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KLR650 Thermostat Bypass Installation Instructions
(See available PDF for printable version)
- Remove seat and fuel tank.
- Drain the coolant.
- Remove the 3 bolts securing thermostat.
- Remove original thermostat and set aside.
- Install brass elbow into bypass housing using Use Teflon tape or thread sealing compound. Elbow should point forward from top of housing as shown in diagram below.
- Install O-ring into original thermostat pocket on the cylinder head.
- Install new thermostat into bypass housing making sure the thermostat body does not block flow into the brass elbow.
- Using the longer stainless-steel bolts, install the bypass housing, thermostat, and thermostat housing on to the cylinder head.
- Cut the lower radiator hose about 3” from the radiator connection directly behind the frame down tube.
- Install the tee fitting between the 2 halves of the lower hose and use the 2 larger hose clamps supplied in the kit.
- Install the supplied bypass hose from the elbow to the tee fitting using the 2 smaller supplied hose clamps.
- Refill coolant system with coolant.
- Run engine until warm, then allow to cool and top up coolant level in radiator.