Temperature Gauge rising

[gwentman]

Hi I have a chimaera 450, can anyone help please? as soon as I start up the engine, the temperature gauge rises to maximum, I have recently had the radiator re cored, but all was working perfect.

Thanks in anticipation

[phazed]

looks like you may have a faulty otter switch if the gauge instantly goes to max.

Located at the base of the swirl pot on yours I think.

[BIG DUNC]

If you have just had a new rad I would check there is no air in the system.

After filling my system, the car would overheat after about five mins of eng running. It had all the symptons of a thermostat, only a new thermostat didn't cure it. There was, however, an airlock meaning that there was no water at the water pump.

I am not sure of the exact set up on Chim, but can you remove the top hose from the swirl pot and pour water into the thermostat / water pump from there?

[Classic Chim]

Sounds like an electrical fault ( to clarify )
Does the gauge instantly go up within a few seconds or related to engine warming up?

Otto switch, if it’s not situated on the swirl pot it might be a later car in which case it will be situated on the left hand side of radiator with two wires plugged into it.

[BIG DUNC]

If, by "instantly" he means within ten seconds of starting the engine it as overheated, then definitely electrical.

The otto switch just turns the fans on and off, so I wouldn't describe that as causing a problem immediately the engine is started.

I was really surprised how quickly mine overheated when it was air locked. I live at the end of a short cul-de-sac. Just driving to the bottom of the road and back and the temperature gauge was higher than it should have been. Top hose was cold hence suspecting it was the thermostat initially in my case.

As he has just changed the rad, the water could well have drained out the water pump, hence why it is definitely something to check early on.

[Penelope Stopit]

gwentman said:

Hi I have a chimaera 450, can anyone help please? as soon as I start up the engine, the temperature gauge rises to maximum, I have recently had the radiator re cored, but all was working perfect.

Thanks in anticipation

This is definitely an electrical fault due to it happening as soon as you start up the engine. A cold engine with no water will still take some time to warm up and no water = temperature sensor under-reading

[Steve_D]

First test is to see what the gauge does when you turn on the ignition but don't start the engine.
Many gauges go full scale deflection when the sensor is disconnected.

Steve

[gwentman]

Hi Thanks for your replies, the temperature gauge goes up when you imediately start the engine

[BIG DUNC]

Just for the avoidance of doubt, what about ignition on, engine off?

& when you say immediately after you start the engine, do you mean in 1 second, 10 seconds, 1 minute, 4 minutes.....

[gwentman]

update, I just tried ignition on, and engine off. The gauge goes up to maximum.

[bobfather]

gwentman said:

update, I just tried ignition on, and engine off. The gauge goes up to maximum.

Wire may have come off the sensor.

[Hedgehopper]

To test a gauge you short the wire to earth and this will give a maximum reading. Same goes for fuel or oil gauges. Therefore somewhere your sensor to gauge wire is earthing itself.

Edited by Hedgehopper on Tuesday 29th January 10:50

[gwentman]

Thanks for all your replies, I will look at the sensor wires.

[QBee]

Panic over

[gwentman]

Fault found changed the coolant sensor gauge, now all good, thanks again for all the input.