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Adding water temp gauge

21 July 2011
Westchester, NY
I'm looking to add an inline water temp gauge. I have an adapter that fits into a coolant hose and I'm looking for the best hose / place to tap into. There are 3 hoses leaving the engine to front radiator, two large and 1 small. I'm thinking the small one, which is 32mm, would be the best choice as I believe it's one of the upper radiator hoses. Am I correct? Always better to ask twice and cut once :cool:

See diagram attached.
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The little one goes to the heater core. If the heater valve is closed, you'll get the temperature of stagnant water so I don't think you want that.

If you don't have the Service Manual (SM), download a copy of it from Prime and look on page 5-14 for a schematic of the cooling system and how the lines run.

Just checked it, thanks for the info. looks like I need to tap into the larger hose that leads to the lower radiator. Does anyone know the diameter of the hose? I need to order a larger adapter.

Where did you tap into the hose, engine bay or front of car? Looks like it's a 38MM adapter.

Some will say you should tap it in the main lines under the TB but i'm performing logging/testing specifically on the efficiency of the rad so for me I placed one before and after the inlet/outlet of the rad under the front bonnet. It's much easier to access them up there too.

I suspect any temperature variance between the front or the back of car will be minimal if any.