finally finished the conversion in my cab, it started a1 but when it warmed up to "warm" the water system became under pressure and got so bad it blew a hole in the header tank on the seem. checked cylinders for loss of compression there fine there is no signs of fumes in the header tank, its got a new thermostat what else could be the problem.
thanks juff

 

well did you bleed the system of air...........

 

yeah did that by taking of the small pipe on top of the thermostat housing,

 

you did what

Its a self bleeding system?!

 

How do you bleed the system of air in the water