1958 35hp sea horse long to short conversion

vernonfarmer

Cadet
Joined
Jul 4, 2007
Messages
7
I've just acquired a nice '58 sea horse 35hp electric start (RDSL-20). It has a long shaft and I need to convert it to a short shaft motor. I have a short drive shaft and would like to hear from any of you who have done this conversion. Questions include: how do I shorten the shift rod? Which end of the water tubes do I cut off, top or bottom? Since the spacer is 5 inches, is it safe to assume I cut five inches from the water tubes and shift rod? How do I cut the notch in the shift rod? Is that it? Anything else I need to do to go from long to short?
Thanks,
John
 

lindy46

Captain
Joined
Nov 27, 2008
Messages
3,886
Re: 1958 35hp sea horse long to short conversion

So you have a factory long shaft with the long shift rod (short connector) and one-piece water tubes?
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: 1958 35hp sea horse long to short conversion

Why are you wanting to do this? I have a 12' tinny with a long shaft 9.9 and it works fine.
 

1946Zephyr

Vice Admiral
Joined
Oct 21, 2008
Messages
5,556
Re: 1958 35hp sea horse long to short conversion

It's very likely, infact almost positive, that you have the longer water tubes and longer lower shift rod, with the short coupler. In order for you to change your motor to a short shaft, you will need a shorter drive shaft, shorter water tubes (these models have two) and you will have to pull your lower unit apart to replace the lower shift rod. If you would like a conversion kit, I can help you out. ;)
 

vernonfarmer

Cadet
Joined
Jul 4, 2007
Messages
7
Re: 1958 35hp sea horse long to short conversion

I have a 15.5" transom on a 14' Cruisers Inc. Holiday. That long shaft is going to keep me in deep water!
As i said in the original post, I already have the short shaft. Why couldn't I just cut off the shift rod and file the notch for the coupler screw? I'm told there is a shift rod seal/o-ring?
 

1946Zephyr

Vice Admiral
Joined
Oct 21, 2008
Messages
5,556
Re: 1958 35hp sea horse long to short conversion

The shift rod 0-ring is in the gearcase. If you have any water intrusion in your oil, you may as well open up the gearcase and convert it right. Doing things like the good ol' shade tree redneck may or may not work correctly. :D:D:D If you don't cut the shift rod off the right length, that will screw up your shift rod adjustment.
 

vernonfarmer

Cadet
Joined
Jul 4, 2007
Messages
7
Re: 1958 35hp sea horse long to short conversion

I sure don't want to screw up my shift rod adjustment! What would you need for a conversion kit minus the drive shaft?
 

1946Zephyr

Vice Admiral
Joined
Oct 21, 2008
Messages
5,556
Re: 1958 35hp sea horse long to short conversion

You will want the lower shift rod linkage and the two water tubes. You could cut the water tubes easily enough, but you may decide to use the long shaft conversion in the future. If you intstall the short shaft shift rod conversion, you can get the 5 inch coupler and easily convert back to a long shaft. If you want the lower shift rod linkage and water tubes, pm me and we can work something out that we both can easily work with.
 
Top