claybill Posted July 16, 2011 Report Posted July 16, 2011 well i took my 41 coupe with 318 automatic to a car swap and sale about 2 hours drive...it runs like a top and all is good after 1-1/2 hours the temp run up a bit...i stopped, and steam coming out of overflow..and water level was really low. topped it off and continued..no leaks. i am running the original radiator which has no system pressure regulator,(cap) i [probably need to upgrade the radiator with a pressure system..yes.? using a 180 thermostat. would it run cooler with a 160.? any info appreciated. bill Quote
Big_John Posted July 16, 2011 Report Posted July 16, 2011 About 20 degrees cooler. Yes and no... The thermostat opens when the engine is 20 degrees cooler. The temperature the engine eventually reachs depends on a lot of other factors. Quote
Jerry Roberts Posted July 16, 2011 Report Posted July 16, 2011 (edited) Once the engine warms up , the thermostat opens (if it is working) and the thermostat no longer controls water flow and temperature . 160 or 180 degree thermostat makes no difference to your high temperature if you are running hotter than this . On the other hand , if your thermostat is stuck your engine will overheat . If your thermostat is working , your problem is elsewhere . You can test the thermostat by placing it in a pan of hot water to see if it opens . Is your radiator partially clogged ? Is the engine block partially clogged ? Does your lower radiator hose collapse at high RPM ? Do you have a coolant leak ? As to if your radiator has enough capacity for your new V8 , some one else will have to address that . Tim would know . Edited July 16, 2011 by Jerry Roberts Quote
claybill Posted July 17, 2011 Author Report Posted July 17, 2011 h-m-m-m-m-m--mm.... a 160 thermostat might let enough water thru earlier to stem off overheating... i'll try it.. i have boiled out 1 gallon of water/coolant in 1 hour and 15 minutes of driving...yes it is 93 degrees today. bill Quote
Andydodge Posted July 17, 2011 Report Posted July 17, 2011 Bill, convert the original radiator to run a pressure cap, get the radiator cleaned out to be certain its o/k, also run a fan either on the engine if space permits or an electric pusher/puller fan with a manual switch that allows YOU to turn the fan on when you want it, also a 160 thermostat and a coolant recovery bottle.........I have all these things more or less on my 318 Poly powered 40 dodge sedan and I only turn the pusher fan on in stop/start traffic, otherwise it runs on 180 degrees as shown on the original guage.......... andyd Quote
greg g Posted July 17, 2011 Report Posted July 17, 2011 it is where the vent release is situated not the ca[ that determins if the system is pressurized. If the outlet is in the filler and it is located avove where the gasket of the cap seals, then the cap pressure is valid. If the vent is below that or located at the top of the expansion tank, the cap will not make a difference. What is the actual temp of you system. I ask this because it is normal for an unpressurized system to puke out coolant it doesn't need. If you fill the rat to the top, you are defeating the room provided for hot coolant expansion with too much coolant. As a result when it gets hot it passes out through the overflow. If the collant level is just covering the core or about 1 inch higher its is sufficient, any more will be rejected due to normal expansion. Quote
chopt50wgn Posted July 17, 2011 Report Posted July 17, 2011 Any thermostat will open at the given set opening temp. But they are not fully open until they hit 15 degF above set opening temp. So a 160 will open at 160 but not be full open til 175. For every pound pressure cap a radiator has , it will boost the boiling point of water by 3 deg per pound. So a 15 lb cap will boost the boiling point by 45 deg added to the boiling point of water at 212 and you have 257degF before boiling. A zero pressure system will alow water to evaporate faster because there is no pressure. Sending units for most gauges is located at the front of the manifold near the top hose outlet. The sending unit is picking up the coolant temps as it passes that sending unit. The coolant is also at its hottest as it passes ,but it is also coolant that is leaving the motor, not whats in the block. If the pump, fan, radiator are doing there job, coolant temps in the motor should be cooler than what the gauge is reading. Just passing on some cooling knowledge.... Quote
Andydodge Posted July 17, 2011 Report Posted July 17, 2011 To run a pressure cap on an original style non pressure radiator, at least this is what I had to do was get the cap neck changed to the type that suited a pressure cap.......pressure caps, at least all the ones I have seen are shorter in height.......after a lot of stuffing around I ended up getting a new radiator made that used the modern style core, it was thinner than the original radiator and works much better......its in this........and has been in it for 25yrs or so....... regards, andyd Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.