Can I change my Long Shaft to Extra Long?

Status
Not open for further replies.
Apr 29, 2012
233
Macgregor Venture 25 Council Bluffs, IA
That just sounds funny.

But I have a Yamaha 9.9 Long Shaft, at least I think it is a LS. How to tell? Is there parts available to change over to extra long? Worth the effort, or better to just buy a new motor?
 
Oct 2, 2006
1,517
Jboat J24 commack
It could be done BUT it would be very costly, for example the gearbox would have to be taken apart to install the longer shaft

They also tend to be pretty proud of there parts and charge accordingly :)
 
Feb 20, 2011
8,059
Island Packet 35 Tucson, AZ/San Carlos, MX
Measurement is taken from the cavitation plate to the inside upper part of the mounting bracket.
 
Apr 29, 2012
233
Macgregor Venture 25 Council Bluffs, IA
Thanks that helps. I just measured, mine is 23 inches from the mount to the plate that is just above the prop. I assume that is the cavitation plate. I'll get pictures.

When motoring how deep should the prop be in the water? Maybe I'm over thinking it but it seems like the motor will be to low to control very well.
 
Apr 29, 2012
233
Macgregor Venture 25 Council Bluffs, IA
It could be done BUT it would be very costly, for example the gearbox would have to be taken apart to install the longer shaft

They also tend to be pretty proud of there parts and charge accordingly :)

I'm wondering if I might find parts on Ebay. Surely someone has a bad top end and a good lower to sell. Maybe not that many extra long out there. IDK.
 
Feb 20, 2011
8,059
Island Packet 35 Tucson, AZ/San Carlos, MX
Thanks that helps. I just measured, mine is 23 inches from the mount to the plate that is just above the prop. I assume that is the cavitation plate. I'll get pictures.

When motoring how deep should the prop be in the water? Maybe I'm over thinking it but it seems like the motor will be to low to control very well.
The cav plate needs to be submerged, at the very least. Then, waves will determine how much lower than that you'll want to go with it.

As far as installing a extra-long shaft, I don't know. Have to do some researching of the manuals and machines, but it sounds like a can 'o worms...;)
 
Sep 5, 2007
689
MacGregor 26X Rochester
Also depends on where the OB is mounted, but given that it's on a V25, it's off-center. That means it came come out of the water when the boat lists. That was a problem for me with my Aquarius 7.0 (an A23 with a transom mounted rudder and off-center OB mount), with the prop coming out of the water when it got rough.

If it were me, the cavitation plate would be as deep as I could put it while still being able to tilt the engine to get the whole lower unit out of the water at the dock. That usually means the extra-long shaft version unless you don't mind reaching over the transom to control the OB. The prop being too deep may not be the most efficient, but it's a displacement hull and won't be going fast anyway.

Which doesn't answer your question (which someone already did anyway), but it gives my philosophy on using small outboards on small boats. :D
 
Apr 29, 2012
233
Macgregor Venture 25 Council Bluffs, IA
It is probably obvious that I don't know much about boat motors. First one I have ever owned. So any information you guys give is welcome.
 
Apr 29, 2012
233
Macgregor Venture 25 Council Bluffs, IA
Is there a remote shift and throttle available? Seems like I have read about some motors having that option. I could tie the motor to the rudder for turning control. Then would be able to get the prop deep and not have to bend over to run the motor.
 
Sep 5, 2007
689
MacGregor 26X Rochester
Problem with lowering the OB too much is that it can get swamped in a following sea. Not good. The extra long shaft is the better solution. From Yamaha's literature, it sounds like you have the long shaft version. They show 22.2" for the mount to cav plate on the 20 hp with 20" long shaft, and a similar couple of inches extra with the 15" version. It would follow that your 23" conforms to the 20" long-shaft version.

But if you don't have a problem with the way it performs now, then leave it.

http://www.yamahaoutboards.com/outboards/Portable/specifications
 

JerryA

.
Oct 17, 2004
549
Tanzer 29 Jeanneau Design Sandusky Bay, Lake Erie
What kind of mount?

What kind of mount do you have? Adjustable or fixed? What year is your OB? I've found items on ebay for mine, so you might find what you are looking for, if it exists. I have the 20" and an adjustable mount, and the Thruster mounted to the cavitation plate. Works well in choppy water.

JerryA
 

Attachments

Ward H

.
Nov 7, 2011
3,778
Catalina 30 Mk II Cedar Creek, Bayville NJ
I have the 2002 Yamaha 9.9 4 stroke X Long Shaft High Thrust OB.
It had the remote throttle but I found response to throttle adjustments were too slow and inaccurate. First thing I did was put the throttle back on the tiller handle.
I have the Yamaha chart which lets you figure out what OB you have, sounds like you might already have the X long shaft.
Send me an e-mail if you want a copy.
 
Oct 17, 2011
2,809
Ericson 29 Southport..
Bossman, I'm not trying to be insulting, not one bit. But if you've never torn into one of these puppies before, a pro, or another motor outright may very well be your best option..
 
Status
Not open for further replies.