# Mercury Lower Unit?



## hightide78 (Jul 6, 2008)

I have been helping my brother-in-law replace the water pump on his 1986 175 Mercury. We tried to put the lower unit back on, but it stops about 2" from being in place, any ideas as to why? He thought about taking it somwhere to have it put back on, along with replacing the thermostats. I did not think it would be a good idea to trailer it without the lower unit attached, fearing something might get knocked out of place.


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## sosmarine (Sep 28, 2007)

At 2" it sounds like your vertical drive shaft isn't aligned with the splines on the crank. Put your controller in FWD. Rotate the shift shaft CCW (I think). Turn your prop CCW it should lock. If it doesn't turn you shift shaft CW. Once you have the lower unit in FWD you can use the prop to turn the vertical shaft and align the splines. Beofr you bolt it all up make sure the shift shaft is engaged. Put it back it Nuetral and Rev to make sure it's good.


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## DOUBLE "D" & LV (Oct 2, 2007)

I'm with sos on the most common simple thing, splines not lined up. Also, one thing that will happen is the crankshaft seal that the drive shaft geos into will fall off and block you from putting the unit together. It can be moved without pulling the powerhead to replace it, but you will fight it every time the foot is off. 

As far as towing it with the foot off, no problem. the water tube is the only thing that would come out. You can tape up the bottom if you had to. If you get stuck, I am mobile. Are you around pcola?


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## hightide78 (Jul 6, 2008)

Thanks for the advice, I was thinking it had something to do with the splines. My brother in law had it in forward when he removed it, where it still remains, should I put it back in neutral and go from there?I am located in Mobile.


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## Telum Pisces (Sep 27, 2007)

> *hightide78 (7/25/2008)*Thanks for the advice, I was thinking it had something to do with the splines. My brother in law had it in forward when he removed it, where it still remains, should I put it back in neutral and go from there?I am located in Mobile.


Leave it in forward. If drive-shaft splines don't seem to be going in place and up, you can turn prop counter-clockwise to turn drive-shaft splines. If you accidentally turn prop clock-wise in this step you will probably have moved shifter back to a Neutral position so use care. 

If unit has jumped out of gear you may have to turn shift-shaft (little shaft in front) COUNTER-CLOCKWISE to obtain Fwd. gear.

Sometimes you just have to hold your mouth just right. I have been there, done that, have the T-Shirt. One time I just walked away for a while and came back only for it to slide right up there after I had tried forever to get that damn lower unit to go all the way up.


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## DOUBLE "D" & LV (Oct 2, 2007)

That's right. You goota hold your mouth right.


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## chasintail (Oct 4, 2007)

I just put a new impeller on my merc this morning.Had the same thing happen.I just put my prop back on and while pushing up i turned the prop counter clock ways and it slipped in like butter.When you turn your prop ccw it will feel like it is not moving but it only has to move the shaft ever so slightly to line up.Good luck


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## Captain WhupAss (Nov 8, 2007)

Yeap. All that is right...


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