Short Shaft / Long Shaft - Telling them apart?

Pav · 26 September 2009, 13:21

Sorry for my continued novice questions, and thankyou to those with the patience to answer and not ridicule me for my lack of knowledge!

Searching for my outboard I find some people do not know if they are selling a short ot longshaft. I need a short shaft!

Google tells me all types of things thant dopn't help! Cavitation plate to Transom Clamo?!

Anyone please got a clear way I can tell if a small 3.5hp Outboard is Longshaft or short shaft when looking at it? Using terms that I will understand (prop, transom clamp and the like!)

Thankyou.

Locozodiac · 26 September 2009, 15:49

Hi,
This is a learn forum, nobody is born with knowledge, you get it while boating, so welcome to ask any out of this world tech issues not clear to you, to make it simple, this is a 20" long shaft Tohatsu 3.5 B2-L 2 stroke engine, the tail -- is 5" much longer than 15" short model. See pics for understanding.

There is also a UL 25" version, but normally used are 15" & 20 " shaft engines.

Happy Sibbing

9D280 · 28 September 2009, 09:21

Pav,

There's a post here http://rib.net/forum/showpost.php?p=249948&postcount=4 that shows it nicely.

I guess form your post that the terminology isn't helping.....

The Cav Plate ("Anti Cavitation Plate" to give it it's full & proper name, AKA "anti ventilation plate") Is the flat piece of metal that looks like two small wings above the propellor. It basically helps to prevent air from the surface being sooked in & messing up the water flow over the prop.

The transom clamps are the two hooks with hand screws that are used to fix the engine to the back of the boat. Bigger engines tend to be bolted on , as 2 handscrews cant really grip hard enough to hold the power of a larger engine, and so the "clamp" is more of a mounting plate with a couple of small hooks, which are really just there to stop it falling off when fitting it. For the sort of size you're looking at the hand screws will hold it fine.

Hope this helps.

Mercury · 29 September 2009, 10:49

Quote:

Originally Posted by Locozodiac

Hi,
This is a learn forum, nobody is born with knowledge, you get it while boating, so welcome to ask any out of this world tech issues not clear to you, to make it simple, this is a 20" long shaft Tohatsu 3.5 B2-L 2 stroke engine, the tail -- is 5" much longer than 15" short model. See pics for understanding.

There is also a UL 25" version, but normally used are 15" & 20 " shaft engines.

Happy Sibbing

Clear as mud.

9D280 · 29 September 2009, 12:06

http://rib.net/forum/showpost.php?p=249948&postcount=4

Between the lines on the pic:

15" = Short shaft
20" = Long shaft
25" = Extra long

I think this is a global standard?

jyasaki · 29 September 2009, 15:52

Spot on, 9D280.

I know that's the standard for Yam and Honda. I always assumed it was industry wide.

jky

Downhilldai · 29 September 2009, 23:11

Low hp motors tend to be 18" and 23", rather than 15" & 20"

Pav · 30 September 2009, 11:11

this is a great help. Thankyou for your contributions.
I've also found somep people refer to shortshaft as standard shaft... so it appears.

Downhilldai · 30 September 2009, 12:09

Correct term is Standard Shaft (15")
Short shaft is 12", but you won't see many of these.

AHH#pG# · 02 October 2009, 13:11

Also you can ask the seller the model plate number this may also give you the the shaft lenght
there are loads of guides on how to read a plate and get size year and length