R4 Project> Coolant Pipes & Hoses


Coolant Pipes & Hoses


In order to fit the electric water pump and under-seat radiator, the coolant hoses and fittings need to be replaced or modified.

A coolant flow diagram from the FZR400 service manual can be downloaded here.


Coolant Outlet Tube

Outlet tube The top coolant outlet fitted to the engine has to be removed and modified. After bead blasting some corrosion can be clearly seen. bung The vent pipe needs to removed and reversed to suit the new position of the radiator. bung and the damaged end needs to be cut off and a 90 degree elbow fitted. Hole Done! The piece that was added was cut off the intake pipe. The angle is actually tighter than 90 degrees to get a clear run back to the radiator. Finished with zinc plating.


Coolant Inlet Tube

Inlet tube
Rather than trying to make a new inlet tube it was easier to just buy a second-hand item from an FZR600 and cut it up as required. The original Yamaha part also has the bead at the end of the pipe that helps to retain the coolant hose.
Inlet tube
Cut the pieces to the appropriate length and weld together.
Outlet tube
Test fit the assembly
Inlet tube
The finished piece zinc plated.