115 Mercury shift sync.

IB6UB9

Cadet
Joined
May 5, 2006
Messages
11
Dropped the LU and installed a new impeller. After help on the forum was able to get a full stream from the impeller. <br />Backed the boat down the ramp, put it in reverse and it leaped forward. What the hey, I can handle the reverse for forward and vice versa until I get home. Then the faint smell of gasoline. Long story short, a fuel line got pinched when the engine was tilted installing the new pump. Floated the boat back on the trailer. <br />The boat was going forward when it stalled . Dropped the LU in the driveway, then shifted the lever into forward to match the LU. Bolted all up. I now only have reverse! Any suggestions besides installing a “Zipper” on the LU?<br /><br />Justin
 

nos1013

Petty Officer 3rd Class
Joined
Mar 6, 2006
Messages
97
Re: 115 Mercury shift sync.

Been there, done that! You have to just sit down with the LU with vise grips on the shift shaft and the drive shaft. Turn the shift shaft until you feel it "shift", then turn the drive shaft clockwise, and see where you're at. Then, shift it again, etc until you find Forward, Neutral, and Reverse. After that, shift the shift shaft to Reverse, and the controller to Reverse (check the manual for alignment points. Then, methodically align the shafts and mate them up. <br />Good luck, BTW. It took me several stabs to get it right!
 

Clams Canino

Commander
Joined
Jan 10, 2004
Messages
2,179
Re: 115 Mercury shift sync.

I use neutral to put them up - but the idea is the same.<br /><br />-W
 

Boatin Bob

Lieutenant Commander
Joined
Sep 24, 2001
Messages
1,858
Re: 115 Mercury shift sync.

I'm with Clams, I know the book and several peole say you have to have it in forward but after spending a couple of frustrating long hours trying that I put it in neutral and the damn thing just fell into place!
 

IB6UB9

Cadet
Joined
May 5, 2006
Messages
11
Re: 115 Mercury shift sync.

Thanks for the expert advice! Before I drop the LU again and do the vise grip trick..... I know the unit is in reverse because the prop rotates freely clock wise and moves the flywheel counter clock wise. Knowing that, would it not work to drop the unit, put the shift lever in reverse then go back together?<br /><br />Thanks,<br />Justin
 

IB6UB9

Cadet
Joined
May 5, 2006
Messages
11
Re: 115 Mercury shift sync.

Sorry.....I was bass akwards. The gear case is in forward. It rachets clockwise and turns the flywheel counter clockwise. I dropped the LU and noticed I could turn the shift shaft coupler 300 deg. before it stops. Should this be turned all the way clockwise or counter clockwise before attempting to install the LU?<br /><br /><br />Thanks,<br />Justin
 

IB6UB9

Cadet
Joined
May 5, 2006
Messages
11
Re: 115 Mercury shift sync.

Got it! Bolted up, all gears and peeing a great stream!<br />I used neutral to sync the shifter. Glued the rubber bushing on top of the impeller housing with silicone, coated the outside of the bushing with vaseline.Worked like a charm. <br />For those that are attempting this for the first time remember never turn the drive shaft or the flywheel counter clockwise during installation. Turning counter clockwise will turn the impeller blades in the wrong direction. The impeller will not pump or correct it's self with the blades going counter clockwise. Found that out the hard way.<br />Thanks for your help!<br /><br />Justin
 
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