knock or chatter, outdrive shifts hard

[cobrasteve]

hi, I have just rebuilt my 4.3omc and after a short test drive I noticed a new list to the starboard side. cruised along for 10mins. at 3000rpm and started to hear a knocking sound after slight decceleration. when in neutral it sounds fine. started on my way limping to shore and found that it did not want to shift??? when it did shift it was very jumpy, awful. Ran the engine for 20mins at home on the hose and oil pressure and temp. was fine. ??? all seems the same as the 1st incedent where we found a "spun" rod bearing and a sticking? wrist pin. (conects the piston to the rod?) engine rebuilder said it is probably what we heard. always seems to go bad when I deccelerate????? could this be something knocking up through the engine from the outdrive? Boat is new to me (a holliday 200 cadorette) and found that it had been sunk! apparently the reason why I needed a new cranck, cam, rods, bearings etc. outdrive I hope as the engine cost a fortuned. Am suspicious of the shifting mechanisms... sos

 

[ErieRon]

Re: knock or chatter, outdrive shifts hard

I'm no Tech., and someone that knows better will be along, but you may want to check your engine mounts. Specifically where the bolt to the stringers. If the stringers are rotted, and your engine is floating around a bit, it could cause all of what you are describing and worse. I just went through it in the spring...bad list, no knocking or chatter though, I just spun my engine coupler when I went to set up a new drift while we were fishing. Turns out that all of the lag screws that hold the front mount down were loose because the stringer had rotted.

Just a thought.

Good luck.