switching lower units??long shaft to short shaft

[troysidwell]

need to see if this can be done??
I have a good running 1982 115 long shaft ,and a 1979 115 short shaft that is seized up.
I don't want to run a jack plate,so my question is,can I just install the short shaft lower onto my long shaft motor??I have searched and came up with nothing.i know the water pick up tube will have to be cut down 5'',but should that be it?

 

[Chris1956]

Gee, I would think it easier to swap the powerheads. I believe the midsections are different as are the driveshaft and water tube.

 

[troysidwell]

but its just the lower unit that has the extra plate on it to make it a long shaft??I know the water tube is longer,so that would have to be cut..

 

[Chris1956]

Normally those motors have a longer midsection to make them a longshaft, plus the gearcase has a longer driveshaft. You can use the shortshaft gearcase, but you still will need the shorter midsection, and watertube.

If you have an extension plate on the longshaft motor, I have only seen them on much newer motors. You might verify the year of the longshaft motor.

 

[jimmbo]

need to see if this can be done??
I have a good running 1982 115 long shaft ,and a 1979 115 short shaft that is seized up.
I don't want to run a jack plate,so my question is,can I just install the short shaft lower onto my long shaft motor??I have searched and came up with nothing.i know the water pick up tube will have to be cut down 5'',but should that be it?

15" is a short shaft, 20" was considered a long shaft and, 25 " was an extra long shaft. In 79 and 82 only a long and extra long were made. To make your shorter one fit on your longer one, you will have to disassemble the gearcase to swap the driveshaft.

 

[Faztbullet]

but its just the lower unit that has the extra plate on it to make it a long shaft??

If it has a Bay Mfg kit on it, just remove the spacer,driveshaft extension and longer studs and bolt up an go

 

[GA_Boater]

It's time for a couple of pictures so we can see what you can see.

 

[jimmbo]

If it has a Bay Mfg kit on it, just remove the spacer,driveshaft extension and longer studs and bolt up an go

Driveshaft extension? When I check the mercury parts catalog, I see a long and an extra long driveshaft, and two different gear cases, one for long and one for extra long. No removable 5 inch housing spacer is listed

 

[GA_Boater]

Yes.

 

[jimmbo]

I would love to see that attached to an inline 6

need to see if this can be done??
I have a good running 1982 115 long shaft ,and a 1979 115 short shaft that is seized up.
I don't want to run a jack plate,so my question is,can I just install the short shaft lower onto my long shaft motor??I have searched and came up with nothing.i know the water pick up tube will have to be cut down 5'',but should that be it?

 

[Faztbullet]

I would love to see that attached to an inline 6

POOF!!!!!
Here ya go......

 

[jimmbo]

POOF!!!!!
Here ya go......

What does your pic have to do with the adapter that was shown by GA?

 

[Faztbullet]

Driveshaft extension? When I check the mercury parts catalog, I see a long and an extra long driveshaft,

What does your pic have to do with the adapter that was shown by GA?

Its shows a Bay kit installed on a Merc inline and GA pic shows the longer studs,5"driveshaft extension along with water tube and shift shaft extensions.The extension is for a smaller hp motor ....