Motor slipping out of Gear

[RustyFF3]

I just replaced the water pump on a 2000 Yamaha V-max 200hp, took the boat out to check it, water pump is working great, but while running on plane it RPM's suddenly jumped and it seemed like the drive shaft slipped, took off again and it happened again, just alittle quicker. I feel like I must of did something wrong installing the lower unit back on, since it had no problems prior to fixing the water pump. Any help would be greatly appreciated

[99yam40]

drive shafts are splined and do not slip unless the splines are stripped.
maybe you are having a problem with the prop hub slipping( spun hub)

[RustyFF3]

Thanks for your response, I thought it may be the prop and I will check it, but are there other things to lookfor? Like something did'nt get aligned back right or seated back in it's original position, are there some common mistakes made when installing a lower unit back on that I can check? Thanks again for your response

[rodbolt17]

if you have f n and r you hit the splines correctly.

[RustyFF3]

It did, I pulled it back off, just to retrace my steps, now(without the motor running) when I shift it into F N R the prop spins freely,seems like its not engaging the shaft, still feel like everything went back right. Any suggestions?

[99yam40]

Lower unit will not bolt back up if the drive shaft does not go into the crank properly.
But you may be able to miss the shift shaft coupling.

Always good Idea to watch carefully as you put it back together to make sure you get the shift shaft and water tube into the proper places.

with motor tilted up it gives you a better view of things as you slip the lower unit back on

[RustyFF3]

Thanks for the responses guys, it is the prop slipping on the hub.