JHZR2
Staff member
Was reviewing the FSM for my 96 Cummins 5.9L. I was interested in the bypass system, and the fact that the thermostat has a dual spring setup to block the bypass when warm.
Some aftermarket thermostats dont have the second plunger that blocks the bypass. So the bypass would then be open all the time. If that’s the case, I’d understand that cooling may be less efficient because it’s blending some coolant that’s just circulating in the block, not forcing all flow through the radiator. But is that a bad thing? Unless max cooling is essential, could this be a good thing?
Or, is an unblocked bypass going to permanently allow preferential flow in that circuit, and be problematic?
thanks!
Some aftermarket thermostats dont have the second plunger that blocks the bypass. So the bypass would then be open all the time. If that’s the case, I’d understand that cooling may be less efficient because it’s blending some coolant that’s just circulating in the block, not forcing all flow through the radiator. But is that a bad thing? Unless max cooling is essential, could this be a good thing?
Or, is an unblocked bypass going to permanently allow preferential flow in that circuit, and be problematic?
thanks!