. Today I got it fired up and ran it until it became 3/4 hot, then I shut it down (it took maybe 5 minutes for that to occur). My observations:
(1) The lower radiator hose, the one with the thermostat, it remained cold during that "run." (On the other hand, yesterday when coming home and pulling over, the hose was warm, but today it's cold, and it's been cold much of the past 3-odd days as well.) The upper radiator hose was hot as heck.
(2) The water, during this run, was "bubbling" into the overflow tank, but when driving it home yesterday, the overflow tank was dry as a bone, prior days it was "bubbling over" into the tank when driving.
(3) I could see no leaks anywhere, but then I'm known to not see the obvious on occasion.
(4) On prior occasions, especially once things were starting to heat up, you could smell antifreeze in the A/C vents if it was on. On the other hand, for a short period anyway, after the guy put on the belts after they broke, for a day or two there was no smell.
If I rent a pressure tester from Autozone and can find no leaks, am I to assume it's as you say? If that's the case, forgive me if I sound dumb (too late I know, ha ha), but would the engine via the blown head gasket burn through an entire radiator's worth of water within barely 5 minutes? That sure seems awful fast.
Thanks for the help. Today I got it fired up and ran it until it became 3/4 hot, then I shut it down (it took maybe 5 minutes for that to occur). My observations:
(1) The lower radiator hose, the one with the thermostat, it remained cold during that "run." (On the other hand, yesterday when coming home and pulling over, the hose was warm, but today it's cold, and it's been cold much of the past 3-odd days as well.) The upper radiator hose was hot as heck.
(2) The water, during this run, was "bubbling" into the overflow tank, but when driving it home yesterday, the overflow tank was dry as a bone, prior days it was "bubbling over" into the tank when driving.
(3) I could see no leaks anywhere, but then I'm known to not see the obvious on occasion.
(4) On prior occasions, especially once things were starting to heat up, you could smell antifreeze in the A/C vents if it was on. On the other hand, for a short period anyway, after the guy put on the belts after they broke, for a day or two there was no smell.
If I rent a pressure tester from Autozone and can find no leaks, am I to assume it's as you say? If that's the case, forgive me if I sound dumb (too late I know, ha ha), but would the engine via the blown head gasket burn through an entire radiator's worth of water within barely 5 minutes? That sure seems awful fast.
Smelling coolant in the interior-vents is most-likely from a leaky heater-core.
The pressure-tester will let you know if you have a leak.....just pressurize the system, making note of the PSI that you pressurized it at. Then go look for leaks......when you are done doing that, look at the pressure-gauge again, it should not have dropped.
Worse, the gauge was reading 3/8 hot so I thought nothing was wrong until I heard the engine knocking and saw what I saw. I fixed that issue, but it's not over at all.
Yeah, that's not good. Have you checked the oil? I'd look for a milkshake like consistency. If that's what your oil looks like, you've either warped the head or cracked the block.
Yeah, that's not good. Have you checked the oil? I'd look for a milkshake like consistency. If that's what your oil looks like, you've either warped the head or cracked the block.
That's funny, the oil has never looked like that, at least as best as I can tell. The white smoke from the exhaust--got that. The cold air blowing even in heater mode--got that. All of the coolant eventually being gone sometimes within 8-10 minutes, but with no leaks that I can see anyway--got that. The coolant boiling over into the overflow--before it starting disappearing (burning in the engine block now apparently), I HAD that. Foam in the overflowed coolant, when it overflowing into the coolant tank, it seemed to be doing that.
But no, I've never noticed milkiness in the oil dipstick.
Today, as a last ditch effort, I tried some K&W Block Sealer. I followed the directions and am letting it sit for 24 hours before I do a trial run. I did see some encouraging signs--when I got the car home Saturday (when the upper radiator hose was coming off) and I tried to crank it, it was VERY hard even though it had now been several hours. Today, it cranked easily. A day or two ago, with the car at home, I cranked it and after 10-odd minutes or so it was running hot even in the driveway. Today it didn't run hot at all the entire 30 minutes. Also, previously (upon getting it home) when running it even when parked all of the water would eventually be gone, the radiator would be empty. Today, after the 30 minutes were over and I'd shut the engine off and let it cool, I went to drain the radiator and LOTS of water came out, it didn't all leak out or burn off as it had before.
I'm crossing my fingers, hoping it worked good enough to buy me some time. I know it's a Band-Aid solution, but if it does nothing more than allow me to keep using this car for about another month, so be it, at this point I'll take it.
You are spending cash on additives and running your engine hot until it runs out of coolant and knocks. At what point would you consider taking your car into the shop?
Maybe do a basic clean of your engine bay. This plus a UV leak additive kit will make leaks obvious. Also, why not bring it up to temp parked so you can maybe see what's happening in the bay? Let it idle up to temperature, then bring it to 2-3K RPM until the fans come on, at which point the cooling system is engaged.
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