8 replies to this topic

[sparkymae]

Hi. Is there a thermostat housing out there somewhere for a 1990 998cc Mini that will except a water temperature sending unit. Thanks.

[GraemeC]

These two:

https://www.minispar...-12g103-drilled

https://www.minispar...sing-early-cars

[Earley86]

I have been looking for one of these my self. I have the three dials in the centre one being water temp.

I have my normal sensor to the main clocks.

Looks like this could work for my centre dial.

[sparkymae]

Thanks GraemeC.

[Hpal]

I have drilled a standard one just recently, so it's doable. Drilled and tapped for 1/8" thread in the thicker part of the housing near the front, and on a bit of an angle so the temp sender clears the thermostat.

[Retro_10s]

These two:

https://www.minispar...-12g103-drilled

https://www.minispar...sing-early-cars

Is there a benefit to running a temp sender in the thermostat housing compared to the usual sender in the front of the cylinder head? is it a preferred method of reading temps, or is it simply another way to achieve the same thing?

[Ethel]

I'd say it's marginally better in the head. It'll be a bit more responsive on the engine side of the thermostat. More importantly, it's more likely to be in the coolant. Overheating often involves coolant loss & steam only holds half the heat liquid water does. If the sensor is above the water level it's liable to under read.  Where they're used it's usually for another purpose, like the vacuum valve on the emissions system. 

[timmy850]

The main reason those thermostat housings were introduced was the early Mk1 engines didn’t have the sensor port on the head. If you wanted to add a coolant temp gauge (that also wasn’t standard) you needed some kind of port to screw in the sending unit

I had mine on my Mk1 and it’d obviously read cold until the thermostat opened. This wasn’t really an issue as it was cold and not something to worry about. The amount of coolant being pumped through the system means it’s probably unlikely to get an air/steam pocket there when it’s running

[Ethel]

It'll usually make little difference, but I've found out  half empty cooling system doesn't register on the gauge the hard way.