Kurtis, Randall,
John Hamer and I kind of discovered that when the Triumph factory went to
sleaveless thermostats for later TR4As they reduced the bypass hole in the
waterpump manifold port from approximately 9/16" to 5/16". The late manifold's
castings were revised.
If you don't have the late manifold with smaller bypass port hole you can
effect the same by installing a small washer with 5/16" hole, into the bypass
hose, either at the thermostat port or the waterpump manifold port end.
To prevent the accidental loss of this reducer-washer when changing out
hoses, some folks instead screw in a brass plug into the cast iron manifold
bypass
port, then drill it out to 5/16" for a more permanent fix.
If the Triumph factory solved the sleaved thermostat issue by reducing the
bypass port's size - and you can now do it for a nickel - why not?
Carl
'63 TR4 since '74
|