Posted by Clint Dixon on Friday, April 09, 2004 at 9:25AM :
In Reply to: 165 degree Thermostat vs 180degree posted by Dave on Thursday, April 08, 2004 at 1:04PM :
I don't have my manuals in front of me, but I wonder if this change in thermostat rating coincided with the change from 6-blade fan to 4-blade fan?
My '47 WDX is cold-blooded compared to other Power-Wagons I have owned. I have spent years switching back and forth from 160 to 180 degree thermostats. I used to put a 160 degree in for summer and a 180 degree in for winter. Using a 180 degree in the summer makes the truck run 200+ degrees. I initially didn't care for this, and installing a 160 degree thermostat brought the operating temperature back down closer to 180 degrees. With the 160 thermostat in the winter, the truck would barely get up to 140 degrees, so I would switch back to a 180 degree thermostat to get the operating temperature back up closer to 165. This makes the truck run a lot better during the winter and I have finally settled on the 180 degree thermostat for year around use. I have gotten use to seeing 200+ operating temperatures in the summer and they do not seem to have any adverse effect on performance or engine life. I have to admit though, I am relying on the original dash guage. I have, however, checked my thermostats in heated water on the stove. The radiator was also rebuilt with a new core at the same time that I rebuilt the engine.
What I was getting at though, one tends to think that a 6-blade fan will move more air through the radiator than a 4-blade fan. From what I have learned, this is not necessarily true. If the change in thermostats coincides with the change from 6-blade to 4-blade fan, maybe Dodge found out that with more effeciant cooling resulting from using a 4-blade fan, that they could up the operating temperature of the engine to a more economical level with the 180 degree thermostat?
Or am I all wet? ;^)
Clint