B25 Motor well idea

[ktm_2000]

Hi Folks,

While it is cold and resin won't cure well, I am trying to plan out my project. As of now I am planning on a 300hp suzuki 30" shaft outboard for power and the outboard being installed directly on the transom. I would love a full transom but don't want to mess with a bracket. CamB25's use of a jackplate is pretty appealing but it still looks like a motor well is needed so I am looking for options which leave me with the most deck space and minimal fabrication. A plus would be a seat for the wife and kids to sit on while riding.

Here's my best idea so far, please provide suggestions on how I could make the idea better.

My idea is to re-use the old motor cover and use it for a combination motor well and rear seat. Bertram designed it with nice curved corners in the front and is already the right height for a seat. The idea would be to cut the motor cover box down so it would extend roughly 26" from the transom. A @32" wide portion of the motor box would be cut out and hinged so it could tilt forward to allow the engine to tilt. A back rest would be added to the back portion of the cutout and would hinge down as well. Material would be added to the undersides of the cut out portion to provide support for weight which would be on top.

The whole motor box would be glassed to the deck as well as the transom from the inside

In order to have items such as battery switches and fuel filters be above deck, I would create 2 interior partitions along the outsides so hoses, cables and such could come up through the deck in an enclosed space. Relatively inexpensive plastic hatches would provide access to those areas from the sides of the motor box.

Some visual's of my idea
https://photos.app.goo.gl/bhaeeCjgf1wYUvkH6
https://photos.app.goo.gl/ajV9aGxSSH2s3noo6

300 Suzuki dimensions needed
https://photos.app.goo.gl/rzm7acggvFsAkigCA

Would this work? Any suggestions to improve?

[CamB25]

I wish you lived closer to me...I would let you borrow my sawzall, but first I would make you sit down with my wife for a one on one discussion of the insanity of custom boat building!

All in good fun, of course, but you seem to be violating your own ground rules with this plan: " most deck space - minimal fabrication". Your in for a lot of fab work and the tilt box will suck up a lot of deck space. Sort of a double whammy.

If you are dead set on not using a bracket, consider eliminating the splash well all together. Cap't Bone did this and said it worked fine. I would install big scuppers in case you took one over the transom.

I used foam insulation board for mock-ups on the boat. Easy to work with and provides a quick way to get full scale mock up.

[ktm_2000]

a couple thoughts....

1. My wife already knows that I am insane
2. She has already come to terms that me spending stupid numbers of hours messing with an old boat is better than me doing even more stupid things elsewhere
3. I have an array of destruction tools in my arsenal ( notice I did not say construction tools )

[CamB25]

[John Swick]

Have you seen/heard of the 'Porta bracket' ?
www.portaproducts.com

[ktm_2000]

I'm pretty sure I do not want a bracket even though I would love a closed transom. My parking space for the boat is not too far off the road, when I parked the boat when it had I/Os my truck was in part of the street, If I put the motor 4+ feet further back I would block more of the road.

I haven't measured.... but I think the approach I've outlined will give me back some of the deck space. I would expect that I am cutting down the length of the old motor cover quite a bit. I'm thinking the max extension is going to be 30" off the transom, @ 10" of which would have been covered by the top cap.

I am going to cut out the notch in the motor cover this weekend as well as the interior partitions out of some nida core panel stock I have. I'm going to leave the motor cover full length for now and hopefully glass in the partitions using epoxy in my basement. I haven't figured out how to make the lip the movable portion will sit on yet.

[CamB25]

Matthew,

A couple of measurements from my boat that might help with your mock ups (please mock up before cutting!!):
1. The plane formed by the leading edge of the Evinrude propeller is 45" aft of my transom at neutral trim.
2. My jackplate is a 10" set back model. Bob's Machine has them in various sizes up to 14" setback
3. The point of #1 and #2, above, is you are only saving 10" by hanging the engine on the transom. (10" is big deal in some movies, but in your driveway, probably not)
4. My G2 has some set back built in due to the integrated steering system.
5. My partial splash well is approximately 18" deep as measured from the transom bump-out to the back face of the splash well. 10+ 18 = 28". Tilt on drawing is 26", so I gave myself 2" of extra space as a design margin. Suzuki similar.

Other random thoughts:
- with the jackplate I avoided cutting into the transom bump out which saved some work. You'll need to cut into the bump out to hang the Suzuki.
- I made a complete transom "module" including splashwell, livewell, and outboard seating in my garage and then installed it as one piece. Coosa and foam board. Pre-finish everything possible in your shop...much easier than on the boat. Also might be easier to toss the engine cover and make all new instead of adapting.
- Send a PM to Capt Bone to ask for his advice. He has lived through this.

