Water level alarm

[Uncle Fester]

The thermostatic switch that originally controlled my fans is disused. First I replaced it with a Mod-Wise two stage kit, then with ECU control.

I was thinking about fitting a low coolant alarm. If the redundant fan switch were replaced with a level switch then I could use the existing boss for the new switch. It may not be the ideal location, but it's better than nothing and might save an engine.

So, what thread is the fan switch?

Does anyone know of a suitable level switch that's open when immersed, closed when dry?

I'm not trying to measure the level on any scale, just activate a warning buzzer/light.

Edited by Uncle Fester on Friday 5th June 20:36

[Loubaruch]

Is there any point? Surely if your coolant is low enough to cause possible engine damage the temperature guage would be wrapped round the back stop

[Guillotine]

Hi Fester.

yep, I've done this, tho not where you say.
A small float switch is in the expansion bottle and sounds a buzzer in the cabin when water level is dangerously low.

I was going to do a kit for this on monster but havn't got round to it yet. switch is s/steel, have to be careful which one you use as it is permanently immersed at over 90 degrees for long periods. Mine has been working for 5 yrs now.

Andy

BTW, if you have a water leak, the water disappears and the engine can be toast. the guage will stay at the last temp BEFORE the water goes...therefore you WILL blow your head gaskets probably requiring skims...new heads/engine???

[rigga]

Its an idea,but the switch position would need to be carefully thought out..... the expansion tank would have been of no use when i had a rad loose water over a long period of time,as the pipe from the expansion tank to the swirl pot was blocked,thin bore and it didnt take much build up to stop the coolant running back into the swirl pot as designed,i checked the level in the expansion tank every trip,and it was at the right level,didnt know the swirl pot level was getting low until the engine temp rose very dramaticly.... luckily was at my destination,so cooled down and the checked over and found the problem,as said you will know when you have low level by temp gauge indicating an unusual reading.

ETA this was the blockage on my expansion tank,i would advise checking yours at some point if the cooland hasnt been drained/changed for several years

Edited by rigga on Friday 5th June 23:12

Edited by rigga on Friday 5th June 23:13

[Uncle Fester]

Guillotine said:

Hi Fester.

yep, I've done this, tho not where you say.
A small float switch is in the expansion bottle and sounds a buzzer in the cabin when water level is dangerously low.

I was going to do a kit for this on monster but havn't got round to it yet. switch is s/steel, have to be careful which one you use as it is permanently immersed at over 90 degrees for long periods. Mine has been working for 5 yrs now.

Andy

BTW, if you have a water leak, the water disappears and the engine can be toast. the guage will stay at the last temp BEFORE the water goes...therefore you WILL blow your head gaskets probably requiring skims...new heads/engine???

Last year I lost an engine lost its water due to a slipped liner. On the bright side, it provided me with the excuse to justify fitting one of V8D’s finest to SWMBO. It’s left me a little cautious not to repeat the experience.

I have fitted an early type Ford temperature gauge sender (the correct type to match the gauge) into the original Rover sender thread with the use of a thread adaptor. I now have a gauge that responds immediately and is accurate throughout the scale.

I have an Emerald ECU. Mine is configured to ground a pin when the engine temperature reaches a (user configurable) pre set level. A buzzer is wired into this. Currently its trigger value is set to 95⁰C. With two independent ECU controlled fans coming on at different temperatures, I have never had the buzzer go off. This of course, is based upon the ECU temperature reading, taken from the ECU temperature sender. It provides me with a useful, independent confirmation of the gauge.

The idea of using the existing fan switch hole was a bit spur of the moment. The other thread on coolant loss set me thinking. As you say, temperature gauges don’t work well in warning of coolant loss. I was thinking as crude as wiring it from an ignition switched live and hooking into the car horn via an in-line fuse. It’s already all there at the front of the car anyway. If it did sound , then I could switch off, pull bonnet and pull the in-line fuse and check the water.

[Ant.]

[quote=Uncle Fester
I have an Emerald ECU. Mine is configured to ground a pin when the engine temperature reaches a (user configurable) pre set level. A buzzer is wired into this. Currently its trigger value is set to 95⁰C. With two independent ECU controlled fans coming on at different temperatures, I have never had the buzzer go off. This of course, is based upon the ECU temperature reading, taken from the ECU temperature sender. It provides me with a useful, independent confirmation of the gauge.


[/quote]

UF, how do you d this on the Emerald? I can see where the user output can be set up, but how do you then tell the ecu what you want to do with that selected output?

[Uncle Fester]

Here’s a screen grabbed from my map.



This is set to activate the buzzer at 95⁰C
For reasons I haven’t worked out, the buzzer also activates for about 10 seconds on first start up of the day from cold, but not on subsequent start up’s. I just treat this as a buzzer test.

You can also test the system by lowering the trigger values until the reach the current temperature.

I used a small buzzer that was originally bought from a motorbike shop. It was made to be fitted into the indicator circuit on a bike, so it beeped with the indicators. It’s loud enough to be heard over my Griff!