Shifting from forward to reverse

I was recently test driving a 260 Searay Sundancer on the Mississippi river when the owner showed me how needs to dock his boat because of the current in the river. So he cruising fairly good when he enters his slip and then he throws it in reverse to prevent hitting the front. To me that doesn't seem to be a good practice for the motor and transmission. He has had this boat for 14 years and says he hasn't had any problems. Do I need to be concerned about the transmission and stern drive? Thanks for your help

Ayuh,..... Boats don't have brakes, so shiftin' to the opposite direction of thrust is standard operatin' procedure,.....

Sometimes you have to improvise!

Jeff

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dwgman55318 said:

I was recently test driving a 260 Searay Sundancer on the Mississippi river when the owner showed me how needs to dock his boat because of the current in the river. So he cruising fairly good when he enters his slip and then he throws it in reverse to prevent hitting the front. To me that doesn't seem to be a good practice for the motor and transmission.
The Engine will not care. It will only sense a load interruption followed by another quick load.
What may care would be the gear engagement system if the speed is "fairly good" (as you say), and if he "throws it into reverse" (as you say).

If it's a Merc A drive, and if he is not allowing the SI/SA system to do it's job (lower rpm for the shift)..... the Dog Clutch engagement teeth will certainly care.
If it's a Merc B drive or a VP drive, the sliding sleeve and gear cup will not release (from the previous gear selection) until the load lightens up.
However, a higher-than-idle-speed "slam" into the opposite gear is not a good thing!


He has had this boat for 14 years and says he hasn't had any problems. Do I need to be concerned about the transmission and stern drive?
Well..... you mention "transmission"..... which drive is it?
If A drive Dog Clutch, perhaps pull the prop shaft bearing carrier and examine the dog clutch sliding sleeve.
If A drive...... the worst case may be that you'd be replacing the lower gear unit some day.

Thanks for your help

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If he hasn't broke it yet after 14 years, it's all good.

No F^cking fancy stupid over complicated explanation needed.

And hopefully you can figure out what a A and B and VP, SI, SA are and I bet a paycheck you wont be examining anything inside the drive unit...

If you like the boat and the price is right.............go for it!

A 260 (I assume a 26 ft) then it either has two small blocks, two big block or one big block. Not knowing the actual year of the boat but considering what year it is now, I would say it has either one or two Bravo drives. Either Bravo I, II or III.

I would suggest getting a better understanding of what you are looking at before buying.

Very few boats with outdrives have transmissions.

A boat with an outdrive, The outdrive is the transmission so to speak. It shifts inside the drive itself by way of a cable system from the control box/shifter handle and there are two mechanical methods of how its shifts internal to the drive depending on the drive.

Alpha uses on method, Bravo's use a different method. Both accomplish the same goal. forward, neutral and reverse.

One other thing to remember, shifting can be done from around 1000 rpm (higher on occasion but not often and only in an emergency like hitting something) with no damage. Normal shifting occurs at the specification 650-750 rpm. The lower, the better for the drive.

Inboard boats, boats with a long stainless steel shaft that exits the boat through the bottom of the boat aft of the engine will have a transmission, it will be mounted to the back of the engine similar to an auto. it again only has forward, neutral and reverse. if this is the type of system this boat has and it may have two, then shifting at higher than normal rpm will not bother it as much as a outdrive. The way a transmission functions (internal parts) is far more tolerant of higher rpm.

Its all a matter of technique and timing. Practice shifting in the open water with the same water current conditions you will get the feel for it. A good deck hand with a spring line at the bow can tie it off as soon as the boat stops and when it starts going backwards the spring line will hold the boat up tight to the dock so you can fix a stern line.

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dwgman55318 post #1 said:

................ To me that doesn't seem to be a good practice for the motor and transmission. He has had this boat for 14 years and says he hasn't had any problems. Do I need to be concerned about the transmission and stern drive? Thanks for your help

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If he hasn't broke it yet after 14 years, it's all good.
I would like to see what your crystal ball says!

No F^cking fancy stupid over complicated explanation needed.
Perhaps you could explain why that does not apply to your post #5, yet it bothers you regarding my post. Please enlighten us!

And hopefully you can figure out what a A and B and VP, SI, SA are and I bet a paycheck you wont be examining anything inside the drive unit...
I'm sorry Jack..... but I figured that it would be fairly clear in context.
A = Alpha drive, B = Bravo drive, VP = Volvo Penta, SI = Shift Interrupt and SA = Shift Assist.

If you like the boat and the price is right.............go for it!
Agree..... if the price is right, the worst case scenario may be that it would eventually need stern drive repair.

A 260 (I assume a 26 ft) then it either has two small blocks, two big block or one big block. Not knowing the actual year of the boat but considering what year it is now, I would say it has either one or two Bravo drives. Either Bravo I, II or III.
Again, I would like to see what your crystal ball says!
Perhaps read post #1 again.
dwgman55318 (the OP) is using the singular version of "motor", "transmission" and "stern drive"!


I would suggest getting a better understanding of what you are looking at before buying.
I fully agree!

Very few boats with outdrives have transmissions.
Not quite true. The AQ series VP (that's Volvo Penta for you, Jack) upper gear units are referred to as transmissions.
Since dwgman55318 did not mention what engine/drive combo the boat is equipped with, I posed the question in post #4.

A boat with an outdrive, The outdrive is the transmission so to speak.
If broken down into 2 or 3 components, the portion where the gear selection occurs would be the transmission.
(see above)

It shifts inside the drive itself by way of a cable system from the control box/shifter handle and there are two mechanical methods of how its shifts internal to the drive depending on the drive.

Alpha uses on method, Bravo's use a different method. Both accomplish the same goal. forward, neutral and reverse.

One other thing to remember, shifting can be done from around 1000 rpm (higher on occasion but not often and only in an emergency like hitting something) with no damage. Normal shifting occurs at the specification 650-750 rpm. The lower, the better for the drive.
I believe that this is dwgman55318's concern, and is his reason for this thread.

Inboard boats, boats with a long stainless steel shaft that exits the boat through the bottom of the boat aft of the engine will have a transmission, it will be mounted to the back of the engine similar to an auto. it again only has forward, neutral and reverse. if this is the type of system this boat has and it may have two, then shifting at higher than normal rpm will not bother it as much as a outdrive. The way a transmission functions (internal parts) is far more tolerant of higher rpm.
Perhaps read post #1 again........... dwgman55318 refers to "stern drive"!

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WTF

he seems not to fully understand much........let him reply before adding unneeded over written opinion

Shifting into reverse is not a thing even if it's done quickly and you go right to wide open reverse. That's cz the thing WON"T SHIFT if it's under high engine load. You have to throttle down, pass thru neutral, then throttle up in reverse.
As you might imagine, a prop doesn't work very well spinning backwards. So it is likely that due to the current and other forces, the operator has to use reverse with high engine speed to be effective with reverse thrust. Stopping or slowing a heavy boat in a short distance takes a lot of oomph! It may seem like it's too much but there's not much chance anything will break. In fact the only thing different about going in reverse and going forward is the position of the final drive gear in the bottom (the bulge in front of the prop). It has two gears. When it's slid forward the prop spins normally. When you slide it back the other gear engages and the prop spins in reverse.
Remember a boat has to make a hole in the water. That water has weight. Imagine trying to push a swimming pool's worth of water around. That's what a boat has to do!

It's even worse if you're running a stainless of bronze prop. Every try lifting one of those! An aluminum prop reversed direction with a lot less stress on the drive system.

Jeff