Install and align shift cam in lower unit for Mercury 90 hp 4 stroke

[bpboater]

I replaced the seals on this mercury 90 hp 4 stroke (2001 model). I have the service manual, but the pictures of the shift cam do not look like mine. After I put the lower unit back together and re-installed it on the boat, shift pattern is backward. When I shift in forward, the prop goes in reverse. When I shift in reverse, the prop goes forward. I wonder if I put the shift cam in upside down, which would reverse the forward and reverse locations. Is there any other possibility to predict this behavior?

Bpboater

 

[Maxz695]

Re: Install and align shift cam in lower unit for Mercury 90 hp 4 stroke

Prop should click in one direction and lock in the other direction in fowards the prop should spin freely in both directions in neutral and the prop shold lock in both directions in reverse. If this is not what you have you have improperly installed the LU and it must be taken down and the thottle lever must be in the same position as the lu when going back up. Tha cam should be on the lowest dentent in fowards facing the front most point of the LU when in fowards. The hi dentent shoud be facing the foward most point of the LU when the LU is in reverse. The cam should be between the Hi and low dentent facing the foward most point of the LU when in neutral Prop spins freely then set the shifter in neutral the sock it back up

 

[bpboater]

Re: Install and align shift cam in lower unit for Mercury 90 hp 4 stroke

OK, so I turned the shift cam over with the numbers facing up and now the shift pattern is correct. Thanks for your input.

 

[WyoHntnDude]

Re: Install and align shift cam in lower unit for Mercury 90 hp 4 stroke

OK, so I turned the shift cam over with the numbers facing up and now the shift pattern is correct. Thanks for your input.

How do you align the shaft to go back in the pinion gear in the lower unit?

 

[GA_Boater]

Re: Install and align shift cam in lower unit for Mercury 90 hp 4 stroke

Please start a new thread with your question. None of these posters are around anymore. Thread is close to two years old.