Radiator temp sensor

[tjbrookes2004]

Hi , I've recently purchased a new radiator and the 4 main hoses , I've also decided to put an inline water temp sensor and gauge , my query is which hose should I put it on , im thinking of the top radiator hose , I already have the low coolant alarm connected, im just being super cautious lol

[g8dhe]

What do you expect the radiator temperature to tell you precisely ?
There is coolant flow thru other parts of the cooling circuit as well as the radiator which only comes in to play when the thermostat opens to allow cool coolant to add to the flow.

[oibaf]

No doubt your engine will appreciate the new bits and pieces. I'd be more inclined to put the temp sensor at the back of the engine though. There are a couple of spare holes there that you can tap out to fit the sensor. It's where people put the likes of TM2 engine temp alarm sensors and such. That will give you an indication as to what the head temp is and can compare values with other Bongos so you're not fighting blind so to speak.

[teenmal]

Yes the top radiator hose is the way to go,I have fitted a few ...perfect.

[Hazzobongo]

What do you expect the radiator temperature to tell you precisely ?
There is coolant flow thru other parts of the cooling circuit as well as the radiator which only comes in to play when the thermostat opens to allow cool coolant to add to the flow.

Thermostat will open at 82deg and will stay open while you continue driving just like every other car the engine is designed to run at this temp and the temp should only increase when the engine is under load like going up steep hills or towing and should pose no problem with a well maintained system so fitting a temp guage in that top hose will at least tell you that the heat is building up in the engine which is better than the dash guage as at least if its heading higher than 110 or so deg you can pull in and let the system cool down.

I fitted one to my hilux surf after the head on that cracked after hauling a three ton loaded trailer so that I knew the real water temp rather than rely on a guage which only indicates when you're having a disaster.

On the surf the auto tranny cooling was what caused the problem as it passed through a lower chamber of the radiator to be cooled, it just wasn't sufficient or efficient enough and needed an oil cooler which I plumbed in following that disaster too and had no more issues, how is the auto trans on these cooled? H

[oibaf]

Sounds like a good plan based on your prior experience so. Any extra warning is better than none really!

I'm not sure where the ATF is cooled but if you follow the pipes under the gearbox it should be easy to see. I think there might a cooler matrix for it which is separate to the main rad.

[g8dhe]

The ATF is cooled in a separate section of the radiator at the bottom, it has its own connections etc at the bottom.

[teenmal]

What do you expect the radiator temperature to tell you precisely ?
There is coolant flow thru other parts of the cooling circuit as well as the radiator which only comes in to play when the thermostat opens to allow cool coolant to add to the flow.

Thermostat will open at 82deg and will stay open while you continue driving just like every other car the engine is designed to run at this temp and the temp should only increase when the engine is under load like going up steep hills or towing and should pose no problem with a well maintained system so fitting a temp guage in that top hose will at least tell you that the heat is building up in the engine which is better than the dash guage as at least if its heading higher than 110 or so deg you can pull in and let the system cool down.

I fitted one to my hilux surf after the head on that cracked after hauling a three ton loaded trailer so that I knew the real water temp rather than rely on a guage which only indicates when you're having a disaster.

On the surf the auto tranny cooling was what caused the problem as it passed through a lower chamber of the radiator to be cooled, it just wasn't sufficient or efficient enough and needed an oil cooler which I plumbed in following that disaster too and had no more issues, how is the auto trans on these cooled? H

The cooler is built into the rad, there is a wee difference re thermostats , the wltd is fitted on the return side of the flow which means it is getting hit with cooled coolant and will tend to open and close more often than the normal stat position. It will be like a fiddlers elbow .

[Hazzobongo]

What do you expect the radiator temperature to tell you precisely ?
There is coolant flow thru other parts of the cooling circuit as well as the radiator which only comes in to play when the thermostat opens to allow cool coolant to add to the flow.

Thermostat will open at 82deg and will stay open while you continue driving just like every other car the engine is designed to run at this temp and the temp should only increase when the engine is under load like going up steep hills or towing and should pose no problem with a well maintained system so fitting a temp guage in that top hose will at least tell you that the heat is building up in the engine which is better than the dash guage as at least if its heading higher than 110 or so deg you can pull in and let the system cool down.

I fitted one to my hilux surf after the head on that cracked after hauling a three ton loaded trailer so that I knew the real water temp rather than rely on a guage which only indicates when you're having a disaster.

On the surf the auto tranny cooling was what caused the problem as it passed through a lower chamber of the radiator to be cooled, it just wasn't sufficient or efficient enough and needed an oil cooler which I plumbed in following that disaster too and had no more issues, how is the auto trans on these cooled? H

The cooler is built into the rad, there is a wee difference re thermostats , the wltd is fitted on the return side of the flow which means it is getting hit with cooled coolant and will tend to open and close more often than the normal stat position. It will be like a fiddlers elbow .

If thats the case then I don't understand the need to empty and refill ATF through the dipstick, on the surf I put a hose from the ATF cooler intake pipe into a bucket and the return to the tranny into a five litre container of ATF (the one it comes in) then fired up the engine, it sucked the good stuff in and ejected the old into the bucket, once it started flowing red again switch off the engine and reconnect the pipes/hoses.

On the stat point are you certain this is the case, really odd, I like the fiddlers elbow comment

[Hazzobongo]

The ATF is cooled in a separate section of the radiator at the bottom, it has its own connections etc at the bottom.

Cheers for that Geoff I got underneath the front today but couldn't see where they were, I need some ramps to get this thing up high enough to get my old fat aris in there.

I'm having the Timing belt done on tuesday and plan on going right over the coolant system, tranny and underseal as the weather warms up, I was doing the belt myself but the Mrs persuaded me not to due to the tight squeeze, cant use jacks or axle stands as the drive is a slope and the street is on a hill, I've got nee luck.

I changed the oil yesterday in a car park but only with a pump extractor and just to get some fresh into the system as the PO never bothered in 6k miles and he was the first importer, by the looks of the stuff which came out I reckon it got its last change in Japan over three years back so I'll be flushing it next time around.