R300 oil/water temp

[240Cup]

Another blat another anomaly...!

Have the combined oil/water temp guage which for most of the time was reading about 80 for both, but then suddenly one reading (I think it was for water temp but how do you tell?) was at 40 degrees, so pretty much right at the bottom of the range.

Thinking back this may have coincided with me hitting a god almighty pothole - no damage underneath but might a sensor have knocked off or something? Where are the sensors, presumably going into the block somewhere (technical numptie here...!)

Have checked levels oil and water and all seems in order, fan coming on at idle etc so seems to be an electrical glitch rather than something mechanical?

Cheers,

240

[Tango7]

240Cup said:

Have the combined oil/water temp guage which for most of the time was reading about 80 for both, but then suddenly one reading (I think it was for water temp but how do you tell?) was at 40 degrees, so pretty much right at the bottom of the range.

Thinking back this may have coincided with me hitting a god almighty pothole - no damage underneath but might a sensor have knocked off or something? Where are the sensors, presumably going into the block somewhere (technical numptie here...!)

Have checked levels oil and water and all seems in order, fan coming on at idle etc so seems to be an electrical glitch rather than something mechanical?

Cheers,

240

The sender units for both oil and water are the same. The water sender is in the water rail above the exhaust primaries (assume you have a k series). The oil sender will be in the anti-cavitation tank (aka Apollo tank) if its wet sump or dry sump bell housing if its dry sumped. They are a spade connector with a single wire attached in both instances.

To test the senders, switch the ignition on but don' start the car and touch each of the wires to earth. If the gauge works fine, the needle will deflect to maximum when you ground the wire. You will be able to prove which way the switch toggles too when you check the gauge.

If you do have to replace either of them, you don't have to drain the system down. With a cold engine, simply remove the old one, stick your finger over the hole and screw in the replacement. You shouldn't lose more a tiny amount of coolant or oil.

T

[Tango7]

BTW the other way to tell which way the switch works is the water temp always rises faster than the oil when you are driving the car from cold.

[grenpayne]

The senders are notoriously crap, so it's likely either a wire came loose off the spade connector as Tango7 says or the senders on it's way out. I always keep at least one spare in the garage as they seem to go on an annual basis!