The Ford Barn

billybronco1 · 07-27-2021, 06:18 PM

What would make the original temp gauge be maxed out all the time, never changes always red to the top? Can it be fixed or does everything from the engine to the dash have to be replaces and are the parts available someplace?

JSeery · 07-27-2021, 06:50 PM

An open circuit will show full hot. If it has the two senders, one in each head, one is an on-off switch. If it is off (open circuit) the gauge will show full hot. So would a disconnected wire.

ford38v8 · 07-27-2021, 09:16 PM

1939 has a mechanical temp gauge, no electrics in this one. It consists of a bulb in the head, a visible glass tube in the dash, and a small tube connecting the two, all filled with a heat sensitive liquid that is not available today due to being banned by the feds. The system is the most accurate of any type, but if damaged, as yours likely has been, lots of luck. Some guys say they are happy with repaired units, but I wouldn’t think a repaired unit could ever match the quality nor the longevity of an original, which are still available if you got the green.

mercman from oz · 07-27-2021, 11:49 PM

Ford Water Temperature Gauge.

chuck stevens · 07-28-2021, 06:53 AM

my 39 was that way after it was stored laying flat, during restoration. The mercury was separated by an air bubble. After years of driving I saw the air lock move up to the top of the gauge. I did nothing to make it move. The heat and cold cycles must have moved the bubble. It reads normal and is fairly accurate. I would drive it and keep an eye on your temp, good luck. 39's did not have electric gauges for temp.

billybronco1 · 07-28-2021, 10:13 AM

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I found it strange that is is pegged, If broken seems it would not register at all. Almost sounds like an air bubble has pushed to the max. I'm wondering if I try to cycle it hot and cold if I could get any change in it. Boil it freeze it type thing.

deuce lover · 07-28-2021, 10:21 AM

I have had them pegged before and that particular one was shot.Try freezing first.If it goes down you might get lucky.

JSeery · 07-28-2021, 01:48 PM

Quote:

Originally Posted by ford38v8

1939 has a mechanical temp gauge, no electrics in this one. It consists of a bulb in the head, a visible glass tube in the dash, and a small tube connecting the two, all filled with a heat sensitive liquid that is not available today due to being banned by the feds. The system is the most accurate of any type, but if damaged, as yours likely has been, lots of luck. Some guys say they are happy with repaired units, but I wouldn’t think a repaired unit could ever match the quality nor the longevity of an original, which are still available if you got the green.

Yes, I should know better! Same as the 38, I was thinking 40.

Juergen · 07-28-2021, 02:09 PM

First try boiling it in water with the gauge raised. The hope is the fluid will expand to be together. Next I have gotten some to get well by tying a string around the gauge and whirling the unit in a circle with the sender on the outside of the centrifuge. Do it for a few turns. I had one hanging down in the basement for 5 years before it freed up. And a NOS one wrapped in a coil in its original box which was still good.

ford38v8 · 07-28-2021, 07:33 PM

Quote:

Originally Posted by Juergen

First try boiling it in water with the gauge raised. The hope is the fluid will expand to be together. Next I have gotten some to get well by tying a string around the gauge and whirling the unit in a circle with the sender on the outside of the centrifuge. Do it for a few turns. I had one hanging down in the basement for 5 years before it freed up. And a NOS one wrapped in a coil in its original box which was still good.

The centrifugal force method should not be done with the unit unsupported. If attached solidly to a long pole, it can be spun round with no stress applied to the copper tube. I did this, which did prove successful finally, after suspending vertically with a vibratory on the sender tube for a week, which did nothing. The message is, air bubbles may develop anywhere the tube loops up then down, both in storage and in use on a car.

chuck stevens · 07-29-2021, 06:37 AM

If there is one thing to remember always keep the gauge higher than the bulb, and be careful of the tube, no kinks.

07-27-2021, 06:18 PM	#1
billybronco1 Senior Member Join Date: Dec 2012 Location: MA Posts: 570	1939 Ford tudor Temp gauage What would make the original temp gauge be maxed out all the time, never changes always red to the top? Can it be fixed or does everything from the engine to the dash have to be replaces and are the parts available someplace?

07-27-2021, 09:16 PM	#3
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,631	Re: 1939 Ford tudor Temp gauage 1939 has a mechanical temp gauge, no electrics in this one. It consists of a bulb in the head, a visible glass tube in the dash, and a small tube connecting the two, all filled with a heat sensitive liquid that is not available today due to being banned by the feds. The system is the most accurate of any type, but if damaged, as yours likely has been, lots of luck. Some guys say they are happy with repaired units, but I wouldn’t think a repaired unit could ever match the quality nor the longevity of an original, which are still available if you got the green. __________________ Alan

07-27-2021, 11:49 PM	#4
mercman from oz Senior Member Join Date: May 2012 Location: Queensland, Australia Posts: 10,333	Re: 1939 Ford tudor Temp gauage Ford Water Temperature Gauge.

07-28-2021, 06:53 AM	#5
chuck stevens Senior Member Join Date: May 2010 Location: upstate new york Posts: 758	Re: 1939 Ford tudor Temp gauage my 39 was that way after it was stored laying flat, during restoration. The mercury was separated by an air bubble. After years of driving I saw the air lock move up to the top of the gauge. I did nothing to make it move. The heat and cold cycles must have moved the bubble. It reads normal and is fairly accurate. I would drive it and keep an eye on your temp, good luck. 39's did not have electric gauges for temp.

07-28-2021, 10:13 AM	#6
billybronco1 Senior Member Join Date: Dec 2012 Location: MA Posts: 570	Re: 1939 Ford tudor Temp gauage Sponsored Links (Register now to hide all advertisements) I found it strange that is is pegged, If broken seems it would not register at all. Almost sounds like an air bubble has pushed to the max. I'm wondering if I try to cycle it hot and cold if I could get any change in it. Boil it freeze it type thing.

07-28-2021, 10:21 AM	#7
deuce lover Senior Member Join Date: May 2010 Location: Southern France Posts: 5,300	Re: 1939 Ford tudor Temp gauage I have had them pegged before and that particular one was shot.Try freezing first.If it goes down you might get lucky.

07-28-2021, 02:09 PM	#9
Juergen Senior Member Join Date: May 2010 Posts: 500	Re: 1939 Ford tudor Temp gauage First try boiling it in water with the gauge raised. The hope is the fluid will expand to be together. Next I have gotten some to get well by tying a string around the gauge and whirling the unit in a circle with the sender on the outside of the centrifuge. Do it for a few turns. I had one hanging down in the basement for 5 years before it freed up. And a NOS one wrapped in a coil in its original box which was still good.

07-29-2021, 06:37 AM	#11
chuck stevens Senior Member Join Date: May 2010 Location: upstate new york Posts: 758	Re: 1939 Ford tudor Temp gauage If there is one thing to remember always keep the gauge higher than the bulb, and be careful of the tube, no kinks.

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