53 cadillac fresh rebuild overheating on break in.......help!

[mooman929]

Yes as good as could. 

[mooman929]

Ok so new update.  Since my gauge goes right pegged to hot, I took a thermometer and stuck it in the radiator and vCard heckled the water temp.  After 5 mins of idle it read about 180 degrees.  Is that about normal?  I just replaced the temp sensor last night.  Could it be the sensor is faulty or its the gauge?

[Coupe Deville]

Not positive on 53 but most thermostats open at 180 degrees. If you leave it running how much higher does the temperature climb?

[dadscad]

Not all parts house sender units are properly calibrated. These folks had the correct sensor for my 63, it works right. They have one for your 53.

http://www.lectriclimited.com/mainpage.htm

HTH, David

[mooman929]

It idled for a half hour and the water temp was 195 in the radiator .  With the gauge pegged

[Coupe Deville]

195 degrees is not that hot for prolonged idleing. It sounds to me like you have a gauge or sender issiue. When the motor is cold and you turn the key to the on position what does the needle do? Jump up a little or go to the pegged hot position?

[mooman929]

No it doesn't go right to hot it just creeps up there

[mooman929]

It creeps up pretty quickly as its idling.  And pegs hot but the radiator temp seems normal.  With a brand new sensor as well

[Jay Friedman]

Everything sounds normal now.  180-195 is normal temperature. 

My '49, with the same motor as your '53 and a 160 degree thermostat, will creep up to 195 and even higher while idling on a hot day.  (It does have some crud in the block.)  It runs at 160 to 185 when cruising at 30-60 mph depending on the temperature of the day, and will stay at about 190 when cruising at 65 + mph, particularly on a hot day when the sun is shining on the front of the car.

As someone suggested earlier, did you put a spring in your upper radiator hose?  Unless they are the flexible type, both hoses, even if pre-formed, need a spring in them to prevent pinching / collapsing at the bend. 

A good way to monitor the temperature as you drive is to temporarily install a mechanical temp gauge which can be bought at any parts store.  They are more accurate than the stock electrical gauge and are not influenced by the car's electrical system.  Remove the electric sending unit (what you have been referring to as the "sensor") from the back of the right cylinder head.  Hang or attach the mechanical temp gauge under the dash or just leave it on the front seat.  Run its capillary tube through a hole in the dash if you have one on a '53 or through the large hole for the right ventilation tube if you have one.  Using an adapter if necessary, screw the mechanical gauge's sending unit into the hole in the back of the right cylinder head and you are all set.

[Coupe Deville]

Jay is right on the money with the machanical gauge idea. That would give you a true reading. It could just be the gauge fouling you up. I have a friend who had a RV back in the 80s. It started to overheat one day. Temp gauge was all the way hot. He replaced water pump, thermostat, new radiator, while your there might as well replace hoses, belts......ect. $500 dollars later it stilled showed it was overheating. It turned out is was just a resistor for the temp gauge behind the instroment cluster. That one took awhile to figure out.

[mooman929]

Ok I'm hoping its just the gauge goin bad.  Thanks for all the help tho.  I haven't gotten this car on the road yet.  Gotta adjust the tranny bands then should be ready for a test drive.  Ill update everybody and hopefully all goes well thanks again