Hi I have 1985 Mercruiser 260 I/O. I am currently out of water on blocks. With engine off and control all forward or all reverse the prop locks as it should. All cables operate as they should, or so it seems, and cut off switch seems to be correct in cable positions. With engine running on muffs it stalls shifting into forward or reverse from nuetral. However if I disconnect the cut off switch it will shift in forward and reverse. Is this because the boat needs to be in water so there is resistence at the prop? Or do I have other problems I should look into? I would appreciate any input Thanks, Jeff