Long shaft/short shaft - how can you tell?

Fantasie 19

Fantasie 19

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I've laboured under the impression that my venerable, but mostly loved, Yam 2 stroke was a standard shaft, it would now seem from conversation that it may actually be a long shaft... :o

How do you tell - would it give me a hint from the serial number??

P1010911.JPG
 
Measure from the underside of the transom bracket to the cavitation plate .
Standard shaft will be about 15". Long shaft will be about 20"

Some are confusingly about 17"

outboard%20shaft%20length.gif
 
Do not forget that some engines will have been converted from short to long so the only way to be sure what you have is to measure it.
 
As LS and Catalac08 have said measure it

BUT right down to the anti-ventilation plate it is likely to be a little more than the 15 or 20" which LS states

If its between 15 and 17" its a short shaft . If its between 20 and 22" its a long shaft

Very often long shaft engines can be recognised by 5" long extension piece fitted between the leg ( exhaust housing) and the gearcase

More info, including the diagram LS has posted, at www.smalloutboards.com/shaft.htm


FWIW Hondas are, i think, measured slightly differently .
 
Cheers guys- will measure it to be sure.. fairly sure it's not been modified but the tape will tell...

By the by.. I searched Google extensively, but what does the AC bit mean???

The 6EO is the model prefix - which somewhat helpfully I've found is model name 4AC.. :D

4 is clearly 4HP, the S bit I understand, the last number is just the serial, can't figure out the "AC" bit????
 
Fantasie 19 said:
Cheers guys- will measure it to be sure.. fairly sure it's not been modified but the tape will tell...

By the by.. I searched Google extensively, but what does the AC bit mean???

The 6EO is the model prefix - which somewhat helpfully I've found is model name 4AC.. :D

4 is clearly 4HP, the S bit I understand, the last number is just the serial, can't figure out the "AC" bit????
Click to expand...

Is it air cooled?
Or has it an AC lighting coil?
 
lw395 said:
Is it air cooled? Or has it an AC lighting coil?
Click to expand...

Not air cooled (got a pee stream when it runs), but I suppose it may have an AC lighting coil - no sockets on the outside I can see....

VicS said:
If it measures 17" from the inside of the bracket ( top of transom) down to the antiventilation plate its a short shaft.. see my post at #6
Click to expand...

Yup... that's what I said... ;)
 
I have a similar Yamaha to this; mine is definitely a long shaft.

If you look at the plate with the serial numbers again, under the final "A" of Yamaha there is a section where on your engine there is the letter "S". Mine has an "L" here. It could be that the letters L and S have some significance here - it might even be that there lies the hint you were seeking!

Mine is 22½" By the way, measured as per Lakesailor's diagram

Edited to add: Re-reading your original post ;-) I notice that you say "the S bit I understand" - is there some other significance to the S / L thing then?
 
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Sire said:
I have a similar Yamaha to this; mine is definitely a long shaft.

If you look at the plate with the serial numbers again, under the final "A" of Yamaha there is a section where on your engine there is the letter "S". Mine has an "L" here. It could be that the letters L and S have some significance here - it might even be that there lies the hint you were seeking!

Mine is 22½" By the way, measured as per Lakesailor's diagram

Edited to add: Re-reading your original post ;-) I notice that you say "the S bit I understand" - is there some other significance to the S / L thing then?
Click to expand...

No... as per Cliff's post above, the Short or Long refers to the shaft length.. the issue was that I still needed to measure it as someone may have extended it at some point in it's (not inconsiderable) life :)
 
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