Coolant sensor AULRO order- question

[DeeJay]

I once nearly siezed a V8 rover motor due to a siezed - in the closed position- thermostat.
From memory I checked the radiator and hoses ( the dash temp guage was in the red) and they were cold as a frog, so I put it down as an electrical fault, but after a second check, the motor was red hot.
Effectively the thermostat was preventing the radiator coolant getting to the motor.

My question is-- would the top radiator hose sender on this unit also fail to detect a jammed thermostat as the coolant never even gets to the motor. ???

[97discotdi]

The thermostat doesn't stop the water getting to the motor. the water pump draws the water from the bottom of the radiator and returns it to the top of the radiator.

[CraigE]

V8s are a little different to diesels. A thermostat on a v8 petrol may stop water flow to the block and cause overheating. The engine water temp is on the block side of these so always take notice of temp readings and find out why. I have seen them stick but not completely seize. The point of the thermostat is it stays in the closed position until the coolant in the block heats up to a given temp and then should open. You can run a v8 petrol for short periods with the therostat removed. Quite a few older holdens and fords used to have them removed completely in hot areas of Australia by owners.

[DEFENDERZOOK]

removing the thermostat may not always keep the engine running cool......

without the thermostat.....there is no restriction in the coolant flow.....
this will allow the coolant to flow through the system too freely....
which means it wont be in the radiator long enough to cool down.......

[rick130]

short answer, no.
Low coolant sensor wont activate if the t/stat remains closed, as there is still coolant in the top hose as a water pump impeller isn't a positive displacement device (whereas a piston pump is)

[jessie_xa]

DeeJay,


As the per below, it only sensor's the level of the coolant not the temp so it will not tell you that the thermo is closed or open.


An Engine Saver® is a device which monitors the coolant level in an engine.
Low coolant alarms are fitted to very few engines as standard equipment by manufacturers. If the coolant level drops due to a split hose, a stone through the radiator, a faulty pump seal or simply because the radiator cap wasn't replaced properly this device is designed to warn you. Before any engine damage is done

The job of the thermo is to hold the water/coolant in the motor, once the fluid is at the correct temp the thermo opens allowing the coolant it to flow OUT via the top hose to the radiator. there is NO restriction of coolant flow to the motor via the bottom hose


Effectively the thermostat was preventing the radiator coolant getting to the motor

[LandyAndy]

The coolant sensor detects a lack of water and a buzzer sounds.
I always drill a 1/4" hole in the face of the thermostat.It helps with bleeding and it prevents an air pocket stopping the thermostat from reading the real water temp.
Andrew

[chazza]

A Mazda van I once owned had a coolant level sensor - it saved me a new engine when I first bought it (leaking water pump), which is why I have ordered one for the Disco.

Really worth having and I can keep it when I sell the car!:D