New auxiliary motor mount for Poopsy, R21

[harry ames]

Gotta stop taking phone pix in the portrait orientation.

This is the new heavy duty auxiliary motor mount for the R21. I would hold up and elephant. I think they did a neat thing utilizing the stern molding for added stiffness. The bolts are through mounted to backup heavy duty aluminum plates on the inside of the stern. There are two plates which would allow me to mount longer or shorter shaft auxiliaries. It is mounted off center to port to assure that if I need or want to run main and the aux at the same time that the aux is in "clean" water for sucking cooling water and for the prop to work against. I'll be painting the mount burgundy or a combo of burgundy and white. Boat test in a few weeks.

 

[LAKERtoo]

.. Harry that looks simple and strong .. let me know how the test drive goes .. Cheers Rob

 

[harry ames]

I told the shop to hang onto their drawings in case someone else on Tugnuts wanted a similar arrangement. A couple of other folks have mentioned their intentions to do a kicker bracket on their tug.

 

[SGIDAVE]

Hello Harry,

That looks like a nice kicker mount. Thanks for sharing.

/dave

 

[rt11002003]

Hi Harry,

That looks like a great o/b motor mount! Do you think it will fit a R21EC? Thanks for sharing.

 

[harry ames]

Hi Harry,

That looks like a great o/b motor mount! Do you think it will fit a R21EC? Thanks for sharing.

I don't know what the factory did to the upper part of the hulls between the 21 and the EC era. From the EC pix, the area where my motor is mounted looks just the same. I really like how they took advantage of the "stiffening" rib around the outside of the stern by straddling it with the new mount. I'd have been tempted to bolt to it, but the way the shop did is is much more sound. The price is what made me happy. Custom cutting and fitting for 400 bucks and some installation labor. Not bad. I was expecting double that. Installation is a snap requiring only four holes in the hull and then some aluminum backing plates on the inside.

I don't know if the inside area of the EC hull is open enough to access the areas that the mount bolts would need for the backing plates and nuts. The Classic hull is wide open in that aft storage compartment.

 

[Stevan47]

Hi Harry: Looks great. My R21-EC is a 2009/2010 model. I have been thinking of this for mine. One questions, do you think the existing/factory-fitted swim step would be strong enough on which to mount an auxillary motor, such as yours? Also, what size/HP motor would you recommend? Interested in yours, and anyone elses', thoughts on this.

Regards, Stevan

 

[harry ames]

It really all depends on what you want the auxiliary for. I've read of a few folks who've cobbled together a swim step motor mount, but only for very small and low horsepower motors or even electrics. My motor is a 5 hp honda that is way too heavy for swim step mounting. I expect the honda to be able to push the tug about as fast as the diesel in calm conditions and to act as a second source of added hp if I have wind and waves on the nose. That is why it is mounted off center so it can be in relatively unagitated water when the diesel is also pushing. It is my poor man's way of getting a 30 hp diesel like you have in the EC.

If you are only interested in the bare minimum ability to get off the water or into a protected anchorage because of main engine failure, then almost anything will work and anything powered beats paddling. However, fate often causes engine failures during high winds and storms and current. In that case, small gas or electric auxiliaries are going to at best allow you to point into the wind and waves, but you won't make much progress.

My experiences with auxiliaries so far over many sail boats that were displacement only was that it takes little horsepower to achieve something close to hull speed in calm conditions, even 2 hp can push along a 25 foot sailboat nicely in the calm.

But to get off the water or into protected storage or into the shelter of a marina when the main fails in any real weather, 4 hp would be my minimum and there isn't any way for a boarding ladder to handle that. But as I said, a 2hp hanging on a boarding ladder is still better than paddling a tug or a C-Dory or a 25 foot sailboat.

 

[SGIDAVE]

Hi Harry: Looks great. My R21-EC is a 2009/2010 model. I have been thinking of this for mine. One questions, do you think the existing/factory-fitted swim step would be strong enough on which to mount an auxillary motor, such as yours? Also, what size/HP motor would you recommend? Interested in yours, and anyone elses', thoughts on this.

