UPDATE !
I have spoken the the nice chap at Cornwall M.B. about my dilema and he will talk direct to marx about replacement parts which would save me the expence of buying the whole unit , this may also help both ways as most companys rely on feed back either positive or negative and future units may be built differently.
Expecting a reply next week.
But i cant grumble mine was second hand when i bought it and has been running for about five years

.
Oh and a big thanks to ministeve for the offer , later bud .
daz