Hey everyone,
So people with a good memory might remember that I've been dealing with overheating issues basically the whole time I've been here. Well something odd is going on now. The water temp gauge I had in there was installed by a friend and was just your usual over the counter gauge, probably got it at autozone or something. The thing finally stopped working reliably (would read zero no matter what unless you jiggled the line) so I took it out and installed a gauge myself. This time not holding back, getting one of those 70 dollar Stewart Warner gauges someone on here recommended. Now I work in HVAC, I know these gauges use a bulb with a capillarity tube carrying refrigerant to move the gauge. The old gauge I thought was electric but turns out it was mechanical too and the line come to find it was all bunched up and pinched underneath the radio.. and I've heard how fragile those capillary tubes are on these things.. so who knows how good or bad that thing was running.

Anyway so my issue is this, with the hold gauge I was constantly fighting, teetering on the edge of overheating no matter what I did to the car whenever it'd get up to temp. Hovering around 190 to 220 on the hot-side stuck in traffic... basically made trying to drive the car a nightmare of worry. The last thing I did was remove the stock 4 fin cooling fan and installed a high-flow performance plastic fan with really aggressive curved blades, trying to keep this dang engine cool you know? Didn't really help very much.

So I install this new Stewart Warner gauge and now the engine is running too cold! Hovering around 140-145. Now once the car is up to temp, if you sit idling for minutes on end it will heat up.. think I got it up to 170 at most before I moved again. It'll raise and lower as you'd expect in stop and go traffic once warmed up. I even tested the gauge with boiling water before putting it in and while it took awhile to raise up it did get to 212 in boiling water. I've changed the thermostat twice since I owned the car and haven't driven it a lot since but it's been awhile so I couldn't tell you what it's rated. I'd assume 160-170 opening temp.

My question is this, do you guys think It'd make a 40 degree difference just switching back to the stock fan? I wouldn't think it'd make that huge of a difference. I'm happy not to have it wanting to overheat anymore at least by what the gauge says, but I also don't want to wear the engine running it so cold either.. I'm honestly surprised it's even that cold but I don't know how the gauge could not be working right.. I installed it very very gently and hardly even unwound much of the tubing it's still mostly all curled up under the dash like it came. What do you guys think?

Is the temperature gauge reading originating at the rear of the engine in the original temperature sending unit location?  If so, then that location will read 15-20°F lower than if taking the reading at the front of the engine right behind the thermostat.

Lorena, Texas (South of Waco)

There are many remedies here on this site you can research them. Do you have temp gun? I carry one in my glove box; you can tell a lot with one. For many of us a smaller water pump pulley solved our idle and traffic over heating. Other items include a 6 blade steel fan, a fan shroud, a stock seal from the top of the radiator support to the hood, etc. good luck.

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

Derale 8600B 6-blade, heavy-duty fan for 1955-60 models. I paid too much for mine. Had I known the brand and part #, it would have been a lot cheaper/w free shipping on Amazon. Now you know.

I had a similar issue... I changed a bunch of stuff and got it just right now.  The gauge read hot, then I changed to the smaller water pump pulley, then it seemed too cold, then I realized there wasn't a thermostat in there, so I put in a 180* thermostat and it kept getting hotter and hotter...then I think I changed to the thermostat below and also swapped in a new sending unit and my problems were solved.  

The NAPA 170* thermostat often recommended here (Napa Thermostat #6).  

The TBird forums are consumed with posts about engine heating issues as they were notorious over heaters. Every car is different. Driver expectations and local conditions are as well.  When I was a kid growing up in Miami, it was common to carry a gallon of water in your car trunk to refill a radiator gusher on a hot summer day, so this is not anything new.

Like others have said, the first thing is to find out what your engine temperature actually is. Temp guns are cheap enough.  My greatest improvement came from installing a modern aluminum radiator. The radiator you see in the photo below is a $200 Champion which included the electric fan.   Originality doesn't mean much when you are stuck in traffic on the Interstate with the temp pointer buried to the right.   As you can see, I don't have a shroud or an engine driven fan.  My electric fan runs all the time.  It makes a little noise, but it's not that noticeable.  Something most people miss is the engine timing and condition of the distributor advance mechanism.  Make sure the engine is in tune and the advance mechanism is functioning correctly.  The rest of the things like a 170 degree thermostat and improved water pump helped also. Here in Florida, I have to turn off my electric fan in the winter so my engine runs hot enough.  In the summer, our air temps are regularly in the mid to high 90s.  Our traffic is world class heavy and my Tbird engine temp stays under 200. This is an old photo before I installed an alternator. My engine is bored .060" over.

I RUN A CHEAP ALUM. RAD IN MY48MERC PICKUP,292 YBLOCK 4V HOLLEY 56 312 HEADS MOLLEY RINGS,SHADBOLTCAM,NO SPILL TUBES ON ROCKERS. NO OVER HEATING,ELCT FANS CONTROLED BY WATER TEMP SENDER. HEAT GAUGE AT TH FRONT,FED INTO HEATER WATER. PORT.JUST BEHIND THERM.
IF WATER CANT FLOW THREW THE  RAD CORES,FLOW OF WATER WONT SHOW ANY FLOW OUT OF THERMO,AS WATER PUMP IS CAVITATING AND  ENGINE GETS OVER HEATED. OLDER RADS  CANT BE CLEAND THREW SOAKING,TOP AND BOTOME TANKS MUST BE REMOVED AND TUBES RODED OUT. NOW YOU WILL BE PAYING BIG MONEY AND STILL HAVE A POOR RAD. SO CALLED CHEAP RADS WORK GREAT. IF 1 FAILS STILL CHEAPER THAN TTRYING TO JERRY RIG THE ORIGINAL RAD,PLUS SHORTEN THE ENGINE LIFE.

Thanks for the advice guys. Can't help but feels you didn't read my topic though. I'm saying my engine is running too cool.

If the thermostat is working correctly, then it is not too cool.  Verify with a laser thermometer at operating temperature.

Also take note of what Ted wrote.  The indicated temperature of the gauge will be lower than the highest temperature at the thermostat.  So the temperature you see at the gauge is in the ballpark for a 160-170 degree thermostat.

Changing the gauge won't have any effect on the operating temperature.  Whatever temp it runs at now is the same as it was before.  Your gauges just indicate differently.

Assuming that everything else is in good working order, a different fan should affect things at idle and lower road speeds, maybe under 20mph and it should have no effect at higher road speeds because the velocity of the vehicle will push air through the radiator faster than the fan can pull it through.  The fan really isn't required at higher speeds.  This is why electric fans and clutch fans are useful.



Lawrenceville, GA

Is your temperature gauge sending unit located at the front or the rear of the engine?

Lorena, Texas (South of Waco)