My '56 F-350 (223 six) needs a new temp sending unit, the original one is missing and has been replaced with an aftermarket sender and gauge.
From what I have found out, the '56 temp sender is different from all other years. Of course the older ones are 6V. But there is one listed for 1956 that has 2 prongs and one for 57 and newer cars that has one prong.
Of course the '56 only sender costs 4-5 times more...
Question is, I can only see one original cable on the truck that looks like it's going on the temp sender (coming from the loom on the firewall). Where is the other cable on those 2 prong senders supposed to go?
And can I use the 57-on sender if not to concerned about 100% originality?

Anders

 

Hi Anders,

Question is, where did you see the 56 sender with two prongs? I'm suspecting it was really mislisted as a 53-56 sender (as alot of things seem to be lately) and to be even more correct is is only for the 53 Flahead V8 - it's the over temp sensor (on the flatheads there were 2 senders - one was a simple switch to sense an overtemp, the other was the variable that drove the gauge)

56 was the only year in our vintage that was actually constructed for 12 volt gauges. 1955 and earlier were all 6 volt; and, 57+ were 6 volt with a voltage reducer for the gauge package

The critical issue is that the sender MUST be made for the gauge - so you can't flip flop on years - especially if one of them is 56. So you have a couple options:

1. You can spend the money and buy a true 56 sender;
or,
2. You can find a 53-55 gauge and a 53-55 sender (remember to get the single tab sender if it's listed as a 53 - that'll work) and simply swap out the gauge faces with your 56 (which is VERY easy to do) and install a runtz voltage reducer on the temp gauge. (which is what I'd do)
or,
3. You can buy a 57 gauge and sender, swap out the gauge face, and install a runtz voltage reducer on the back of it to run the 6 volt gauge on the 12 volt system. That's pretty easy too.
or,
4. You can spend the $$ to go to LMC and buy a new reproduction 12 volt 56 gauge and sender that match (electrically)

 

Thanks for a very good answer Julie! That leaves me with some options to get this working.

What made me get the impression that the '56 sender is one year only (as it is) and have two prongs is that NPD has the sender listed as "1956 -Two prong" and I have seen NOS senders on ebay that also has two, like this one:
1956 Ford & Thunderbird Temp sending unit NOS NR: eBay Motors (item 170546205828 end time Oct-05-10 00:08:20 PDT)

Anders

 

That's interesting because the one pictured at C&G Ford Parts (for $55) is two prong as well.

I'm not exactly sure why it would need two as the 56 wiring diagram only shows a single wire coming from the gauge to the sender (which is itself grounded) on the TRUCK wiring diagram. It's entirely possible that the 56 cars had a different requirement - I'll see what I can find. But th e2 prong sender should work fine for you.

There are three different styles C&G has:



Just as a side note I came a cross quite a few electrical diagrams the lumped the 53-56s together. And they show the V8s with two temp sensors as I mentioned above - which is flat out wrong. The 53/54 was wired quite differently than the 55-57s.

Let me lookl for some T-bird/car diagrams and get back to you.

 

I have not looked at what C&G has but this may also help someone with finding the correct unit.
1948-56 Ford F-100 Temperature Sender, 12 Volt, Original - B6C-10884

 

Did you notice that you responded to a 7 year old thread?

1956 temperature sending unit is 1956 only!

1956 is 12V, 1955 and earlier is 6V

1957 and later 12V temp sending units are different.

 

Yes, I did. I was searching for some info and found this one and one other when I was looking for info so I thought I would post what I had read just to help someone that was searching for the same.

Somewhere in my searching on this forum or another one, I did see a post where the poster made a comment about him using Teflon tape and wondered if that might be his problem?

 

Temperature sending unit? 56 f100 6cyl 12v. The one on the truck has 2 spades. Has org dash unit + someone added an under dash one but can only one of them. At the start, they would both read close to the same. Now either one of them is showing hotter than in the past? Flushed system and new fluid and new pump and no change and no steaming or boil over even when pegged. Ohm reading from spade to ground reads 50 ohms when cold and hot? So how the heck are the gauges even showing a reading? Can you advise me any at all as to what might be going on?
Thanks

C&G shows a two-prong spade for the 56 12v but Mid Fifties seem to be showing a 1 spade for the 56 and it looks like the two-prong one is for a V8?

Later this evening or tomorrow once I find the correct place to start a new thread I will re-post this and might get better results?

Time for me to get some work done.

 

There is only one 12V temperature sending unit for all I-6 & V8 1956 Ford, Lincoln, Mercury Passenger Cars & Ford & Mercury Trucks:

B6C-10884-A that has two spade connectors.

By the 1970's, this was almost impossible to find. Ford had obsoleted it, no one reproduced it, there were none available at auto parts stores, the Ford obsolete stores located here in SoCal didn't have any either.

1970: I lucked out, found 10 of them at a closed Ford dealer in the small Central Valley town of Kerman (CA) that I had stopped at during one of my trips searching for NOS parts.

The dealer had folded, the owner was conducting a parts inventory with two goofs he had hired from 'Manpower.'

It was laughable, the two goofs and the owner didn't know one part number from another, were looking in parts bin drawers for fenders and hoods!

I took over the inventory, spent the entire day there and was 'paid' by being given two NOS 1966 Mustang A/C kits and the sending units, that I sold very quickly several days later @ Harrah's swap meet in Reno.

 

Why are there two prongs on the sender anyway?

 

Abe,
I’d like to know that as well.

 

I have found two that give the correct number but have only one prong? Not sure if there is any wiring info in the factory manual if and when my friend can find where he put the DAMN thing. There has to be a reason that they had two prongs and not just a single one you would think?

I knew I had a nice gauge set that came with the bulb sending unit and I tested it yesterday along with something I use to take metal temps for my work. Looking at it with or without the extra adaptor then it should work. That should give us the correct reading and let us know if the oem one has gone bad or not and then go from there.

I will see if I can find a wiring diagram on the net and see if that will help with any info as far as the two prongs?

This is what I have found in the wiring diagram and the two prong one came on the V8. It also had the single one that is called the sensor and then jumps over to the double prong one that is called the switch. I guess the V8 had two mounting locations where the 6 only has one location but for what reason?
http://www.carsfromusa.de/files/2008...-1955-1956.jpg