stumiister
Diesel Truck Tech
I replaced the thermostat in my truck yesterday, the PO installed one that looks like it belonged in a small block ford or Chevy, I went to the local International dealer to get one it was a bit pricey but I needed it, I was surprised when I started the truck after I was done how much a difference the new thermostat made, Im curious though what is purpose and function of the check ball in the upper piece of the thermostat housing?
