Standard to short shaft conversion?

howy · 21 April 2010, 21:09

Hi,
Can anyone tell me if it is easy to convert a standard shaft engine to short shaft please??

I have a 2004 ex RNLI Mariner 40hp standard shaft engine that I wanted to fit to a
TT-Supacat, but on closer inspection I cannot block the transom to the point where the engine will be in the correct position and mount it securely enough to be able to abuse it in confidence.

It looks as though the spacer can be removed easily enough, but of course that would be too easy, and theres bound to be something a great deal more complicated and expensive that needs doing.

Has anyone ever done this and if so is it straightforward enough or should I just sell it and buy a short shaft...

Hindsight.....

Many Thanks
Howy

Downhilldai · 21 April 2010, 21:18

Are you looking at reducing the mid from 17" to 15" or 15" to 12"?

howy · 21 April 2010, 22:31

Just from standard down to short which I think is 15"

Downhilldai · 21 April 2010, 22:35

Standard shaft is 15"
What size is your transom?

howy · 21 April 2010, 22:39

I thought short was 15, standard was 18, and long was 20"..?
I will have to measure the transom in the morning because I cannot remember (old age creeping in)

howy · 21 April 2010, 22:45

I think I may have confused the subject a bit.

I was wondering if I could take the spacer out of the outboard leg by the cavitation plate on the engine to take it from standard shaft down to short shaft

Nos4r2 · 21 April 2010, 23:06

Have a look at the water pipe. Can it be shortened? You should be able to remove the spacer and the driveshaft extension without dramas if it's an ex RNLI lump.

Downhilldai · 22 April 2010, 00:04

What about the gearchange rod? Would this also need shortening, or is there a coupling where you can lose the excess?

two stroke mick · 22 April 2010, 08:22

You should talk to Andrew O redrion as I sold him an Ex RNLI engine 17-18 " shaft. He converted it to a remote system and now has it on his tornado. It looks like a good job. He posts on this forum

TSM

Nos4r2 · 22 April 2010, 18:13

Quote:

Originally Posted by Downhilldai

What about the gearchange rod? Would this also need shortening, or is there a coupling where you can lose the excess?

Good point.

I had the leg off one of these the other week.I don't remember any way of shortening the gearchange linkage.There is a coupling but the two halves of the gearchange linkage are butted right up. However, it could be extended inside the leg where it's not visible 'til you remove the shaft extension.

howy · 23 April 2010, 07:14

Thanks for all the advice.

I think I will sell this engine on and buy myself a short shaft, it seems to be the easiest route.