I've been fiddling around this afternoon with a couple of digital gauges I picked up from Jaycar. I've mentioned them previously as I use one as a temperature probe by sticking underneath a radiator hose clamp and watching what the engine is up to. The gauges are panel mount, and are super accurate and very sensitive. Good for -50 to +150 ±0.05 deg C. They also have a high and low temp memory and alarm if you feel the need..
http://www.jaycar.com.au/productView.as ... rm=KEYWORD
Until now the gauge has generally just sat on the parcel tray, but as it was enjoying a semi-permanent status in the mini I decided I would mount it up and make it official. The idea would be that there would be no holes drilled, and that it could be hidden away when I didn't want it to be seen. I picked up a second gauge because I was keen on seeing what the oil temperature was up to as well...I can't help it, these things intrigue me....
These are the gauges, each gauge comes with a 900 mm lead (I wish it was a little longer...but they will do).
Using upholstery card I cut out a shape I figured would do the job, the idea is that the gauges would be mounted in the top and the bottom simply folded back to provide a base. A strip of Velcro will provide the anchorage.
Marked out the holes the gauges would pass through, the front is framed larger than the back to obscure the mounting holes.
I had two choices for the gauge temperature probe, put it under the radiator top hose, or slide it under the heater tap. For the time being I put it under the heater hose to keep the two wires running together, but will put it back to the top hose because it is simply neater to do so when installed.
Before you throw it in, coat the probe from the the base of the stainless steel to the back of the moulded plug with some epoxy. Then slide a piece of heat shrink over the top and shrink down before the epoxy has set. this will improve the protection of the probe from water ingress. Water will bring in a large temperature error if it gets into the cable.
The oil temperature probe is a tolerance fit into the fins of the oil cooler. I closed the fins immediately in front of the probe to keep the temperature a little more stable once air starts flowing over the oil cooler. As it is, the temperature will drop when the car moves forward and returns to the correct temperature once the car has stopped. This is the heat being drawn out of the oil cooler by the air blowing through it. It drops by about 20 degrees at speed.
I am without a Velcro tab at the moment, the plan is to sit it further into the background of the dash when it is mounted, but it will do sitting right where it is for the moment. I'll label the gauges correctly as well. The top gauge is oil temp, the bottom is water. This photo was taken tonight after a fairly spirited run around the back roads to get her nice and warm. Even so, the oil temperature is still only in the 70s while the water is in the 90s. The thermostat is a 90 degree unit, hence it keeps it a little warmer. The wires and covering MG black vinyl will be made a little neater in the morning... I am not a fan of my stock temperature sender, it's a little too sensitive sending the smiths gauge to the wall a little to early...
