At last we managed to sort out the manifold bushes on the intake manifold .These are the bushes that are fitted to the "butterfly valves" and when they are worn there is a loud suction noise from the front of the engine.
Thanks Jotto for offering assistance but a friend staying close by assisted with these.
He tried 4 different materials , nylon ,vesconite and some other non metalic material but the only one that works is Brass and the centre hole needs to be wirecut as its an odd shape.
He has saved the drawings so as to cut bushes for anyone who needs.I will pass his details on to anyone who needs.
They also manufacture copper and aluminium gaskets
