Temperature sending unit "Difference"??

rockfla

Well-known member
Pulled this temp sending unit out of the head while (Pic #1 and #2) replacing head gaskets and figured while its off I'll go ahead and put a new one in. Got a new one (Pic#3) and its different, two lugs, one short, one long, both with machine screws........Why two lugs and now my temp gauge is pegged "H" before I even start the car. Suggestions
 

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Yip, you have the wrong part for the variable sender. The single is the variable unit, the two terminal is an on/off switch.
 

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Speaking of this I have a 1950 F1 with a V8. My gauge did work but has since stopped is there a good quality source to replace the sending units?
 
The word on the street is that replacement sensors are available, but they are of questionable quality. Your best option is to find a good used working sensor. In the alternative, these can be repaired. The hardest part is getting them apart. I did one a few years ago. Check out post 5-11 in this thread : https://www.fordbarn.com/forum/showthread.php?t=226078.
 
The word on the street is that replacement sensors are available, but they are of questionable quality. Your best option is to find a good used working sensor. In the alternative, these can be repaired. The hardest part is getting them apart. I did one a few years ago. Check out post 5-11 in this thread : https://www.fordbarn.com/forum/showthread.php?t=226078.
The "old" one was working when I pulled it out. I had to grind the head off the round head machine screw as someone walloed the straight slot out and I could not get it loose, then the body off the screw was a little tight getting it out. When I was ordering a few odds and ends I had Mike throw in a new temp sending unit thinking I would just go ahead and put a new one in. NOW got the body of the old one out last night and got a new brass screw from here at work and will re-install the "old" one back tonight when I get home.
 
My information about the quality of aftermarket replacements is admittedly several years old. If Mike is carrying them now, I'm sure they're OK. That being said, good original parts are best.
 
I for one agree on the NOS parts. They are worth the price knowing 9.9 out of 10 they are going to work without trouble.
Though I'll also say, buying newer parts from those that truly care and keep an eye on things like Third Gen., and VanPelts to name just a couple means a LOT, too.
 
Rockfla,
I appears we sent you the WRONG switch, the fault lies in our end...
We have the "correct ones" and likely one was pulled from the wrong bin. Feel free to return that one and I'll cover the return postage.
 
Rockfla,
I appears we sent you the WRONG switch, the fault lies in our end...
We have the "correct ones" and likely one was pulled from the wrong bin. Feel free to return that one and I'll cover the return postage.
Mike
It's okay, Ill keep it as there are many more flatheads coming down the line and I "may" find I need it. IF not I'll have one in case someone else may happen by and need it. As stated above, the old one still works and a little extra time spent last night and a new screw from work today had is ready to be reinstalled tonight so NO WORRIES. AND once again thanks for all your help.
 
Aftermarket ones are not very good, the originals rarely go bad (unless broken). I bought good used and nos ones only.
 
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