Adding temp probe and temp gauge

   / Adding temp probe and temp gauge #1  

Scotty Dive

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Feb 5, 2010
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Location
Ct
Tractor
Yanmar 2020D
I am still gathering the parts to add gauges to my 2020D. I want to add a temp gauge while keeping the stock temp warning light.

The idea was to cut into the top radiator hose and install an adaptor that will allow the temp probe but I cannot find one that will work. Like this: Radiator hose adaptor-Prosport Gauges Upper radiator hose adaptor

So I was thinking of making my own...do you think using regular steel tubing would hold up and not rust? I was thinking of getting a 2-3 inch length of 1 1/4 OD pipe. Cut a hole on the side and weld a 5/8 nut that will allow me to bolt the temp probe on to it and in the water flow. I can then use hose clamps to hold it in place. I thought I could also run a bead around the cut ends of the pipe and then grind it smooth to mimic the flared ends usually found on the ends of radiator pipe.

Thoughts?
 
   / Adding temp probe and temp gauge #2  
Why won't the adapters in your link work? They're available to fit hose with 1 1/4" inside diameters. Is it your temperature probe thread size/pitch? What about getting a new temperature probe?

Having said that, I don't see why it wouldn't work to use regular steel tubing. The inside of engine blocks are bare cast iron. If you're worried about it, just spray paint it. :D
 
   / Adding temp probe and temp gauge #3  
fwtw I recently took my light sender out and am just using the gage now I was using the stock location where the sender was in and tee'd the gage and light together.

I found the gage wasn't sensitive enough and went straight into the stock hole with it ymmv as always but thats what I discovered. Brass or stainless is the best materials in a cooling system those adapters look like they would do fine as long as there is enough hose.
 
   / Adding temp probe and temp gauge
  • Thread Starter
#4  
the probe attaches using 5/8" and these adaptors are 1/8" npt. I bought all three gauges in a package and would have to source something from scratch. I could take that adaptor and have it re tapped to 5/8 but I was thinking I am over thinking this.

I was thinking of using copper and soldering in the nut but wondered if it would be strong enough to handle the vibration.

The stock light is electrical and the after market guage is mechanical
 
   / Adding temp probe and temp gauge #5  
The last gauge I bought and installed was into a jet boat, and it was this one. It came with adapters. The adapters are a Sunpro part, though, and available as a stand-alone item.
 
   / Adding temp probe and temp gauge
  • Thread Starter
#6  
That one is electrical ...the one I have is mechanical and does not come in 1/8 npt :(
 
   / Adding temp probe and temp gauge #7  
the probe attaches using 5/8" and these adaptors are 1/8" npt.

Looks like to me there is enough meat in the adapters to simply drill out to the 1/4" npt or 3/8" npt whatever your gages came with.

I am guessing your gage has a nut on the end of the line behind a probe that goes to the gage and this nut screws into an adapter they supplied that screws into the block yes?

I may be wrong about it working its hard to tell for sure in a picture but aluminum will drill and tap real easily thats for sure.

My temp gage is electric and it does use an 1/8 npt sender much much easier to install imho btw.
 
   / Adding temp probe and temp gauge
  • Thread Starter
#8  
I know someone on this forum built there own to accomplish this - I hope they chime in.

I took some 1" ID galvanized pipe and welded a 5/8 nut to it but two issues became apparent. First the probe is about 1 1/4" so it bottoms out inside the tube. I could weld another nut on top of it to solve that problem. The more concerning issue is that the homemade adaptor is heavy. I don't think a cut radiator hose would be able to support the extra weight.
IMAG0099.jpg

With the aluminum manufactured version - I think I will run into the same issue with the probe bottoming out and with it being aluminum, I can't weld anything else to it....so I would have to bring it to a machine shop and that is $$$

I have a call into my Brother in law who is a plumber to ask him if I can make this out of copper and silver solder a couple of metal nuts to copper and if he thinks it would be strong enough to hold up.
 
   / Adding temp probe and temp gauge #9  
You could solder/weld it at an angle.
 
   / Adding temp probe and temp gauge #10  
Is that a galvanized pipe fitting, or something like fence pipe? If it's fairly thin wall, I don't think the radiator hose will have any trouble once it is attached securely on both ends. I don't see anything wrong with welding another nut onto it, but I would suggest drilling out the threads on the first nut.

It's tough to make threads line up perfectly with the heat of welding and cooling, and your probe's threads will be mangled when you try to install it, I think. Just drill the nut out out, then weld the next one so it fits.
 
 
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