1974 Mercury 115hp I6 2 stroke lower unit put back in help

[LubricatedKitten]

sorry for the poor wording on that title everyone I'm not sure what terms to use but I recently purchased a boat no idea what I'm doing lol I was able to get the engine to start right up following a lot of everyone's recommendations on other posts I was told to replace the water pump asap so i shut her down after knowing she would fire up and proceeded to take the lower unit off I put the boat in gear and took her out changed the water pump no problems just like the videos on the youtubes but now i cant get the thing back in, any suggestions? Thanks everyone.

 

[jimmbo]

Welcome to iboats

There are Splines on the Drive Shaft that have to mesh with ones on the Crank Shaft, same goes for the Shift Rod. Also the Water Tube has to go into a Grommet on the Water Pump. Crank-Drive connection is easy, rotate the engine until the Splines engage. The Shift Shafts only mesh in one location, if either the upper or lower sections were rotated then realignment needs to happen, both need to be in either Forward or Neutral. I just make sure not to move/rotate either while they are separated. One other thing, do not pull up on the Shift Shaft in the gearcase, that usually results in the Gear Case having to be taken apart to put that shaft back into the Cam that moves the Shift Mechanism

 

[LubricatedKitten]

Welcome to iboats

There are Splines on the Drive Shaft that have to mesh with ones on the Crank Shaft, same goes for the Shift Rod. Also the Water Tube has to go into a Grommet on the Water Pump. Crank-Drive connection is easy, rotate the engine until the Splines engage. The Shift Shafts only mesh in one location, if either the upper or lower sections were rotated then realignment needs to happen, both need to be in either Forward or Neutral. I just make sure not to move/rotate either while they are separated. One other thing, do not pull up on the Shift Shaft in the gearcase, that usually results in the Gear Case having to be taken apart to put that shaft back into the Cam that moves the Shift Mechanism

ah shoot i think that little spur gear got moved so ill need to take that aprt now too? how do i do that?

 

[LubricatedKitten]

I can spin the prop in one direction but not the other and when I do I see the little spur move a little and click as well as the main shaft if that helps at all on what I messed up

 

[jimmbo]

Don't start tearing the Unit apart just yet
I forgot that there is a Retainer, that is on the Shift Shaft that prevents one from lifting the Shaft out of the Cam, as long as the Bushing Assembly is not removed.

Try rotating the Drive Shaft, Clockwise when viewed from above. Does the Prop Shaft rotate? If so, which direction when viewed from behind

 

[racerone]

Stop.------You likely took it off with control in neutral.-----Then during your work it jumped into forward.--------So remove lower unit.------Turn shift rod with vice-grip to find neutral. and assemble.------Or put control in forward and lower unit in forward and assemble.-----No hammers required for this.----This mistake has been made hundreds of times !

 

[LubricatedKitten]

Don't start tearing the Unit apart just yet
I forgot that there is a Retainer, that is on the Shift Shaft that prevents one from lifting the Shaft out of the Cam, as long as the Bushing Assembly is not removed.

Try rotating the Drive Shaft, Clockwise when viewed from above. Does the Prop Shaft rotate? If so, which direction when viewed from behind

It doesn’t rotate smoothly it kinda jerks counter clockwise maybe half an inch but nothing more

 

[racerone]

Well----At the top of this Mercury forum is a tutorial.----third one down.----Explains how to correct this mistake.----Read it / learn from it.-----No need to take anything apart just yet.-----Hard to explain simple stuff sometimes !

 

[LubricatedKitten]

Well----At the top of this Mercury forum is a tutorial.----third one down.----Explains how to correct this mistake.----Read it / learn from it.-----No need to take anything apart just yet.-----Hard to explain simple stuff sometimes !

Thank you and everyone else i was able to get everything back together starts right up when i engage forward or revers it kinda sounds like someone who cant shift a manual correctly is that normal? also where is the throttle is that the wired tab on the control box thingy?

 

[jimmbo]

Now you are saying it cranks and starts the Engine when you shift into Forward or Reverse?

 

[LubricatedKitten]

Sorry I thought I got a comma in there, after I have the engine running and I put it into gear I hear a slight grinding noise like a bad shift if that makes sense.

 

[racerone]

You have to shift with a quick firm motion.------ Slow " granny shifting " is bad for the clutch dog.

 

[jimmbo]

There is No 'Easing' it into gear. It is either In or Out of Gear, so the quicker the Shift, the Longer the Clutch Dog and Gears last.

 

[LubricatedKitten]

All right that’s good to know would have never thought that lol awesome thank you all so much y’all have helped me a lot with this project, I just need some drain plugs and I can test her on the water

 

[LubricatedKitten]

There is No 'Easing' it into gear. It is either In or Out of Gear, so the quicker the Shift, the Longer the Clutch Dog and Gears last.

I did notice the rpms dont change when i put it into gear forward or reverse the only throttle change i get is by raising the natural lever did i do something wrong there? I noticed the same thing before i took it apart so maybe the engine is working 100%?

 

[racerone]

The control box first shifts the motor into gear.-----Then moving the lever more the engine gets more throttle applied.-----Raising the natural ( spelling ) lever is only for starting and warm up.

 

[LubricatedKitten]

The control box first shifts the motor into gear.-----Then moving the lever more the engine gets more throttle applied.-----Raising the natural ( spelling ) lever is only for starting and warm up.

Ok and if I push the throttle forward all the way and the engine doesn’t rev but the connecting cables seem to move inside the engine compartment thingy? Then what would that possibly mean?

 

[racerone]

Are throttle plates moving , yes or no ?----Are throttle and shift cables hooked up correctly ?-----Or perhaps there is an issue inside the control box.

 

[LubricatedKitten]

How would I check the throttle plates? I just got my repair manual in the mail today the only one I could find was the seloc brand not sure if there’s a page reference to try and find that part

Are throttle plates moving , yes or no ?----Are throttle and shift cables hooked up correctly ?-----Or perhaps there is an issue inside the control box

 

[racerone]

I guess I have to change the words.-----Are the 3 carburetors opening up ??