78 merc 75 lower unit

[tysonb]

I just replaced the impeller on my '78 merc 75 7.5 hp. I am trying to put it back together and was wondering what was the trick on getting the shift linage set right. Which way should the shaft be turned when the shift lever is in the middle position? My kids must have played with it while I was working on it.

 

[FLATHEAD MAC]

Re: 78 merc 75 lower unit

SET CONTROL in forward, and LU in forward. prop should have resistance going counterclockwise, and click when turning clockwise

 

[tysonb]

Re: 78 merc 75 lower unit

Thanks. I have both set in neutral now but ran out if daylight yesterday. Will that work or does both have to be set in forward?

 

[FLATHEAD MAC]

Re: 78 merc 75 lower unit

As long as both are in same gear setting youll be ok . You can read many post and diferent strokes for different folks

 

[hotrod53]

Re: 78 merc 75 lower unit

Agreed, just stay away from REV gear, it has less of a notch to fall in and in some can be kinda spring loaded. FWR and Neutral are definate positions and work better when aligning.

I assume that you confirmed that the shaft length was the same, the shift shaft and driveshaft splines are the same, both either had a preload pin or didn't have a pin on the top of the shaft, right? Otherwise it will not fit no matter how well its aligned.

Also remember not to turn your driveshaft backwards while doing this, that impeller gets put in a certain way and trying to run it backards is not a good idea, rock your flywheel to mesh them instead.

 

[tysonb]

Re: 78 merc 75 lower unit

Thanks guys. I got it all back together and still wouldn't pee. Took it back apart and the rubber boot in the top of the waterpump housing got pushed crooked and wasn't right. I guess I am have problems guiding my water pipe onto it.

 

[water world]

Re: 78 merc 75 lower unit

take a flash lite and check bushing on bottom of power head. old ones were plastic new ones are fiber