I am screaming DON'T DO IT!!! as loud as possible, but I'll be glad to help in any way I can if you decide to pick up the sawz-all.

Cam

[ktm_2000]

Cam,

I'm still curious, when you jack up your jackplate to it's max height and then tilt the engine forward to the line of the original transom could you get the prop out of the water? If the answer to that question is yes, or even pretty darn close I'd go with a 14" setback jackplate in a heartbeat. I don't need the full extension of the outboard since my boat is a trailer queen but I do want the prop out of the water in case I had to switch it out in an emergency. Your pic from the other day looks like you are not far off of what I would want without the Jackplate extended.

I am only going to cut into the old I/O motor cover this weekend so no carving up the hull/top cap just yet. It still gives me an out if I change my mind. I was hoping to do some of the fabrication work indoors to get something done while it is still cold.

Matt

[Waytooslow]

Matt,

I will leave you an CAM to the math analysis.

On my B-25 I am planning to use a bracket so I cant add much to the motor well discussion. But I did recently rebuild a brand X 25' CC that was originally set up like Capt. Bones boat with an open motor well to the deck. Since I planed on dry stacking I did not want to pay for the extra length of a bracket. So I simply glassed in a 12" high by 3" wide bulkhead in front of the motor but parallel to the transom and put some drain tubes in the bottom so water in the cockpit would drain into the "motor well" . So far this has been enough to prevent swamping and gives the motor well some definition to contain the mess. Just another simple idea to consider.

Also since I have a full transom on my B-25 I am going to shorten my motor box and put seat cushions on it while still hinging to allowing access to the bilge.

FYI--The analysis for me on using a bracket was since I had to re-core the transom anyway (had to fill the holes) so the only added work was the addition of the structural knees --all of which has been completed. So now I am just down to adding the bracket which I am going to have custom built on the boat for better fitment and price. Time will tell if this plan works as planned.

I will say from personal experience that the reliability of a Bob's jackplane is impressive. I would have not hesitations about using other one then cost. I also had a porta bracket year ago and again it worked well but the price point is the same as a conventional bracket and you can't walk on it--not comfortably anyway.

[Yannis]

One other reason why the outboard needs to be completely out of the water and dry during "Up" (and not just the prop), is to prevent galvanic corrosion, especially for those keeping the boat in the water.
You don't really want your zincs to work all the time if you can avoid it.

[CamB25]

I'll give it a test when everything is hooked up, but I am skeptical about clearing the water line without a significant tilt and some lift.

[ktm_2000]

Yannis - I fully understand your point, I will not be storing the boat in the water and my thought process would be completely different if I were storing in the water.

I fish the area around cape cod, Trailering gets me a huge radius of fishing grounds and minimizes running time on the water. Our house has a boat ramp less than 1/2 mile away, which dumps into Buzzards bay which is on the south of the cape about 1/2 of my trips are out of there. The rest, I regularly trailer to cod bay North side either in Sandwich, Sesuit or Pamet river harbors as well as much further east on the south side in Bass River or Saquatucket harbor in Harwich. 12 miles per gallon on a trailer is much less expensive than 2 nmpg on the water when you start adding up the distance.

For me a tuna trip is out of Harwich and 10nm to the tip of monomoy island, then 30+ nm east from there, If I had to add the 40+ miles each way from our place to Harwich it would be time/cost prohibitive. A Bass trip is out of Sandwich and a 17nm run to Provincetown, this wouldn't be too bad if I left from our close ramp as it would only add 10nm each way.

One thought I have is that if I do a full transom, I will leave the cockpit clear and I won't have much seating on the boat, in reality only 2 spots on a leaning post. If I do my motor well / seating idea, it would give me 2 more seats albeit wet ones in rough weather.

[John F.]

Interesting discussion to follow. My 2 cents. When converting a boat to a full bracket, just be aware that it'll change the handling/ride characteristics. My B20 was converted to a transom hung outboard. It's great. Raybo has commented on here about a B20 that was converted to a bracket mounted outboard, and that his shop was converting it to a transom hung outboard because the handling characteristics of the B20 with a bracket weren't great. If you're using a bracket, you're really changing the balance and overall design from the original I/O design. My B20 floats a lot like an I/O B20, and the drive is in about the same place. So, before I went to a bracket, I'd really try to get a ride on a B25 that's been converted and see what you think. And there are a lot of different ways to do a bracket, such as a bracket that extends the running surface and provides flotation, to a bracket that basically only serves to hand the OB from. Redoing a boat is a lot of work, and it'd be just awful if after all that work the boat didn't ride well, or ride well to you.

