Hello all, I am have a small issue with the installation of an aftermarket temp gauge on my 351m. I wish to retain the stock gague in addition to the aftrmarket unit. I know that i want to put the sensor in the water pump, and i know where the port is. The port is a 3/8" NPT fitting and so is the gauge sensor with no adapter. My problem is that the probe part of the sender goes into the hole and has nothing to sit against so that when i tighten the sender nut, the probe is still loose in the pump...Does this make sense? Do i need a special adapter to put it there? Please help!!

 

I installed an adapter in the top of the thermostat housing, just seemed a little easier for me. You'll need to get some brass fittings from the hardware store and make sure you have the fittings deep enough to accept the probe.

 

You don't want the temp probe sitting against anything, do you? Shouldn't it be in the coolant stream (that'll be there when you button it back up and have it running)?

I just put a new temp sending unit in mine this past weekend, and just screwed it in after taping the threads.

If that ain't right, please advise!

 

That's what I did and it's working fine.

 

You can install the mechanical probe in the side of the thermostat housing as well.That is where I placed mine.There should be some adapter fittings included with your new gauge.The adapters have a seat for the probe to set in and the compression nut on the probe tightens against the probe to complete the seal.

 

If you do this, won't the gauge be unable to read anything until the thermostat opens up?
If the thermostat sticks closed, this could be ugly....

 

It will give a better indication that the regulator is not opening.I gathered that the OP was wanting to keep his original gauge functioning.Installing the new gauge in the the water pump will not net much.Need to be able to read a block coolant temperature,or an outflow temperature from the block.

 

I too am running both. Main reason is it's a new engine and wanted a reliable mechanical gauge during breakin. Just haven't gotten around to removing it. I put it in thermostat housing also. Kit cam with enough adapters to seal up correctly. Nice thing is I can see when the thermostat opens. If thermostat fails, you'll see that immediately too. Always use a thermostat that fails to the open position. At least you can drive it till fixed with no damage.

 

I disagree with that statement, installing a temp sender in the water pump is exactly the
right thing to do because it's the water pump that circulates coolant through the block and
heater core even if the thermostat isn't open. The temperature of the coolant in the water
pump is going to be the same as that in the block.

 

And the water pump gets the coolant to circulate from where when the regulator is open and the system is at full flow?Still think that it is the same temperature as the outflow from the block?If it is,there IS going to be an overheating problem.I agree about the block water temp in bypass(cold),but not in full flow with the bypass blocked.

 

I still disagree with the assertion that a temperature sender installed in the water pump will not
yield much useful information, I have seen no evidence here to cause me to change my mind.

 

Personally I've never seen a place to install a sender in the water pump itself. Of course, I don't pretend to have seen all water pumps. "If" it was there, it would read temp of water circulating thru block until the thermostat opens. Then it would read the temp of water entering the pump from radiator, about a 40 degree difference if I remember correctly and radiator is cooling properly. But, I've been wrong before.

 

I use a place in the water pump where Ford put a VCV - temperature-actuated vacuum
control valve used for emissions stuff (EGR valve, etc.):





I installed an AutoMeter sender in there which is connected to an AutoMeter
temperature gauge on the dash and, in normal day-to-day city driving, the dash gauge
generally reads no higher or lower than the thermostat-opening temperature.

I trust this FAR more than I trust the factory gauge.

I figure if Ford uses this location to determine if the engine is warmed up, then it should
be adequate for a dash gauge sending unit.

There are two other VCVs mounted in the thermostat housing (gooseneck) but they
won't know anything until the thermostat opens.

However, good points have been made here, perhaps I'll switch the locations of the
two senders next time I'm in there for some reason.