Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

[Kenth]

I accidently misaligned the shafts during an impeller repair.There is a shift shaft coupling between the lower unit and upper shafts. Does this have to be positioned in any certain way? The console shifter is in forward position. I have rotated the lower shaft CW to its stop position and reassembled the unit but it has forward only(those rpm don't appear to be very strong), no neutral, no reverse. The only neutral is just past this "stop" position, but I have to hold the shaft in that position or it just springs back. That result is that the CCW prop rotation turns the drive shaft & CW just ratchets. I'm stumped.

 

[Texasmark]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

I have that engine and just recently replaced my impeller. I haven't done an impeller in years and this is the first for this engine and here is what I decided to do to ensure alignment:

I found that the shift cam in the LU moves about the least in N. Attempting to rock it back and forth attested to that as compared to other gears.

I put the remote in N. I brought the LU up and into position and with a wrench on the flywheel nut (remove the plastic cover with 4 wingnuts for access) I slowly rotated the engine until the drive shaft started to engage, didn't take but a few degrees. I then ensured that the shifter was lined up and put her together. Had the shifter not been aligned, a slight movement of the shift lever where the remote cable attaches would have done the trick. It works just fine and seems to be centered.

I like these newer engines where the water tube and shifter are held in place. Makes the stab a walk in the park as compared to older engines where the shifter is flopping around and you have to stab a soft copper tube with no support except where it is connected.

Mark

 

[carholme]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

If you don't have power trim, the coupling must be installed with the flat facing forward, shift rail set correctly and boat and LU in Neutral

What is your engine s/n? I can then send you the service manual if you PM me with an email address.

Gerry

 

[Texasmark]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

If you don't have power trim, the coupling must be installed with the flat facing forward, shift rail set correctly and boat and LU in Neutral

What is your engine s/n? I can then send you the service manual if you PM me with an email address.

Gerry

Mine has PTT.

Mark

 

[Maxz695]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

PTT usually but not always means no cam for the lockdown. As stated set the shifter in neutral the center most portion of the cable sliding shaft for the shifter. Then align the water tube and slightly turn the flywheel. It should go up all the way when splines line up if not just slightley move the sliding bracket to allgin the shifter and away she should go check for prop functions F lock in 1 direction click the other N spins both ways and R lock both ways after clutch dog is engaged. Then finish bolting it up. Good luck

 

[Texasmark]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

PTT usually but not always means no cam for the lockdown. As stated set the shifter in neutral the center most portion of the cable sliding shaft for the shifter. Then align the water tube and slightly turn the flywheel. It should go up all the way when splines line up if not just slightley move the sliding bracket to allgin the shifter and away she should go check for prop functions F lock in 1 direction click the other N spins both ways and R lock both ways after clutch dog is engaged. Then finish bolting it up. Good luck

On this engine in particular, Merc engineers have captivated the water tube and the shifter so you don't have to fish around for flopping shafts and tubes like days of old. I was pleasantly surprised to fine that when I dropped this LU.

Mark

 

[Maxz695]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

Please remind me to let this be my next project motor Tex. I was thinking 115 but 90 will definitly surfice

 

[Texasmark]

Re: Shift shaft alignment on2004 2 stroke 90hp. Mercury outboard

Please remind me to let this be my next project motor Tex. I was thinking 115 but 90 will definitly surfice

Like I said, I was PLEASANTLY surprised. Grin.

Mark