As far as corrosion, my B20 stays in the water from about mid-April to about mid-November. The motor doesn't clear the water--part of the lower unit stays wet all year, as does the bottom of the outboard where it bolts to the transom. I haven't had any corrosion problems, and its been that way for more than a decade. And my OB is a Yamaha, which corrode.

Looking forward to following your progress.

John

[ktm_2000]

I spent some time today messing with the old engine cover and unless Cam come back and says I could use a jackplate without notching the transom I think I will go with the idea I opened up this thread with.

My boat was setup with 3.0Ls and the short engine box so I measured the box and it is 25.5" front to back and 47" wide at the top, I didn't measure at the base, it is 18" high.

I put the engine cover into the boat and found that the transom angle prevented it from sitting tight to the transom and that the center was 30" off the transom. I used a bevel gauge to determine the transom angle and then took off 3" from the bottom of both of the side panels.
side fit after 3" removed
https://photos.app.goo.gl/uCBc9s3AXKfkG9kX8

the motor box fit better but doesn't completely touch across the transom. As a seat it is quite nice, 19" to the top cap in the center and 18" to the top cap on the sides. From the transom to the front of the motor cover is 27" so it would allow me to fully raise the motor with room to spare.

I then worked on making the movable portion in the center. I didn't want the hinge to be on the top flat section and be uncomfortable to sit on so made the hinge area on the front face. To set it all up, I figured out the center line on the back then measured out 16" on both sides and made lines. I used a speed square to measure 3" down from the front face and made lines across the front face.
https://photos.app.goo.gl/mBLp3WXBggAS2XG27

The top of the motor cover was balsa cored and in poor condition. It seems that water got in there and separated the core from the panel but didn't rot the balsa. When I cut 4" off the back side of the movable portion the coring started to fall apart. Most of the balsa squares came out with gentle hand pressure, some needed some tapping with a chisel but all came off in under 15 min so none were well bonded. https://photos.app.goo.gl/wAfVx8wcstPtveE9A

I then put a set of hinges on the front to see what it looks like all together. The screws were in my junk draw, don't match, are too long and won't be the final install.
seat down
https://photos.app.goo.gl/wZcX8yLt4tV55QRY6
seat part way up
https://photos.app.goo.gl/MEip6x17L2u8bVFc7
seat fully moved forward. I'll need to put some type of chain or rope to not allow the panel to go this far forward.
https://photos.app.goo.gl/taGETr4EeeAApZrf9

I didn't get to making the interior partition panels today, I want to decore the top completely first before I make the panels. I think that I will use 3/4" nidacore for the panels and put the joint right under the cut out. I purchased some 1/4" thick fiberglass angle iron and will use that to support the top when all done.

I am quite happy in the way that this came out, there are a few things still to figure out and some fine tuning taking 1" more off the backs of the sides to make it take up a little less cockpit space but as it sits now, it seems that I will be getting back a little over 14" of deck space than when the boat had I/Os and I will get a really nice seat in the back.

[SteveM]

Here's a photo album with some B25's with motor wells similar to your design.
These are all in the Bahamas. The old guy on the Sea Fever with the Mercury is Willard Albury; owner of Albury Brothers. This was his personal boat and he did the work in his factory.
I remember him telling me a few things while I was inquiring about doing the same.

1. "Steve, I own a boat factory, you don't. It took me a long while to get it to sit just right buy laying concrete bags in the bilge".
2. "Go find a 26 Bertram with factory outboard transom, it's a better riding hull and you don't have to mess with all this".

Nonetheless. I purchased a 26, it rode great. Sold it years later and got a 31. I still admire the lines of the 25, and 20.
https://photos.app.goo.gl/6dJnemV9g9dtz8CM7

[ktm_2000]

Steve,

Thank you for the collection of B25 outboard pics. I am quite interested in how each of the boats solved the issues of less weight. There's a lot of wisdom in Willard's statement about messing with weight as in each of the images the rear chines are out of the water on all of the boats. The old 3.0L motors weighed in at about 650# a piece and a new suzuki 300 is only 650#

I am probably going to run into exactly what he is mentioning since I am taking a lot of weight out of my boat, my estimates are @750lbs. I've tried to plan out ways to add weight in the right places and offset some of the weight that I've taken out. My main fuel tank will be @140 gallons a 50 gallon increase over stock and I've shifted the tank back @16" so the extra weight would be further back in the boat. I am making provisions to have batteries back in the old motor well to help move weight further back there too. I think I am in good shape in the stern.

