Nissan 25horse 2-sroke stalling out after hitting rock with prop

Hey everyone, thanks ahead of time for your responses. It's turkey season, so this is my new priority:

My nissan 25 horse two stroke (NS25C3), year 2003, has been giving me trouble. Here's the story, I was cruising down river at full speed, and bam I hit something (still don't know if if was a rock or tree). There was slight prop damage, but nothing abnormal for the speed I was going. I immediately started the engine back up, with no problem. I put it in gear, no problem. I putted down the river checking everything out, and felt as if I had gotten lucky, that is until I accelerated.
At about 25% throttle it clangs, and stalls out (i describe it as someone dropping a bag of pennies). Initially i did this 3 times trying to get back to the launch, upon the third stall my pull start froze ( and i was able to get it loose by twisting the prop around. I have since pulled out the drive shaft and prop shaft, and have seen nothing wrong (no bends, the splines look fine). My friend told me to check my shear pin, but I'm unsure if my engine has something different because I can't find a shear pin on the diagrams I have.

I have taken apart the lower end and looked around, but being as this is my first real boat/engine I am still somewhat new. I'm pulling her apart today, and want to see where you guys would be looking.

Thanks again!

No shear pin. Your prop has a rubber hub, which may be bad now. It's intended to shear to save the gears, and then to let you limp home. If sheared, it isn't usually noisy, but typically slips at speed. I would pull out the prop shaft housing and inspect the gears. There may be some gear teeth floating around in the LU.

Are you referring to the gears in the prop hub (If so, I do not see any).

The gears in the lower unit otherwise look fine, I did find a couple metal shavings but other than that have not found anything. I unsure what would be bad inside my prop shaft housing though.

Could you give me particulars? I see nothing about a "hub", but know your talking about the 21, 22, 23, 24, 25 in this diagram.

http://www.boats.net/parts/search/N...5C3/DRIVESHAFT HOUSING - GEAR CASE/parts.html

** Sorry I meant to say the gears in the prop shaft housing

I have not taken off the lower unit and tried running it, however it does run fine every time I start her up. It also seems fine when I put it in gear, forward or reverse. The problem is when I attempt to plane out because at about 25% throttle it clings and dies. Then starts first pull again. There was a little water and LU oil around my prop shaft after the initial incident.

Hey, thanks for the replies. I pulled apart the lower, and it seems to be the needle bearing for the drive shaft as it enters the LU next to the water pump. I didn't think the bearing would've gone out from hitting my prop, but i guess thats the best case scenario!

I apologize, as I am not too good with the lingo. What do you mean by gearbox? my housing seems to be fine, I am replacing both bearings for my drive shaft as it enters my lower unit. I have taken apart the lower unit (and pulled the drive shaft out of the unit), inspected all of the gears, and see nothing wrong with them. The bearing was literally destroyed, and it definitely got metal shaving all over the place which is why I'm replacing several different parts, including the lower pump case, and gaskets with it.

and while Im at it, I am buying a new shim, which goes with the bearing. However there is a 0.15, 0.3, and 0.5 shim…. which one do I use? they all "fit" my engine, but what is the difference?

If you did not change gears, You can use the same size shim. Otherwise, it is a complex and time-consuming process to shim for correct backlash. The needle bearing will not affect backlash, so go with the same thickness you originally had.