Temperature Regulators Are Sticking Open Causing Low Coolant Temperature And Engine
Cold Mode Operation To Stay Active. Cause: low power running
Problem: On C-7 and C-9 on-highway engines the ( Jiggle Pin in the 115-4223 Water Temp.
Regulator may stick between the regulator valve and the regulator seat. When this condition
occurs engine will not reach normal operating temperatures and the engine will stay in the
cold mode operation. ) If the stuck in the regulator valve is found replace water regulator valve
with another 115-4223 regulator valve. C-9 engine install water temperature valve is installed
a 45 degree angle. make sure that the Jiggle Vale is installed in the six o'clock position. I have
posted this before but getting low power inquiries on this problem. It is a good idea to change
both water temperature regulators about every 2-3 years. At Branson Jim Nichols gave me his
regulator that was faulty to pass around group.
Dave Atherton Retired Cat Mechanic
