1979 Mecury 90 hp lower end question.

[cjmesk]

I have a question about putting the lower unit back on. Does it need to be in forward gear or neutral when I put it back together?

 

[Laddies]

Re: 1979 Mecury 90 hp lower end question.

The manual says fwd gear, I like to use rev as there is less chance for the unit to jump into a different gear the main thing is that the unit and engine are in the same gear.

 

[cjmesk]

Re: 1979 Mecury 90 hp lower end question.

It seems to me that it is stuck in forward. i think something in the lower end is messed up.
The shaft that goes into the lower end either spins freely or is in a stuck position. But the prop stays the same in forward no matter what.
Is there something I am missing?

 

[emckelvy]

Re: 1979 Mecury 90 hp lower end question.

The shaft is likely not stuck. The "spinning freely" part is just the range of possible motion of the shift shaft when the gearbox is in FWD.

To shift the lower unit to Neutral, grab a pair of Vise Grips or other suitable pliers; cushion the jaws with tape etc to keep from marring the shift shaft splines; then rotate the shift shaft CCW until you feel resistance. Continue rotating the shift shaft and you'll feel a bit of a detent. This should be Neutral.

Confirm by spinning the propshaft. If you were to continue shifting in the CCW direction from Neutral, you'd find Reverse. But don't go past this point.

If you leave it in Neutral it's most likely to stay there unless disturbed.

Now shift the gearbox to Neutral also and things should go back together better.

You'll need an assistant or Very Long Arms to rotate the flywheel slightly during the final few inches of travel when reinstalling the lower unit. This allows proper engagement of the crankshaft and driveshaft.

Needless to say, be sure the ign is off and plug wires pulled from the spark plugs when you're doing this!

HTH.........ed