Wiring goes as so:

Battery "hot" to Ign. sw; ign. sw. to gauge; other gauge wire to sender; sender body is grounded through engine block back to battery "ground".  This completes circuit.  Other "tab" on engine "Sender" was for connection of "overheat switch" on right bank; eliminated due to "not found necessary" (read that "unnecessary expense" to Ford manufacturing = more profit).  Those switches can still be found [rare] and installed/wired to function as originally designed/installed.

That "extra" tab is NOT a ground; do not try that - it WILL burn-out your gauge in short order!

Regards, JLB




55 Ford Crown Victoria Steel Top

Should only be One Wire on Sender even though some do have 2 Terminals. Where does the second Wire go to if not the Gauge?  Maybe someone thought it should have a Ground Wire.

  

I have a 1956 ford heat gauge doesn't work, replaced sender, still does not work was going to trace wiring next. My wiring diagram shows on wire going from sender to gauge and one wire going to switch, my car has two wires going to gauge, what is the other wire for

I cant help but wonder if the fan speed is the critical isue at idel in gear,as you need air flow to exchange the heat fromwater to air.shrouds ar very critical as well as pans and belting wher air flowes around the radcore.we wher told in trade school that the hoter the water the better the heat exchang is but most important item is air flow threw the core.so the thery waswater flow threw was not as critical as air flow.So when the top tank aproches the same temp as the botem pushing more water threw the core will result in no change.once road speed comes into play more air flow the  temp rise is controled.pump cavitation is likely as stat opens and closes as more waterchanges direction.the post on the experiment re the tbird seemed to confirm ther problem was solved re shroud and blocking lost air flow .It is getting hot hear i sure hope my ranchero does not heat up,as the crow hear is not verry tastey. cliff

Whow..I never thought this would stir so much especially since this has been discussed about 2 years ago.. Greenbirds PM'd me over a year ago on the changing of the pulley to the 289/302/351 of just over 5", I was reluctant to do it and continually felt my 292 as built would at some point prove to me it could run at 175* in traffic/idle for what I would think was a normal amount of time. I'm not talking of going to Reno NV.for "Hot August Nights" and cruising for hours I just want to sit at a long signal and not have it heat up. As stated above it wasn't until I saw no movemet of water in the rad at idle especially in gear that I knew I had to do something. A Ford NOS temp sender at least made my gauge "tell the truth" when matched with a thermometer.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

just found a old book on all the facts re 1956 ford cars,page59 claimsall v8 engines in 56 came with  fords new4 blade ,silent spin fan. it goes on to say6cyl and the engines in thunder birds.use the proven3 blade type.page 61 goes on to say the cooling systems are deesighned to run13psi. it goes on to say externa bypass(internal in i-6) permits continuous recirculation of coolant when stat closed. also claiming top tank in rad has a difusor to eliminate bubles..

Re- engineering the 292/312 cooling system to function at hot idle, especially for an automatic in gear - is the main complaint I've seen on here over the years. Engines with the older spark advance systems were more prone to get "retarded" and heat-up - which just magnified the problem. Some vehicles got the problem solved with a fan change (especially those with the full sized radiator) - some got a bit better water flow with a more free flowing thermostat, and still better with the throttled bypass. Changing the pulley ratio jacks up both the fan speed (air flow) and the pump flow when the motor is sitting loaded against the converter at 550/600 rpm - and getting the job done with little evil. Mine is up about 20% - meaning that water and air flow potential at hot idle is now the equivalent of 670/730 rpm which does not approach "cavitation" - but does do a decent job of maintaining temperature equilibrium. I put a fan clutch on mine to slow down the fan at road speeds (per Hayden it slips 10% at full engagement). So what RPM do most of our cruising outfits run at highway speed - steady state? My money says virtually none of them would reach a point anywhere near "cavitation" and then stay there.   

 
 Steve Metzger       Tucson, Arizona

drylake you apear to have a rare problem. re by pass i went threw severl different engin cos,gm 8cyl engines al had by pass at the therm,some wher built in,all fords,except flat heads,early flat heads never had therms,so a constant water flowwas in play.we all know flat heads had history of over heat.my 47 ford pickup had heat isues esp at idel. cured buy drilling the back of both heads and ran a line to drain in both water pumps. end of problem. every diesel cat ever built from 1950s to 2000 had bypass tubes. most truck instalations had a small tank in rad with a shunt line to water pump as cavitation hapened when therms opened as pump could not get enough water for short time while flow changed. In your case i still feal ther is some other isue. cavitation does not damage the water pump but with bubles in engine block and heads lead to hot spots and cracked heads or blown head gaskets,as well as in acurategauges Hope you get to the botem of your isue and will make interesting read

Thank you Ted..I'll bet the 6.35" would have also solved my problem...

56 Vic, B'Ville 200 MPH Club Member, So Cal.

In looking at the Ford parts catalog, there were six different water pump pulleys for the 1956 Fords with V8 engines.  The diameters are as follows:

6.35” (extra cooling fan and 60 amp generator)

6.82” (A/C)

6.88”

6.94” (3 blade fan)

7.37”

7.44” (4 blade fan)

Depending upon the gearing and accessories, FoMoCo deemed it necessary to vary the water pump speed for the various V8 applications.

Lorena, Texas (South of Waco)