Hi all - thought it was a tappett noise but now I think its possibly the exhaust gasket blowing, getting a compression sound or hissy sound from rear cyclinder at the exhaust port, no issue with engine running but not 100% its the gasket, no obvious signs or worn pipe etc - any one got any thoughts? Looks like it may also be a full exhaust removal to get at it unless anyone knows any "tricks" thanks in anticipation...
