you've got your swill pot conected wrong.. the blanking plug should go on top of the thermostat housing and the pipe to the header tank should then go from the top of the swil pot...

I ditched mine last year as I didnt notice any affect, as a CVH has a built in swil pot, ie. the thermostat housing, the swil pot does look nice and shiny thou!

Nice motor!!! top stufF!