[Ceili]

2005 2900 Coronet with 8.1 Crusader gas engines. Increased mechanical noise from Starboard transmission at idle in neutral.  Any trouble shooting ideas?

[jclark003]

The torsional damper plate that sits between the flywheel and transmission may be what you are hearing, especially if it goes away as soon as you pick up rpm’s. They will do this if a spring has failed or if the engine has developed a slight miss which is the more likely scenario. I’ve changed plates thinking they were bad only to discover a random misfire was causing the thing to clunk at idle.

[Ceili]

Thank you for the reply. Will run it up and see if it quite downs any.

[Ceili]

Thank you for the suggestion, pulled 7 of
the 8 plug wires (could not
reach the 8th) and reseated.   Started right up with no noise.  Sea-trialed up to 3400 rpm for a short period and cruised at different loads with no issues and no indication of any misfires.  Having the yard replace all plugs at winter haul out.

[jclark003]

Glad it wasnt anything serious.