Lower unit making noise MC-1

[Arrace]

Hey guys, I am putting the lower unit back together with the upper unit (mc-1) in my 78 mark twain 898. Now when I put it back together I rotate the shift shaft clockwise while rotating the prop counter clockwise, it locks and then when I put it together I make sure that the boat is in forward gear. To my knowledge now the lower unit and upper unit(boat) are both in forward gear.

Now I also notice that when I rotate the prop forward (clockwise) while in forward gear it takes a bit of effort (not too much) then it makes a really loud clicking sound.

When the upper and lower are seperated when I hold on to the shift shaft in full clockwise and rotate the prop clockwise and it clicks as well. I'm not sure if I am doing something wrong or if this means that my lower unit is bad. I only have reverse, and neutral as well. If you need any more information let me know, thanks!

 

[ktbarrentine]

What you are hearing/feeling is normal. When rotating the prop CW by hand with the shifter in FWD, you are "ratcheting" over the shift dogs. Go the other way with the prop (CCW) and it locks (like you observed). The opposite occurs when you are in REV (shift shaft rotated CCW to about 10 oclock, then rotate the prop CCW.... ratchets. Rotate CW and it locks in REV. Dont know what you mean by "I only have revers, and neutral as well."

 

[Arrace]

Sorry for the confusion, not sure why I said I only had reverse and neutral. All I have is forward and neutral. Forward on lower unit when boat is in forward and neutral with the shift lever. When I put the lever in reverse all I get is neutral. Does this mean that the shift boot that goes over the splines of the shift shaft is off by a spline and needs to be rotated?

I've noticed that when the boat is in reverse that the shift fork at the bottom of the upper unit will rotate freely between reverse and neutral, while in forward it locks forward (facing the starboard). Does that mean that something is broke in the upper?

I've tried putting the lower unit into reverse while the boat is in reverse to mate them, and while it is going together the lower unit makes a popping noise and goes back to forward gear. (locking CCW) and cicking going CW)

I just want to make sure that I'm putting them together correctly, so to make sure. I put the boat in forward gear, then rotate the prop counter clockwise until it locks (I've noticed that when it locks it will spin the input shaft counter clockwise) I put a bungie around the prop to hold it counter clockwise so it doesn't spin out of forward. Then I mate the two together, The shift shaft goes into the splined boot and the foot fits into the fork in the top, this is when I still only get forward gear and neutral when shifting the boat and going back to the prop and rotating it. Sorry for any confusion, I'm just having a heck of a time putting them back together.

 

[ktbarrentine]

Did you happen to have the upper half of the outdrive off the boat at all for any of this maintenance? Starting to sound like your shift shaft roller is disengaged from the shift slide fork where the upper bolts on to the bell housing. If it were me, and just based on the symptoms you've been describing, I would take the upper half off the boat and put the upper and lower together on the bench (I tend to like to do it that way anyways because then I get to do all my other checks on the drive and transom, like u-joints, bellows, gimbal bearing, outdrive pressure tests, etc). None-the-less, when you get the drive put together on the bench., you can do your bench checks on the operation of the shift shaft. Then you can work at putting the drive back on the boat, ensuring your shift cable slide fork properly engages the upper shift shaft roller.

Before you do any of that, though, did you make sure you have installed the rubber washer and stainless steel washer on your splined shift shaft before mating the lower to the upper? That would do it, too.

 

[Arrace]

would that be part 38 and 39 on this diagram?
http://www.iboats.com/Mercruiser-MR-...view_id.272969

I didn't take anything off the shaft when I took the lower unit apart, I'll have to go look at it. I don't think that there was anything on top of the bushing but I'll check to be sure. I'll let you know if those are missing and I'll see if I can't order some. Is the metal washer just a regular flat washer? I do have a bunch of small rubber washers in my water pump kit so maybe one of those will work. Thanks, I'll check that soon
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http://www.sterndrives.com/How_to_do_it/AlphagenII_ShiftLever.jpg

Turns out it was the shift lever that wasn't all the way in the slide fork, it was sitting in front of the teeth instead of inside it. Therefore forward gear on the boat was super far forward on the lower unit, netural was still forward, and reverse was neutral. Never would have thought that it would have been up here, but I guess the previous owner must have not put it back together properly. Also I was missing the washers on the shift shaft in the lower unit, found a nylon one that fit in my waterpump gasket set, and then just grabbed a stainless steel flat and put it in there. That's all working perfectly, thanks!