stinger390

I have a slight rattling / knocking noise coming from the rear end of my 72C transmission seemingly inside the transom assy. The motors were out this winter and this particular transmission only has about 30 hours on it since rebuild. I also had it bench tested this winter prior to bolting it back onto the engine and it recieved a clean bill of health from the Mercruiser high performance dealer that serviced it. The TRS had a new u-joint installed last year, and I greased it this year. I also replaced the o-rings on the driveshaft, and greased the splines before installing the drive. The tranny fluid was changed and is type "F". The bearing in the tailstock was also replaced last year, and looked fine this year. The transmission works fine, as does the drive but just has this annoying little rattle that I want to make sure is ok. I noticed this noise last season as well and did not really worry about it, but I really want to make sure before I drop the boat in. Any other experiences with this annoying little rattle back there? It is not a slow loud knock or bang, just a fast low volume rattle that seems to go at the rate of a vibrating driveshaft. Alignment is perfect.

Thanks

z.zuperboat

Its Hard To Guess Without Hearing It But If I Had To Put Money On It My Guess Would Be The Flex Plate. What Your Hearing Are The Srings Moving Around. Should Go Away In Gear.

MrCIG

It could be the tin guard on the front of ythe bell housing. They tend to crack around the bolt mounting holes then rattle.

Mark

stinger390

I listened again......reverb from the stainless Shotgun muffler flappers causing a rattleing sound up the pipe. I like simple stuff.

thanks