MC-1 shift shaft woes.

[PistenBully]

Hey all. I just got done replacing my impeller on my '76 Glastron with Merc 888 drive.

Does anyone have any words of encouragement when it comes to getting the shift shaft back together. It's older so it doesn't have the "foot" like I've seen in a lot of my searches here.

I put the drive into forward before dropping the lower.

I have been keeping positive CCW pressure on the prop shaft and have been able to get the drive shaft splines up into the upper unit.

I just can't get the splines of the lower shift shaft to mesh with the splines of the intermediate shift shaft. It's driving me crazy!

The stainless washer is there on the lower shift shaft. The upper unit is still on the boat. From what I've read, this job is easier on the bench, but I'd rather not if I don't HAVE to.

I've looked through my #2 Merc manual to see if there is a trick I'm missing, but there isn't much there.

Any help would be much appreciated.

 

[ziggy]

Re: MC-1 shift shaft woes.

#2 is the right book. so your good there.

The upper unit is still on the boat. From what I've read, this job is easier on the bench, but I'd rather not if I don't HAVE to.

you've read right. i've done what your doing. leaving the upper on the boat and just dropping the lower to change the impeller. imho, it's real painful to put the lower back on the upper when the upper is still on the boat. i know ya don't want to pull the upper. but there is pm to do when you do pull the upper. ie. grease the u joints, grease the coupler splines, check bellows and alignment, check for water intrusion etc. all that is good to do + when ya put the lower back on the upper ya can do it on the bench. i mate them by myself on the bench. it really is very much easier to do on the bench. not hard to pull the upper either generally speaking.
you do have the ''foot''. your just not seeing it because it's in the upper. tilt the drive up a little and look from the very ft. of the drive.

thats a '75 mc-1 drive in neutral (in fwd the shoe will be facing fwd instead of turned to port), you have a '76. it'll be the same drive as mine except for the gear ratio and the input shaft length since you got a v8 and i got an L6.

i know it seems like more work to pull the upper. but it sure will make mating the upper and lower together so much easier when ya take them off and put them on as a mated pair... really. try it. + do the extra pm while your there.

 

[Augie56]

Re: MC-1 shift shaft woes.

My '79 MC-1 is likely the same setup as yours, and the intermediate shift shaft has a cup on the lower end with a female spline pattern to match the spline pattern on the shift shaft it mates to in the lower unit. Not many splines from what I remember, maybe 6 or 8 total (?).

With everything locked in FWD, it might take some wiggling to get it to slip back together if the upper unit is still on the boat. Did you grease both the shift shaft end and the intermediate shift shaft end that it mates to? Some good marine spline grease will help, plus it will help fight corrosion when it's in the water.

 

[PistenBully]

Re: MC-1 shift shaft woes.

All righty then! I guess I'll pull the upper half of the sterndrive off the boat so I can take care of those PMs as well as getting the two units back together. What gaskets do I need to remount the MC-1 drive?

Thanks for the quick responses!:happy:

 

[Augie56]

Re: MC-1 shift shaft woes.

Probably just need a new outdrive-to-bellhousing gasket and a new o-ring for the cooling water jacket, assuming the assembled outdrive holds pressure and has whatever new seals/gaskets it needs.

 

[PistenBully]

Re: MC-1 shift shaft woes.

Hey All,

Thank you for the words of encouragement. With the help of a bungee on the prop and a little paitience, I was able to get it all back together.


I even got the this boat started for the first time in 6 or 7 seven years! The Ford 302 sounded pretty darn good too!

 

[Rake722]

Re: MC-1 shift shaft woes.

Hey All,

Thank you for the words of encouragement. With the help of a bungee on the prop and a little paitience, I was able to get it all back together.


I even got the this boat started for the first time in 6 or 7 seven years! The Ford 302 sounded pretty darn good too!

Better late than never - I found a great little workaround for the spline alignment after hours of huffing.

Get a friend to put a socket on the crank bolt and rotate the engine and drive slowly whilst presenting the shift shat to the upper - pops in in seconds.

Glad you got it sorted.

Ron.