On the balance side, I am planning for house batteries under the front of my doghouse to help balance out. I also have the area under the drop down opened for fish boxes, weight can be added in there under the deck, what to use I'm not sure. I do know that the boat loves weight forward, I am designing the doghouse to be further forward than I had my previous center console installed.

Will I be successful? I really don't know, I will find out and the process will evolve.

[SteveM]

I never looked in the bilge or under the engine box. I suppose you could build a support under that box and lay the concrete bags there, or batteries.
Willard is not a real talkative guy. He sold the boat a few years ago. But you could call them on Man O War and see if he can offer some advice possibly.

[PeterPalmieri]

Random thought. Have you seen the older 23' Regulators? The splash well is very narrow transom - forward, guessing 12". Similar to Capt Boners boat. They use a a double piano hinged splash door that you keep up when out on the water, you fold it down when you want to tilt up the motor. Would seem to give you maximum cockpit space without needing a large well or tons of fabrication?

https://www.sportfishingmag.com/boats/b ... gulator-23

[ktm_2000]

Pete,

I get your point. One of my buddies has been tearing apart my idea based upon access to the bilge and has suggested exactly what you have.

as designed, the front of the motor well would be 27" off the front face of the transom, any hatch most likely has a 2" wide flange.

My design runs into a couple of problems:

1. I wouldn't have the space to install a bomar 15x24" aluminum hatch. There isn't enough room in front of the hatch and before the back of the fuel tank.
2. If I could install the deck hatch, I would then have a really long reach in the bilge to get at anything. Something in the back of the transom could be 30" or more inches away from the hatch. A visual would be my head stuck under the deck with one shoulder and arm trying to reach a thru-hull to adjust a hose clamp. Trying to do all this at max reach and with one hand is a recipe for frustration.

I am contemplating cutting the motor box down significantly, extending at most 6 to 10" in front of the top cap

[ktm_2000]

Last weekend I chopped off 8" more of the old motor box. I messed up the cut somewhat in that the sides are scribed to the transom angle but the top portion was not. I will have to cut 1" more off so I can scribe it to the transom.

In the end it will stick out 12" beyond the transom cap and the back of the motor box will be 20" off the transom, it should give me the ability to tilt up the motor quite a bit, obviously not 100% as the engine specs says that it needs 25" to do so.

I'm thinking that I might go with a bob's manual 5 jackplate to allow full tilt and fine tune the motor height
https://bobsmachine.com/product/bobs-ma ... jackplate/

[Waytooslow]

I would go for the bobs electric/ hydro jack plate. They are just too good not to have one. I saw a used one on THT the other day that might still be for sale.

[ktm_2000]

WaytooSlow, I'm coming over to your idea, slowly.

I did a chat session with the Bob's folks and their impression is that with their 12" or 14" setback jackplate with its 6" lift will give me enough lift to not have to notch the transom and still be able to get the prop out of the water. They did not believe that it would allow full motor tilt and that I would need to be cautious about not dinging the engine cowling. I'm wondering if one can set a trim limit on an outboard motor to prevent this

at about $1500 shipped I think this is the way to go, saves 15-20hrs of labor setting up the motor well and doing all the finishing, keeps a full transom.

Some of the labor would have to be given back, I really like how the inside of the transom is setup on outboard powered B31 which was recently posted. I think I would want to do something very similar to be able to have all the mechanicals, fuel filters, battery switches, washdown pumps, etc above deck.
https://photos.app.goo.gl/DyBrwE1FX1dkYBHk9

[John Swick]

[John Swick]

[John Swick]

<a href="http://s242.photobucket.com/user/jeswic ... 7.jpg.html" target="_blank"><img src="https://oi242.photobucket.com/albums/ff ... 091137.jpg" border="0" alt=" photo 20190320_091137.jpg"/></a>

[John Swick]

Sorry but I don't know how to resize these photos that I uploaded into my photobucket account.
I'll refer you to the rossiter boat website to see what they've done for access to the stern.
Pretty sweet set up.

[captbone]

Here is a 23 Regulator. Best of both worlds.