Ok boys and girls, this has been a burr in my side for a little while now but I think I've got this licked. Most '56 owners know that Ford, in their infinate wisdom upon the switch to 12v, left the gauges as 12v units aswell. Some of you, like me, desire the want to run 'as original' gauges in their rig but cannot get (or afford) the 12v '56 only' sending unit or get it to work in a more modern engine. Well folks, I'm here to tell you I believe i have a low-cost solution to this problem.
Thanks to my father and his ability to re-invent the wheel and do it cheaply, he shared with me this little swap of his. Problem was, he could not remember what year of rig he was stealing parts from. (He'd last done this back in the 70s and described the donor truck as 'somewhat late model' at that time and said they were plentiful in the junkyards aswell. With some picture research and note comparing I think i keyed in on his donors.
Ok here we go-
I sourced a used '57-'60 pickup temp gauge (which came with a fuel gauge and voltage reducer too) from a buddy of mine for free. These gauges differ as Ford stepped back to 6v in '57 and changed the functionality of the temperature sender. This temp sender (as it appears in pictures and by description) is smaller and shorter by far than the '56's sending unit. Because of the large size (mainly length) the '56 sending unit will not work in more modern engines, is usually too long and will bottom out in most intake manifolds before even getting to the threads. The '57-'60 sending unit appears to be MUCH smaller thus making it able to be installed into most intake manifolds of more modern engines. I need to confirm this for sure (haven't actually bought one yet) but from what I've seen in pictures and descriptions, it's a winner. And to top it off, this sending unit is very easy to source and MUCH cheaper than a '56 unit. Of course you WILL need to run a voltage reducer on just this gauge as it is solely designed for 6v operation. No problem, as the stock reducer is available, as well as aftermarket versions too.
Ok here is the rundown on making the '57-'60 gauge work for the '56 dash.
Here is the two gauges. The '56 gauge on the left, a broken unit from a spare dash and the donor '57-'60 gauge. I know it's cruddy looking and the needle will need re-painting but I'll do that later on. Luckily the '57-'60 gauge tested good, so that was a huge score!
Again, back sides of each gauge. The important thing here is that the main gauge housings are EXACTLY the same. The faces and rear mounting flanges are all that is different, and are easily removable.
Here i have disassembled the '56 gauge. You'll need to be gentle removing the face of either gauge as not to disturb the needle. Save the '56 gauge face and the rear mounting plate. The face will pop off easily as it as 3 pinched areas on the edge. The rear mounting plate is retained by the two nuts on the back.
i disassembled the '57-'60 gauge in the same fashion. Using the main gauge body of the '57-'60 gauge i reinstalled the face and the rear mounting plate of the '56 gauge. I didn't repaint the needle just to show you that it is infact the '57-'60 gauge i put the '56 pieces on.
As you can see here, it appears in all fashion just as if it were a '56 gauge. The rear mounting plate and face fit like they were meant to be there.
Here is the newly re-fitted gauge installed into one of my spare dashes. Fits just like it should.
Here i included the factory '57-'60 voltage reducer just so that you'd see what it looks like.
Here's the backside of the '56 gauge with the mounting plate removed. You'll see a couple open holes on the backside with little teeth visable. This is actually an adjustment point for each end of the scale. You'll notice in earlier pictures that the needle wasn't quite to the 'C' like it should be. I corrected this through use of the upper adjustment point.
This better illustrates what you're adjusting. You can see the teeth up tward the top pf the gauge within the housing on one side and the teeth and hole are somewhat visable on the lower right side of the gauge. Two adjustment points, one for each end of the scale.
Here is a picture of the matched sending unit to the '57-'60 gauge.
Part number: B7A-10884-A
Dimensions: 1/4 X 18 X 15/16 Long
Fits: 1957-1962 CARS AND TRUCKS
Seen available on eBay for $15 +shipping.
And there you have it! in order to make the gauge function properly you must have the voltage reducer to bring it down to 6v and also have the matching temp sending unit, in this case a sender for '57-'60 trucks.
One could possibly use a guage/sender combo out of another car or truck even later than '60 provided that the main gauge housing is the exact same dimensions (depth and diameter) and needle sweep
. If the main housing matches you'd just swap the rear mounting plate and face. I looked at alot of different gauges on eBay and noted alot of similiarities of these gauges in both cars and trucks thru at least '66 in trucks and I believe '60 or '61 in the cars.
It's also my belief that this can also be used for older pre-'55 vehicles aswell, if one was to switch to 12v and/or the original senders to the 6v gauge are unavailable or too pricey. Again- as long as the main gauge housings are the same, they can be swapped
Anyways, there you have it. I'll be buying a temp sender here soon for the '57-'60 gauge to positively confirm its much smaller size but if anyone here wants to chime in to verify, be my guest.