1977 Merc Lower unit install

[sutor623]

Sup guys, I just got an impeller in and was trying to install my L/U on a 4.5hp 1 cylinder 1977 Merc. Now, there is a water input line, shift shaft, drive shaft, and two studs that have to slide in. My question is this, do the driveshaft AND shift shaft enter the splines at the same time, or does one enter slightly before the other. This thing is a BEAR to get back together. I can't get either shaft to seat. I almost wonder if one of my shafts is slightly bent. Any ideas?

 

[sutor623]

Re: 1977 Merc Lower unit install

anybody got any insight?

 

[mercuk]

Re: 1977 Merc Lower unit install

Pete, I sympathise with you, they can be a right pain to put back together somethimes. I would probably say the shift shaft splines first, then drive shaft at a guess.
Make sure you have the gearbox and shifter in the same gear. The once I start to aline it up, once is about 3/4 away from sealing, I gently turn the flywheel until the splines match. Works for me anyway. Good luck buddy, and just be patient with it, if it came apart alright it must go back together just fine as well!! :facepalm:

 

[sutor623]

Re: 1977 Merc Lower unit install

Yeah what a pain it is. Only issue is that I think the drive and shiftshaft have to enter at THE SAME TIME! I am hoping this is not the case but Im sure one of the gurus will chime in.