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I have had a radiator go on me recently and it occured to me that I didnt notice the Temp guage until there was steam spewing from under my bonnet.

Infact.... I dont think I ever look at my temp guage at all.... ever.

So.... I am need of some sort of High Temp Alarm of some sort...

Whether it be a un-ignorable flashing light or my prefered option gentle but also unignorable audible alarm. Getting hold of a Jaycar kit wont be a prob but getting to go off at say 75% of max gauge temp is another thing. I'm guessing the temp guage works on a voltage of some sort so if that can be sourced and used to trigger some sort of relay then maybe it can be done. And it would also need a reset switch of some sort.....

I have a basic idea but wonder if anyone knows of a sure fire way to get this done...

Cheers

and there may be two conditions to consider to monitor, water temp and engine temp. The thermistor gives a reading to gauge or ECU of water temp but its shortfall is if suddenly all water is dumped there is then no water or only steam in the block and the usual water temp sensor do not sense steam temp and gauge loooks normal. monitor engine temp may be too late. VDO now do pressure switches of various ratings up to 100 psi and slightly adjustable. That would be interesting if you could do a low pressure alarm switch on coolant chamber, if you can avoid initial start up of low pressure, almost need a no presure alert to cut in after a warm up period.

As steptoe said - the temp guage won't read the temp of steam... The other way around this is to monitor engine oil temp. If the coolant is dumped the oil will absorb the rising tempreture and this will be shown through the oil temp - probabily a more reliable place to sort out an alarm...

Cheers

Bennie

http://www.fullwavemarine.com/tempgauge.html

Aftermarket is the easiest way IMO, and one of these is a great little unit and simple as.

i was almost gonna get one but already had an aftermarket guage and sender and adaptor so just transferred that from the Subi to my new car and has been fine.

a low water alarm would be a good start. every time i've had an engine get too hot was because it had low water.

just like used in Falcons for last twenty years, all sixes had same sort of reservoir but not all had low water alarm. my brain is still thinking of L series EA application, dunno if it would work with overflow bottle of L Series, though I have tested a car that was losing water and was drawing on reservoir while driving- against all theory i had learned.


That is a good simple little add on. price ?? 149 bucks delivered would be half a good distance tow job , soon to scour the net for cheaper deal....

I think you'll find that those Foulcans pressurise that "bubblepack" reservoir as in the pressure cap is on it rather than the radiator tank .

The L reservoir is really just an overflow recovery reservoir , its downstream of the rad caps outlet so not pressurised .

What you can do is make an inline joiner in your top hose and fit the sensor in there , the highest point in an NA EA82 cooling system that is pressurised is the top hose (turbos it's the turbo coolant return pipe) but its impracticle to tap in here .

A .

I am not that far from picking up the phone to order meself one of the above TM2 engine watchdog. It has easy hook up as in cig lighter if you care and the sensor bolts to block or thermostat housing, digital display, adjustable alarm and the mounting point des not interfere with coolant integrity.Also can alert to overheating due to oil loss if that makes engine hotter and can hook up to oil pressure switch light to sound alarm if you don't see the idiot light on dash.

steptoe wrote:I am not that far from picking up the phone to order meself one of the above TM2 engine watchdog. It has easy hook up as in cig lighter if you care and the sensor bolts to block or thermostat housing, digital display, adjustable alarm and the mounting point des not interfere with coolant integrity.Also can alert to overheating due to oil loss if that makes engine hotter and can hook up to oil pressure switch light to sound alarm if you don't see the idiot light on dash.

Yep, id say go for it.

they did use to be around $100 but have gone up like alot of things in our world recently.

i got the link off one other forum particularily (but have seen it mentioned on a couple) where alot of people are using the sensor and love it.

(not affiliated with them in any way either)

Got one of the enginewatchdog.com TM2 off the signals people. It is a neat unit. I just removed thermostat bolt to fit lug underneath, plugged the cig lighter plug in as supplied and away I went. Unit sits where the front hash tray was and can't see unit in 5th gear. At normal op temp it reads 70 degrees. I set screamer to go off at 85. Can come back after ten minutes of engine off and heat soak has an effect of getting sensor hotter so on start up it screams until cooler again - 30 seconds or so. It has large red LED readout so even the back seat pax can read it - maybe even the car behind you! I like the fact it comes with an extra wire to hook up to an oil presure light switch to sound buzzer so you don't need to be on the lok out for oil light on dash anymore.

Personal choice but I'd set it to somewhere in the 90's and even that temp won't tickle the engines tummy .
What kills heads and gaskets is usually uneven temperatures because thats what causes uneven expansion rates .
If you want to play around with things possibly mounting your sensor eye somewhere on the head casting may give a more significant indication of imminent doom .
I just keep thinking that if your donk dumped its coolant quickly the temperature may not rise quickly enough in that thermostat housing for you to shut down before the damage was done .

I was actually wondering how it would go on one of the "spare" exhaust outlet header bolt holes .
Cylinder heads always get the most rapid temperature rise near exhaust ports/valve seats when the water cooling system fails .

Cheers A .