Regards, Stevan

The swim platform on my 2013 model year 21EC is quite stout. It easily supports two adults. As an alternate viewpoint to Harry's, I would see no problem with mounting a Honda 5 hp (@60 pounds) or similar unit. I would NOT trailer with the OB mounted, however, as the jostling associated with riding down the road would be unnecessarily abusive.

dave

 

[harry ames]

I misunderstood. I was thinking "swim ladder" not swim step. In that case, yes, a check with the factory would be a good idea, then a simple L shaped bracket bolted to the "step" would probably work even for a 4 or 5 hp motor. The prior poster was right that I agree a person wouldn't want to trailer any significant distance with that mounting.

 

[REO6205]

Does your motor mount have any kind of vibration damper?

 

[harry ames]

No, the motor mount is hard mounted and what the engine clamps couple to the mount will be coupled to the stern. If you look at the mount, there are two plate assemblies, one to the hull and one that carries the motor mount board. Where they meet is a place to put four vibration isolation "standoffs." However, I'm going with it the way it is as the Honda has vibration isolation of its own where the engine proper mounts to the tilt and clamp mechanism. I'm anticipating that once I get just a little warmer weather, and get the boat in the water, I'll be watching for vibration coupling to the hull. I think the Honda does a pretty good job of isolating the single cylinder chatter at low engine speeds. But that is a good question and the shop and I had that discussion and think we are good to go as is.

 

[harry ames]

I might add that this engine is a backup in case of failure of the main that would require me to get to a dock or safe shoreline. And perhaps if I'm in tight quarters and need slow turning help since I don't have the bow thruster. I've also imagined using it for extra push in case I find the little tug struggling against headwinds, but with the narrow profile of the 21, I'm thinking that it should handle headwinds just fine. Current or wave action would be another issue and more push isn't going to help in that case because of the displacement hull rules. So there will be no significant accumulation of hours to be concerned about relative to stress cracking of structural fiberglass around the engine mounting to the hull.

 

[Stevan47]

Thanks guys, for all your suggestions. I will chat to Andrew Custis at Ranger and see what their slant is on this. Kind regards, Stevan

 

[harry ames]

Got a chance to use the 5 hp Honda kicker at lake Havasu this past week. The Honda, at just under WOT pushes the R21 at 5.5 MPH. The diesel pushes the boat at 5.5 at 2500 RPM. The kicker was a life saver as the R21 will not back to port and will barely back to starboard. I just yanked the Honda rope, put the Honda in reverse, and pointed the motor in the direction I wanted to go and it worked great. If there is a lot of room behind the boat, then, throttle jockeying the diesel cab get you unparked and on your way. But the Honda just makes it so simple, and at the typical very slow trolling speeds we use on most lake fishing, it is the perfect partner to the diesel sipping two lunger for leisurely cruising. Now there may be some of you that can back a classic out of a slip space with 25 feet from the stern to the rocks, but not me.

I'm not sure that a bow thruster would have worked as well, but it could have helped. I was fighting winds blowing from starboard to port that wanted to push the boat sideways as I was backing. With the Honda, I simply went out backwards to open water 100 feet away. As I pulled back from the slip, the bow wanted immediately to swing to port due to the "sail effect" of the cabin structure, so a bow thruster might have allowed me to push it quickly around so the bow was pointing into the wind, and then the diesel would have been able to to the rest of the job.

In any case, the R21 was a hoot.

 

[daviduphoff]

This was on my 21 when I bought it. It was nothing more than a 2X4 on its side bolted straight through the swim platform with a couple straps run forward. Far from fancy but effective

 

[harry ames]

Looks effective and I like the long handle. I've got to get one of those. I purposely mounted my motor to port side of transom to put the prop in relatively clean water even with the diesel running. With my 18 hp, and in some of the winds that I see in my cruising grounds I want to see if the 5 hp Honda running at the same time will add some margin to maintaining hull speed.

I also use the Honda as my "stern thruster." That was a necessity in the tight quarters at Lake Havasu. It works very effectively as I can back out of very tight situations.

And of course, having come from owning a twin engine C-Dory cruiser, I got very use to the idea of a backup means of getting home if the main dies. In fact, all of my power boats in 50 years of boating have had a kicker and all of them were used at one time or another for emergency get home purposes.