Hi all, I bought a Mooneyes triple gauge set about two years ago- the coolant probe is mechanical and very large, surrounded by a 1/2 NPT male fitting. In the box there’s a variety of adapters with no stamping or description in the manual. This is being plumbed into a non-native Ford Cologne V6 which to my knowledge has an electrical sender that’s quite hard to reach. The plumbing is all custom and is outfitted with pretty large hoses, one of which is connected with a steel joint. As such I have purchased an aluminium inline hose adapter for a coolant sensor but the port is 1/8 NPT. A 1/2 to 1/8 NPT reducer will in all likelihood be too small internally to fit the oversized probe. I could always purchase a tap and thread it but in a pressurised system… would rather not. I also have an aluminium expansion tank plumbed in that has 9/16 18 ‘barb’ ports. I was again thinking of purchasing an adapter into this but it seems I can only find male to male adapters for these two threads. Does anyone own these gauges or dealt with similar? Very aware I could be missing something seriously obvious seeing as I can’t find any info on the web. Cheers!
Are you sensing temperature to see on a gauge or to operate an electric fan, etc? You mention 2 places in the cooling system which will operate at different temperatures. If you just want to read the temperature in the hose, get a brass plug to fit your inline hose adapter and then drill and tap it to take the sensor. I would rather use a threaded fitting than rely on a hose clamp in a pressurized system.
To see on a gauge, my blower fans are manual. Regarding the brass plug- what is the purpose? Is this to make the drilling through the pre-existing threaded hole easier? If it’s a 1/8 npt hole and plug won’t the drill bit just destroy the contents entirely? Or are you talking about plugging the 1/8npt hole and drilling elsewhere on the joint. Thanks again
Do you have a factory heater ? Do you need the factory heater , if not remove one nipple and use that port . Make sure the depth is correct and plug the other port . Most mechanical gauges are as you described. Be careful with the small tube that comes out of the sender .
You could screw in a 1/8th NPT male/male fitting into a bell reducer from 1/2 to 1/8th. The screw your probe 1/2 into it. Would add about 3/4-1 inch in length. Edit: the bell reducer would be female to female NPT.
The brass fittings that come with the gauge kit have the seat for the coolant probe to seat in. The threaded NPT male fitting just pushes the probe to seat into the brass fitting. So you need to drill and tap your in line hose adapter to fit the brass probe adaptor. Hope this made sense.
The fitting/seat for the mechanical sender is available in 3/8 NPT as well as a weld-in option. There are a few ways to do this for your car. If it was mine, I'd look at drilling and tapping the coolant line adapter to 3/8NPT and purchase the 3/8 fitting from a gauge vendor. Example: https://www.pegasusautoracing.com/productdetails.asp?RecID=8783
Here is the solution I devised if anybody in future faces a similar issue: Inline hose adapter with 1/8NPT port. 1/8NPT male to 1/8NPT male. 1/8NPT female to 1/2NPT male. 1/2 NPT female to 1/2NPT female coupler union. Convoluted but suits my purpose perfectly. Brass adapter is 1/2NPT adapter supplied with kit.
I used a thermostat housing spacer for a heater hose connection, additionally I drilled and tapped another port for the electric fan, this way both the guage and the fan "see" hot coolant before the radiator. You can use just the large port for your guage, it is 1/2 npt, Pic shows the spacer ports are on the backside.
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