Working on the temp mark for alarm, so far 85 is good most occasions. The makers suggest rocker cover or thermostat housing but I guess that has different positions on different engines eh - look at EJ V EA! The max temp of alarm is 127 C. From memory suggestion is to keep away from exhaust esp for sensor wire ! You are right it is all experimental and it is the heads that do the cracking and close to where the heat is created. The packing also indicates or detects coolant loss, blocked rads, t stat fail, WP fail, broken belts, air flow restrictions, oil system fails. All peace of mind stuff and is interesting to see although water temp comes up to normal within minutes I noticed last night it took considerably longer for engine temp to show its normal 71 deg C - about 6 mins 6 kms.

I don't have time to look ATM but are there support brackets on the drivers side head for turb oil/lower coolant line ?
Low on head casting but away from exhaust is probably a good compromise , would heat up real quick with little or no cooling water present inside .

A .

I am new to this forum, but not to this problem.
The problem with gauges is that unless you watch them all the time, or can scan them every 30 seconds, you will normally not see any warning indications before things go wrong. Thats just a fact of having to keep your eyes open and focused on the potholed, speed limit change every 10 metres, school zone every 20 metres roads and the many morons we share the roads with.

A noise maker is not a good system, they can distract you too easily at the wrong moment, or scare the person that borrowed your car into a crash , or worse, wake the the baby that has finally gone to sleep after screaming in your ears for the last 100kms!

A warning light is best. Aircraft use them for just this reason. Military aircraft use a a master caustion light, a system warning light, and then a gauge or indicator. If things go bad you get both lights on to tell you to look at the gauge.
I would suggest you use a warning light system that is triggered by a no water in the header tank sensor. Silicon Chip did a circuit for one of these a few years back. A warning light driven by a temp sensor switch strapped to a radiator hose would also work.
Try this for a simple system. It worked on my old Camry.
1 x Jaycar switch - cat # ST-3836
1 x Jaycar warning light - Cat # SL2644 This is an LED type, so make sure you wire it up the right way around!)
1x fuse holder - cat # SZ-2015
1 x 1A fuse - cat# SF-2189
And of course, some wire. Small gauge stuff is fine, what the car shops sell as 7.5A rated is more than adequate.
If you want to be fancy, add in a 'press to test' switch - cat # SP-0732

Mount the warning light where it will grab your attention, but not be directly in your line of sight, or be normally washed out by sun light. A switch hole cover plate is often a good place, and easily replaced if you decide on a something different later. If you have decided to fit the press to test switch, mount it under the light on the same plate.

Connect one side of the fuse holder to the +ve side of your cigarette holder.
Connect the other end of the fuse holder to the +ve side of the warning light.
Put the fuse in the holder.
Connect a wire to the negative side of the light and run the wire out into the engine bay. Make sure you take the wire through a grommeted hole in the fire wall. Next to the accelerator or clutch cable is usually easy to get to.
If you have installed the press to test switch, also connect one side of the switch to the negative side of the warning light.

Fit the temp switch to the top radiator tank or radiator hose. for the tank, initially use super glue to hold it in place. On a radiator hose, a Jubilee clamp will work fine, just dont squash the hose by doing the clamp up too tight.

Run the wire from the light along side the main wiring looms and cable tie the wire neatly every 6 -8" all the way around to the radiator/radiator hose.
Connect the wire from the negative side of the light to one side of the temp switch.
Connect the other side of the switch to a ground point ( any screw or bolt that goes into the main body of the car is fine)

On the press to test switch, connect the other side of the switch to a ground point. It does not have to be the same ground point as the temp switch.

And thats it. Once done, turn the ignition switch on ( dont start the car)press the test switch and the warning light should come on.

To finally fix the temp switch in place - dont use screws! If you cant make up a bracket for the tank fitting then use 'gap filler' foam over the sensor- being careful to only use a bit- it goes a long way very quickly and damages paint even quicker. If you use too much foam, it can be carefully carved back and painted once it has set. The foam will act as a locater and a glue.

Now, when ever that point you have that temp switch on gets to 100C, the warning light will come on. Your water will be a bit hotter than that - by up to 10 deg C. And if your radiator is running at 110 Deg C, its time to slow things down, watch the temp gauge and maybe look for some where safe to pull over and check things out.

ozzyeureka wrote:I am new to this forum, but not to this problem. ........

Thx for a great solution mate.

Matatak wrote: i was almost gonna get one but already had an aftermarket guage and sender and adaptor....

Can you tell me a little about that...???

I've installed a Watchdog in a number of places and its really not that accurate IMHO. I have tried centre of the block, thermostat housing bolt, injector rail mounting bolt. Nothing gives an accurate temp compared to the ECU recieved ECT via laptop.....

Here was my solution, I bought the low water sensor from a Falcon ($47) and modded a turbo header tank for it to fit (both my cars are turbo) unfortunately we couldn't work out how to power it, 12v= no good, relay= no good, LED light I think sort of worked so the idea was good but that's as far as it got...........I MUST finish it as I've already lost one motor because of a snapped hose.
We (the auto sparky & I) cut the plug off and tried most things to no avail, I guess it could be adapted to a radiator or overflow bottle if you could work out how it worked...looks simple but?????

The unit, as you can see once the float drops it bridges the power....if you can work that bit out lol,




Filed flat ready for drilling


Drilled


Cap which was later drilled to hold it in place.




You can see how it would work on low water

isnt that just a float switch? bit scary if your "auto elec" couldn't wire it up..