Reattaching lower unit

[Carl]

Has anyone had trouble reattaching a lower unit back on the motor after changing a water pump? I changed the water pump on Saturday and the job was going great until I went to put the power unit back on. I tried turnign the prop, (engine is in FWD) also turnign the flywheel. I can feel the splines trying to mate, but I don't have enough thread engagement on the studs to bolt it up. The shift shaft doesn't seem to be the problem. It seems like the drive shaft. I tried it both with the motor trimmed up, down and just about every angle in between. The water tube seems to fit fine and slides nicely. I even disassembled the water pump just to make sure that was right.

Any help is appreciated. Thanks

[BassyiusMaximus]

I know it might be tough, but it will help to have one person pushing the L/U up while another person "jiggles" the flywheel to get the driveshaft to sync, that would be my first thought. Did the shifter get moved? I know it is tough to get the water pipe lined up along with the shift shaft all the while holding the heavy piece up to get it into the housing but the only things that could stop it up would be the driveshaft splines or the shift-shaft splines binding up or not mating exactly to slide into each other, those would be the only 2 things I could think of.

I cracked my shift shaft where it mates into the splines, like as if someone sliced a carrot top at an angle. I had pushed the L/U up enough to get nuts on the threads , I kept torquing the nuts wondering why they were so tight, well the shift shaft was not aligned and all the pressure chipped a piece right off. I was able to JB Weld and along with a S/S clamp it broke off so clean that I was able to just glue it together and got it to work for the next 10 years but I learned my lesson after that, if the L/U doesn't easily go right up into that housing, drop it and rotate the flywheel or have someone rotate it until it slides up nice and easy. I had my girlfriend do it for me this past December when it hung up for a moment and thank goodness she was there or I would have had to move the flywheel ever so much every time to get it to mate and it would have been a pain. Good luck.

[NEXT2NUN]

I always put shifter in reverse before taking the lower unit off. Make sure you have water proof grease on the tip of the driveshaft hold the lower unit up and wiggle the prop until everything lines up. I like to trim the motor to about 45 degrees so you can get a knee under the skeg to hold some of the weight. Don't force anything. Look up inside the leg with a flashlight to make sure there isn't anything blocking the splines in the crankshaft.

[keeperreaper]

What next2nun said. The trick is reverse.

[Carl]

Thanks for the advice. Why is Reverse any different than forward. I realize that the shift shaft had turned a bit and the prop was in neutral, but I got that back in forward, but I didn't have time last night to try to put it back on the motor. I did have help on Saturday when I was doing the job. It would be very very difficult to do that job with only 2 hands.

Thanks

[macojoe]

You are going to have to make sure the lower unit is the same as shifter!! F, N, R or its not going to go. Other wise do like all has said!

Amazing how heavy that lower unit gets isn't!!

[MrHunters]

ive been told never to have it in neutral. i found out the hard way.
I was having trouble on my old 76 merc and tried changing the the position of the throttle toget it back together. well. it did go back but first time out forward, neutral and reverse were all forward.

that was fun. :dope:

[Roger]

Forward, reverse, neutral?
I'm pretty sure that different brands/models have different requirements.

[MrHunters]

Originally Posted by Roger

Forward, reverse, neutral?
I'm pretty sure that different brands/models have different requirements.

not sure if your asking me? but the gear pin?? not sure what its called completly missed the socket. again not sure what its called.... i just so happened to have it in gear when the lower unit went back on... if it were in reverse i would have had it in reverse for all three as well.

[Roger]

Originally Posted by MrHunters

not sure if your asking me? but the gear pin?? not sure what its called completly missed the socket. again not sure what its called.... i just so happened to have it in gear when the lower unit went back on... if it were in reverse i would have had it in reverse for all three as well.

That wasn't it - I wasn't clear. In the question of whether the engine should be put in forward, neutral or reverse before dropping the LU, I was stating that I believe that different brands/models have different requirements. It's not the same for all motors. My Honda needs to be in N, while I'm sure my old Johnson needed to be in gear, though I forgot which.

Thanks for taking the time to answer the question you thought I asked.

[nightfighter]

Originally Posted by Roger

In the question of whether the engine should be put in forward, neutral or reverse before dropping the LU, I was stating that I believe that different brands/models have different requirements. It's not the same for all motors. My Honda needs to be in N, while I'm sure my old Johnson needed to be in gear, though I forgot which.

Absolutely correct. You need to check shop manual BEFORE unbolting the unit. Hoping to do water pump, impeller, and change oil this week. Anxious????? Naw.....

[MrHunters]

glad i didnt get into how the fire started... now THAT was some scene

::end off topic::

[NEXT2NUN]

Roger back when I worked on outboards for a living. Mercruiser and Mercury had to be in reverse. I don't recall it making a difference on anything else so we just put everything in reverse. At the time Hondas biggest outboard was a 10 HP (yea I'm old)I never took one apart.