Alfa 1 knocks ONLY in forward and ONLY in the water

[martexcap]

1993 Bayliner 2252 with Mercruiser 5.0 and Alfa 1 replaced from another boat 2 years ago by th seller.
I`ve got a boat for one year and everything was fine. Starts knocks recently and now knocks harder. Didn`t hit anything underwater. When boat on trailer with flusher attached runs fine ahead and revers. Prop turns freely by hand but you can move prop and shaft for about 3 mm back and forward with nand. Too loose?
On the water runs revers fine but knocks forward. No noise like bearing gone. Put wheel hard aboard in revers engaged - no knocks. So U-joint supposed to be OK. Called merc mech, he said possible chip on gear. Thanks Vic

 

[Bondo]

Re: Alfa 1 knocks ONLY in forward and ONLY in the water

I'd Guess it's time to Pull the Drive,+ Inspect the Transom Assembley.......

It you Don't find Anything There,...... Send the Drive out for an Overhaul.......

 

[martexcap]

Re: Alfa 1 knocks ONLY in forward and ONLY in the water

Thanks I expected thats a common trouble

 

[180shabah]

Re: Alfa 1 knocks ONLY in forward and ONLY in the water

Don't think I'd call it a common problem.

If you do need to overhaul the drive, check out SEI before you spend any money, you can probably replace the drive for less than it will cost to fix.