The Fleece CLNTBYPS-CUMMINS-12V Coolant Bypass Kit is a must have on any high performance Cummins Engine. The
Cummins engine cooling system was designed to adequately cool a
300-350hp engine. When horsepower is increased there is also an
increased demand on the cooling system. The rear cylinders suffer from a
lack of coolant flow, and therefore, experience the highest coolant
temperatures. This can cause excessive pressure to build in the system,
especially the rear of the block and possibly blow out freeze plugs
externally, or the smaller diameter plugs under the valve cover, leading
to a failure.
Weve designed our coolant bypass kit with a secondary thermostat,
that unlike other brands, works based on temperature instead of
excessive pressure. This solves the problem before pressure becomes an
issue by ensuring consistent temperatures across all six cylinders. Our
kit comes with high quality O-ring fittings and AN hose connections with
braided hose to ensure a leak free installation.