Pontoon Boat & Deck Boat Forum

2010 115 hp Mercury 4 stroke outboard. Removed the lower unit to replace the impeller and we can't get it back on the last 2 inches or so. The problem appears to be the gearshift shaft on the lower unit not going into the shaft on the upper half. There is a white collar that just sits completely loosely around the shaft on the bottom if attempting to leave it on the lower unit when reinserting, or you can insert it onto the gearshift rod coming down from the top and it holds in place. It came off with the lower unit when we removed the lower unit initially. THe white collar has a slit in it for some reason (wish I had taken a pic) but doesn't seem to align with anything. We've had 2 people wiggling the lower unit while someone pushed the white collar with a screwdriver trying to somehow make things align. We could always put it in gear or spin the shaft on the lower unit but we're afraid that will possibly make the throttle/gear selector be wrong. I'm going to try to include pics if I can remember how, or a link to my facebook page where the pics are located. https://www.facebook.com/photo.php?fbid ... 906&type=3 Looks like the link works but let me know if you can't see it and I'll make it public.

I hope someone can answer this because I will be doing this with a similar model. All I read said to turn the prop to align everything.

I have a service manual for this model but won't be back in town until Saturday.

Taylorjm, I watched a couple on you tube and thought "looks easy enough". Didn't go just like the video but there were many similarities. I was glad a young cousin down the street was available to help since it didn't go as expected. I don't know that I would try this without a vise or some way of standing it up securely. I also found the extra set of hands very handy due to weight/awkwardness of handling this odd shaped piece. I didn't buy the official MERCURY kit but kind of wish I had now. It was about double the price and had a rubber gasket (I really can't describe) rather than paper or something similar and was kind of 2 sided so there was only 2 instead of 3. THe kit also had 3 orings leftover and had me wondering so I called the seller and they said that was a semi-universal thing to cover a broader range of years. The next poster has us covered, I think, just not today.

LOL, you ARE the next poster! I have since learned that I should work the gearshift lever in the cockpit while someone is lifting the foot to get it to line up, but I'm not taking that as gospel until I hear it from at least one other source or hopefully more. He also said some models require it to be in forward gear to work/fit/align. He suggested just snugging 2 bolts after getting it on and changing the shift lever. Said as long as it spins both ways in neutral, the correct way in f and the other way in r and it should be fine. Said it would only turn one way in f and other in r but I don't know why it wouldn't spin both ways by hand. I think f is clockwise as viewed from the back but better google that. Let me know what you find in the manual as I won't get to fix this until Sunday evening. If I KNEW it would go back on in 10 minutes, I'd find the time before then, but I'd be up crap creek if it didn't and lining up a helper ain't easy sometimes. I've never had an impeller changed but it looks like this one really needed it so glad I did. I've got a 1998 2 stroke Evinrude that's never been changed but I haven't run it in 2 years because it started missing so badly without a relatively simple fix. Might merely be the carbs but I'm afraid of working on a carb.

Last time I changed a impeller (many years ago), I had the engine and the lower unit in neutral. When putting the lower unit back on, I had someone slowly move the throttle into forward gear and the lower unit slipped right up into place. Give it a try.

It's hard to believe my new boat's already 4 years old--which would usually be time to change the impeller. But I'm very low hours on the motor and our lake's water is very clean. And Yamaha's impellers are longer lasting than some other brands.

Looking like that might be the answer. Thanks.

Man I had a rough time of it too. The rubber mallet helped!

I'll bet if he holds his mouth right and puts hair around it, it'll slide right into place.

Tried that. Can't get the hair part right. I'm sure hoping the throttle/gear manipulation is confirmed by others.

I pull my mercury lower every year for the last ten years. Not hard for me as long as I put it in forward. That way I can rotate the prop a little to get it aligned and started. I always put grease on the splines of both the shaft and gear teeth. One year I neglected to put it in forward and could not get it on for anything. I wound up putting it in gear on the boat and gently with a cloth and pliers turning the gear shift teeth to put it in forward. That worked fine after oh about a dozen attempts. I would put it on and then check if it was in neutral when I shifted the controls. If you do that be very careful and don't crank it if it is not in neutral by spinning the prop before trying to crank the engine. It may be cranking in gear! Very dangerous. I was amazed by how little the gear shift teeth needed to move to be in gear or neutral.

If you are manipulating the prop I would either disconnect the battery or pull the kill switch just in case.

[quote="jrolin1"]I pull my mercury lower every year for the last ten years. Not hard for me as long as I put it in forward. That way I can rotate the prop a little to get it aligned and started. I always put grease on the splines of both the shaft and gear teeth. One year I neglected to put it in forward and could not get it on for anything. I wound up putting it in gear on the boat and gently with a cloth and pliers turning the gear shift teeth to put it in forward. That worked fine after oh about a dozen attempts. I would put it on and then check if it was in neutral when I shifted the controls. If you do that be very careful and don't crank it if it is not in neutral by spinning the prop before trying to crank the engine. It may be cranking in gear! Very dangerous. I was amazed by how little the gear shift teeth needed to move to be in gear or neutral.[/quote]
Thanks. Sounding like that's the way to go. Do you normally put it in gear before removing the lower unit or just when you are reattaching it?

[quote="mpilot"]If you are manipulating the prop I would either disconnect the battery or pull the kill switch just in case.[/quote]Thanks for the safety tip. Curiously, I wonder just how much you'd have to spin it? I think the only guy who knows is 3 finger Joe.

[quote="albow"][quote="jrolin1"]I pull my mercury lower every year for the last ten years. Not hard for me as long as I put it in forward. That way I can rotate the prop a little to get it aligned and started. I always put grease on the splines of both the shaft and gear teeth. One year I neglected to put it in forward and could not get it on for anything. I wound up putting it in gear on the boat and gently with a cloth and pliers turning the gear shift teeth to put it in forward. That worked fine after oh about a dozen attempts. I would put it on and then check if it was in neutral when I shifted the controls. If you do that be very careful and don't crank it if it is not in neutral by spinning the prop before trying to crank the engine. It may be cranking in gear! Very dangerous. I was amazed by how little the gear shift teeth needed to move to be in gear or neutral.[/quote]
Thanks. Sounding like that's the way to go. Do you normally put it in gear before removing the lower unit or just when you are reattaching it?[/quote]


Before removing it. The one year I did not was a royal pain.