Toyota radiators

Same/similar thing happening to Ford 3 cylinder Ecoboost engines resulting in fires and recalls.... apparently the fix is to install a coolant level monitor......

Many owners complaints of losing coolant completely without any lights or w arnings. In my case, the temperature shot up briefly, then back to normal. I stopped and checked the overflow tank, and it was full. With a big hol e like that, the radiator was empty out without sucking coolant back from t he tank. I was not going to open the radiator cap anyway. Coolant level s ensor in the overflow tank would not work.

On Thursday, October 18, 2018 at 12:54:35 PM UTC-4, snipped-for-privacy@gmail.com wr ote:

warnings. In my case, the temperature shot up briefly, then back to norma l. I stopped and checked the overflow tank, and it was full. With a big h ole like that, the radiator was empty out without sucking coolant back from the tank. I was not going to open the radiator cap anyway. Coolant level sensor in the overflow tank would not work.

You'd think the coolant temperature would be a clue, but it actually measur es the coolant temperature. If that is gone you have to wait for the head or block temperature to rise and by then the vital parts are well overheate d. So clearly a coolant level sensor is required. This could be done via pressure measurement which would also detect loss of water pump activity su ch as a broken fan belt. Of course loss of coolant pressure would also tri gger the coolant temperature sensor, but only after it gets hot which can a lso be too late.

Sometimes I find it amazing that they will shave literally $0.10 off the co st of making a $30,000 auto by sacrificing some function.

Rick C.

It is definitely a cost saving design defect. They might have been using b rass pipe and fitting, and switching to soft aluminium, without doing the e ngineering works. It would probably cost $500 on 1 million vehicles to ret rofit, plus $5000 for owners with a dead engine. I guess Toyota is learnin g from Detroit in downsizing quality.

it does what it says on the tin.

if there's any sensors on that.

no. water pumps make very little pressure. most of the pressure is from steam. and the steam pressure will stay high until there's no water left to boil you need to measure actual water level. use a sealed capacitive sensor. You could measure flow but the thermostat is going to mess with that.

in a sudden loss of pressure It'll go down initially as the coolant near it boils, then you'll have to wait for heat to get to the sensor, you might have to wait until the engine catches fire for that.

Which "tin" would that be??? My gauge just says "temperature" and the assumption is that is telling me if the engine is overheating. Therein lies the problem... The technology is doing an easy job rather than the needed job.

Duh! Where do you think they put the temperature sensor???

No one cares if the pressure is small, there is differential pressure which is what makes the water flow. It can be measured. Steam isn't the same thing at all.

I don't agree. Measuring differential water pressure will tell you if there *is* water to be pumped and if the pump is working.. two very important pieces of info.

Lol I've had my temperature sensor alert me many times of low water level. It's not the best way, but it works. If the pressure releases suddenly your first sign is the big cloud of steam from under your hood.

Rick C.

I've read some drivers just bypass the transmission coolant loop thru the main radiator, or put in a small aftermarket cooling block. I don't think all manufacturers even put a transmission loop thru the radiator, stock, at all depending on vehicle, more common on SUVs and trucks and with "towing packages" on sedans.

Unless you're regularly towing stuff up and down steep grades in the summertime the transmission fluid likely doesn't need that much cooling anyway in most situations

Could always just drop in an aftermarket replacement radiator temporarily, they're like 100 bucks China special, that doesn't have a transmission loop and bypass it for a while while monitoring/logging the transmission fluid temperature via OBDII. if everything still looks good for how you usually drive the vehicle then just leave it that way and fuggedaboutit

That idiom means that is it is as described.

On the outer skin of the head, or on some possibly plastic plastic part of the plumbing I've seen them on the intake manifold too.

where do you plan to measure this differential pressure

it will tell you different things depending on the state of the engine thermostat.

some engines are better designed than others.

What idiom and what description???

The intake manifold has water cooling? I've never seen that and I've never seen them anywhere other than major metal of the engine.

Before and after the water pump. My furnace has a humidifier with a differential pressure sensor to tell when the blower is running. It connects to both the hot and cold ducts. Works great!

The differential pressure may vary, but it will always be present while the engine is running... or I should say, while the water pump is pumping since that is what is measured.

Yeah, can't argue with that.

Rick C.

I have, and it's more about keeping the charge at a common sensible temperature. Not sure how effective it it.

Another technique is to use a hot spot from the exhaust.

Not so in my case. Temp shot up then back to normal, no lights or warnings . Coolant probably pumped out of the 1/2" hole. Pulled over and checked. Overflow tank still full. Several minutes later. Transmission oil all go ne, engine stall and check engine on. By that time, head gasket was done. No special effect (stream), as coolant was shooting out under the car. Most warning conditions only work for small leaks and higher up. Mine is t he worst case.

Actually, it is water heating, to allow better fuel vaporization during the first couple minutes after cold start. Most V8's and V6's have this, and a number of 4-cylinder engines have it, too.

As for fan belt breakage, a LOT of cars now run the coolant pump off the timing belt. This eliminates one possible cause of major engine damage, as breakage of the timing belt will immediately stop the engine.

Detecting loss of coolant under all possible circumstances has always been a tough problem. I know of plenty of people who had wrecked engines due to sudden leaks low down in the coolant system (bottom radiator tank in the days of vertical water flow), lower radiator hose, etc. while cruising on the highway, where all the steam went out under the car, and the temp sensor didn't pick up the overheat until there was major damage. I remember one guy who totally melted his engine. His first indication was a huge black cloud coming out the back, when he took his foot off the gas the engine seized.

Jon

manifold on the water circuit has been common for decades. It prevents icing.

NT

Most DOHC passenger car engines nowatimes are interference engines, if the timing belt breaks usually that's all she wrote for that engine.

"it does what it says on the tin."

measures coolant temperature, not engine temp.

Water heating, common in in-line carburetta engines with cross-flow heads..

Will tell you that the pump is running, will not tell you how much water is in there. - could be steam at the inlet to the pump and just a little water after it. the altenator lamp will tell you almost the same thing.

There's not much chance of your ducting losing all its air. so yeah it will work well in that application.

I had a water pump fail seized, the wheel sheared off and then the pistons bent the valves. imediately stopping the engine, took a bit of work to get that one going again.

When you run out of water the oil starts boiling, when you run out of oil it's game over. with luck you might get the oil warning before the engine seizes.

Yeah, we already discussed that.

If there is no water to be pumped, no pressure will register. Don't care if the water level is a bit low. Care about not enough water to cool the engine.

You aren't making sense.

Rick C.

What a load of crap. Overheating because of loss of water means you lose piston-to-bore clearance which are the parts which "seize" in the end. The oil stays where it is in the oil pan although it will end up warmer than usual.