Hi, I am new here and I will like to request some help, I have a 1985 Renken with a 3.0 140 Mercruiser. The mechanic replace the second coupler already but it still doing the same. It will engage forward and reverse just fine, but when I accelerate it seams to desengage the gear and smell rubber like the coupler is bad. If slowed down again it will idle once more. The mechanic replaced two couplers and fixed the front support of the engine mounting. According to him that was in bad shape and provoqued that the engine was out of aligment. It suposed to be fix now but I still have the same issue. Please I need Help, I spent a lot of money without possitive results, Thanks.