Hi all.   After about 1000 miles since rebuild I've had a constant problem with fumes and a general smell of petrol/exhaust when the windows of the car are open. I noticed yesterday that the engine had developed a ticking noise under load so I thought 'ah ha!' maybe I have a manifold issue. I've stripped the manifold off and found a few issues as can be seen in the pics attached. 1. The left most port appears to be corroded- and the gasket has burn/wear marks .   2. There appears to be a crack on the right centre port.   3. The exhaust deposits are quite white .   So I presume this is the cause of the noise but is it repairable or scrap? Thoughts please.     Many thanks   Paul