My Wife has 63 Valiant convt. The engine has been replaced with a later 2806830-9 block casting # and the Radiator is a 3673904 which denotes a 1973 car. I assume the engine is from the same car but I havent looked at the stamped numbers. It does have Chrysler Electronic ign. I was flushing the cooling, and pulled the therm. and it is a 180. By 73 were they running a hotter Thermostat? It seems to run really cool , about half way between "COLD" and the first "NORMAL" mark,.,,THNX RH,,,,,,,,,,,, PS top tank thermometer says it running 170
Correct Thermostat
- Thread starter Road Hog
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The 180 should be fine for you, assuming it is doing its job. To verify you might want to get an IR temp gun and shoot at the thermostat housing after the engine is fully warm. That will tell you what the real temp is.
Kendog 170
Let the boy go !
Do above. It may also be your gauge temp sensor on the motor. If you still have the old motor you could try swapping the sensor.
@slantsixdan can tell you exactly what it should have.
slantsixdan
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Along with the later block probably came a later head. The temp gauge senders changed for '64, and the '64-up senders have a different resistance profile than the '60-'63 senders. The early senders are larger, too, so you can drill and tap (with a magnet in place of the thermostat, to catch the chips) the sender hole to accept the larger early sender compatible with your '63 temp gauge. You'll probably have to change the terminal on the temp sender wire (back) to the pre-'64 type.
Specifically, the early ('60-'63) senders have 13.5 - 15.5 Ω resistance at 220°F. The '64-up senders have 15 - 19 Ω resistance at 220°F. So a later sender, with its higher resistance, is going to make an early gauge read low. The '63 sender is this one.
180° is the spec thermostat temp for your '63, and that holds good no matter what year the engine is from. Sounds like yours is opening too soon — parts quality being what it is these days (i.e., poor), it's more important than ever to pan-test a new thermostat: pry the valve open, push a string through and let the valve close on it, tie the other end to a pencil or chopstick or similar, put the chopstick across the top of the pan so the stat is suspended/not touching the pan, fill the pan with water, and heat it up while you stir it with a thermometer. The thermostat should drop off the string at not less than 180°.
It is not the case that cooler and cooler is better and better; read this to understand.
Specifically, the early ('60-'63) senders have 13.5 - 15.5 Ω resistance at 220°F. The '64-up senders have 15 - 19 Ω resistance at 220°F. So a later sender, with its higher resistance, is going to make an early gauge read low. The '63 sender is this one.
180° is the spec thermostat temp for your '63, and that holds good no matter what year the engine is from. Sounds like yours is opening too soon — parts quality being what it is these days (i.e., poor), it's more important than ever to pan-test a new thermostat: pry the valve open, push a string through and let the valve close on it, tie the other end to a pencil or chopstick or similar, put the chopstick across the top of the pan so the stat is suspended/not touching the pan, fill the pan with water, and heat it up while you stir it with a thermometer. The thermostat should drop off the string at not less than 180°.
It is not the case that cooler and cooler is better and better; read this to understand.
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Scody21
Just send it
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I’d put a real mechanical temp gauge in it…
slantsixdan
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…and come to think of it: if this temp sender difference was ignored during the engine swap, and this car has an automatic transmission, pretty good odds the need for a spacer ring to properly adapt the '68-up large-bore crankshaft to the '67-down small-nose torque converter was also ignored. Fixing this will be a nuisance — either the engine or trans has to come out, slightly and briefly — but the transmission damage that will result from continuing to drive without that ring will be a bigger, more costly nuisance.
Dan, the sender does look like to one you pictured. It has the same type of terminal. I installed a new 180 thermostat, It runs 170 in the top tank and 180 at head with a temp gun, where the sender is located. gauge still reads 1/2 way between cold and normal. Thanks, RH
slantsixdan
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Ah, well then maybe you have the '63 head on the later block, or someone already drilltapped for the larger/earlier sender. Top tank temperature reading is a whole lot more accurate as far as coolant temp goes than any reading you can make at the head with a temp gun (remember, the head is also being heated by exhaust), so I still suspect your thermostat is a little lazy.
No, I'm afraid you can't see that spacer ring just by removing the inspection plate. The ring in question goes in the counterbore on the crankshsaft's rear flange, to support the torque converter's nose.
No, I'm afraid you can't see that spacer ring just by removing the inspection plate. The ring in question goes in the counterbore on the crankshsaft's rear flange, to support the torque converter's nose.
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