force lower unit question

oteps · #1 09-11-2018, 06:49 PM

98 force 120. I am replacing the water pump impeller. Lower unit is off. I was going to shift it by hand but it is stuck in reverse? THe shaft moves a little over a half turn. Seems like the shaft on the motor moves about a spline width back and forth. THis motor has a splined shaft that turns not the one that moves up and down. Does it have to spin fast to shift into gear? My 175 merc wasn't like that.
History on motor. My father inlaw just purchased the boat. Ran 2 weekends but then shut off. My brotherinlaw "worked" on it. Had his buddy clean the carbs and put new plugs in. It ran on ear muffs but he said no water was coming out.
I should have ran it before I took the lower unit off but its an easy fix I didn't think about it then.

bradford · #2 09-11-2018, 07:07 PM

Wish I could offer quality technical advice, but the two parts that make me cringe is "brother in law" and "worked on it".

Someone with expertise hopefully will be able to talk you through it here soon.

oteps · #3 09-12-2018, 05:34 AM

I was hoping there was something simple I missed before I tear the lower unit apart.

oteps · #4 09-12-2018, 06:19 PM

Also there is no detent. From what I remember on my 175 there was a detent for forward, reverse and neutral. I might pull the gear case out tonight.

Destroyer · #5 09-12-2018, 10:18 PM

Force is Mercury. Mercury uses a splined shaft. On my 1993 Merc when I have the lower off for water pump repair I can turn the shift shaft by gently putting a pair of vice grips on it with just enough clamping force to hold on, then twisting in either direction to shift it. I would think the force would be the same. Try spinning the prop by hand while twisting.

oteps · #6 09-13-2018, 04:27 AM

I tried that. Nothing. I wonder if when I took lower unit off the shift shaft stuck and came out of the cam. I never had a shift shaft out. Not sure what holds the cam to the shaft.

phatdaddy · #7 09-13-2018, 08:39 AM

when u removed the foot, did u have it in reverse? like d says, the throw on the splined shaft in the foot is not very much.

if u don't feel like you have moved anything, i'd stick it back on the motor and test by spinning prop and shifting from the controls

oteps · #8 09-13-2018, 04:40 PM

I got it. Just had to turn the shaft like I was trying to break it. Somehow I must have turned the cam too much and was backwards. That's why it would spin half way around with no detent. Now I have all 3 detents.

Destroyer · #9 09-14-2018, 12:06 AM

Quote:

Originally Posted by oteps

I got it. Just had to turn the shaft like I was trying to break it. Somehow I must have turned the cam too much and was backwards. That's why it would spin half way around with no detent. Now I have all 3 detents.