My 55 bird (Fordo) has developed a fairly loud tapping noise which i initially thought (hoped!) might be the exhaust banging against the chassis member but find that unfortunately it's not. It seems to be coming from the rear of the engine area and is noticeable on idle and pulling away particularly if on incline. The engine was reputedly rebuilt not long before I bought it and runs well. Reading through the forum archives I read that a cracked flex plate could be the issue. Is there an easy way to check this? And how big a job would it be to rectify?

Many thanks

Richard