What have I messed up now??

[thormx11]

This is my second attempt at changing an impeller (still trying to fix my first attemp on my inboard). The motor is a 1987 mercury 80hp 3cyl. and I was leaking oil from the water intake ports, so I ordered a new shift shaft seal and impeller to install. Did everyhting by the book, but when I re-installed the shift shaft in the lower unit it would not shift the lower unit, you could spin it completely without shifting the lower unit. What did I do wrong?


Thanks

 

[carholme]

Re: What have I messed up now??

It looks like you followed the procedure for disassembly correctly but in this case to just change the shift shaft seal, you should have left the shift shaft in the housing and splined to the shift cam while you just removed the two bolts and the bushing only.

Now that the shift shaft has been removed from the cam splines you have to fight to get the shaft re-engaged to the cam. Here is a picture of the shift cam and you will see the splines where the shift shaft has to fit:

http://imageshack.us/photo/my-images/828/glm11185.jpg/

In this link:

http://www.crowleymarine.com/mercury-outboard/parts/298_18.cfm

items 45/46 are spring loaded against the face of the shift cam and when you removed the shift shaft, the spring action has pushed the shift cam forward and mis-aligned it so you cannot insert the shift shaft into the cam splines.

I don't know how mechanically inclined you are but if you are new to this an easy option may be to just remove the prop shaft assy and reset the shift cam and insert the shift shaft.

Others claim to have had success getting the shift shaft reinserted into the cam without removing the prop shaft but you could be at it for quite some time.

Gerry

 

[thormx11]

Re: What have I messed up now??

When I removed the 2 bolts and bushing, the shaft came with it. From looking at the manual, it seems to be a fairly tough job to remove the prop shaft assy, and needs special pullers/tools for the gears.

Or is it fairly easy? I noticed 2 bolts right behind where the prop is, if i unbolted these 2 bolts would the assy slide out?

I am somewhat mechanically inclined (more than some, less than others), but new to boat engines/lower units.

 

[carholme]

Re: What have I messed up now??

You have the manual I sent you before and if you remove those two bolts, the only thing holding it in is the O ring. With the bolts undone
you should be able to rotate the carrier assy so that the ears are horizontal rather than the vertical position they are in now. This will give you something to pull against or tap lightly with a soft hammer against the portion of the ear closest to the carrier. Do not tap on the outer part of the ear as you will risk breaking it.

Just try and get the carrier back about an inch or so. so the cam follower will not interfere with positioning the cam. Then, remove the shift shaft assy and look down in there to see if you can spot the cam and with a long screwdriver or the like move it forward to the point that you can re-insert the shift shaft and engage the splines of the cam. If you can't see the cam, you may have to tilt and shake the LU a bit to get the cam to come into position. Once all is engaged again you can bolt the carrier back in and test the shifting using a pair of pliers on the shift shaft.

I hope I am not making this too difficult for you but it is pretty straight forward. If you have any questions, just ask.

Gerry

 

[thormx11]

Re: What have I messed up now??

I went ahead and pulled the prop assy out completely, and now I can shine a light inside and see better. I can see the cam, it looks to be bronze or copper in color. When I am trying to get it back in place, does it matter which way its facing? The cam is free and can be rotated/moved around pretty easily.

 

[carholme]

Re: What have I messed up now??

Good for you!

If you look at Section 5A, page 5A-18, para 5 of the manual, you will see the correct position of the cam with "UP" marked on the top side. It should be in that position now anyway and just try and face it forward is it is in the picture. then insert the shift shaft assy.


Gerry

 

[thormx11]

Re: What have I messed up now??

I have the shift shaft in the cam finally, I am about to replace the prop assy and see if I done it right.

 

[thormx11]

Re: What have I messed up now??

Looks to all be good now, I can shift it through through the gears fine. Should I have to use pliers though to shift it? On my inboard I am able to shift it with just my fingers.

 

[carholme]

Re: What have I messed up now??

Check shifting as follows:

a. Place shift lever in forward gear. Gear housing
should ratchet when propeller shaft is turned
clockwise and resistance should be felt when
propeller shaft is turned counterclockwise.


b. Place shift lever in neutral. Propeller shaft
should rotate freely in either direction.

c. While rotating propeller shaft, place shift lever
in reverse gear. Resistance should be felt when
propeller shaft is rotated in either direction.


Gerry

 

[thormx11]

Re: What have I messed up now??

Yep, sounds right. Got it all back together and sealed up, hooked the muffs up to the motor and fired her up and shifted perfect.

I can't thank you enough, theres no telling how much money you saved me from taking it to the local mechanic!

 

[carholme]

Re: What have I messed up now??

You did all the work and I'm just happy you feel good about it.

Good Luck!

Gerry