I had the same problem, the same advice (stainless prop), and the same
results as you. When they finally changed the shift cable to a new one,
everything was fine. They told me at that point it was recalled. The
odd part is that this was back in 2000. I have the 115 4 stroke EFI.

Dan


Donald Camps wrote:
I'm having trouble shifting out of neutral into foward or reverse...Gears
just seem to grind. The dealer and Mercury Marine say I need to run a
stainless steel prop....That helped a little bit, but they still make
grinding noises....Anyone else having this problem.....90 hp 4-stroke
Mercury Outboard 2004.