Benjineer's Lund S-16 Mod

[benjineer]

Hello all! It's been a while, but it's time to start modding again. I've been pretty happy with the boat, but I want to go faster, and I'm tired of holding onto the tiller. I just traded my Johnson 25 tiller (123lbs) in on a 48 remote (185lbs). It is a long shaft motor, so I have to add 5" to the transom. I'm toying with some options as pictured. One gives me a 3" thick transom, which I'm sure is overkill. I'm trying to make it as cheap as possible, and I already have plenty of 1.5 angle lying around. It's not real thick maybe 1/8", but I think doubled up inside and outside it would probably be fine. I noticed that the CMC brand angles made for this purpose at $155 are 1/2" thick and are supposed to handle a 130hp engine with no wood like I'm doing. Anything I do with wood will be covered with fiberglass resin to seal it. There is already quite a bit of extra 1/4" aluminum plate on inside and out from the previous owners attaching twin 9.9s.


The option below would probably include another angle on the inside. I would also have to build up a little between the 1/4" plates because the engine won't quite fit between them. I have some leftover diamondplate that would work for that.

This option would be extra heavy I'm sure. I'm only showing one, but it would be double 2x8s glassed to the top board. It would add 1.5" setback, which couldn't hurt. The more and more I look at it though, this seems like it might just be unnecessary. I guess I could try the above and see how sturdy it feels, then I can add the extra boards if needed. That's my current thinking.

I suppose one other option is to get a piece of 3/4" ply and use in place of the vertical 2x8s which would give me a 2-1/4" transom.

Opinions or advice?

Also, I've gotten some rotten wood on the back deck because I haven't treated this thing nicely (no cover or shed). I'm probably going to go aluminum for the deck and maybe move my console forward and add seats in front of the deck, so the whole deck can be better used for fishing. I also have an old bass boat I can scavenge some things from (steering and cables at least). This is going to be fun.

 

[Johnny]

if you go with the outside 3/4" plywood, ensure the edges
are saturated with epoxy or preservative.
- plus -
ensure the grain goes vertical and not horizontal (just for the outside piece).




.

 

[muddywaders]

Ben word of caution.I made the exact same transom extension held on with four stainless bolts with large washers.I did not realize the force pulling on the top two bolts and the nuts and washers crushed the inner skin of the transom despite having new plywood underneath.I know Lund uses a thick piece aluminum on the inside of their transoms but I would recommend another length of alum. angle horizontally on the inside through which the top bolts will go especially if the core of the transom is soft.

 

[benjineer]

Thanks, I was actually thinking the same thing. My extension angles will have 2 3/8 bolts in each side of the lower part and 2 3/8 bolts in the extension board. When I attach the motor, I'm going to at least put a backing plate of 1/8 aluminum on the inside of the new board.

It's going to be a little bit Frankenstein because I refuse to buy any more aluminum plate to get the correct size just because I have a lot of bits and pieces lying around left over from the earlier mods. It will be solid though, or I won't launch it. :idea: You know I'm kind of wondering what that old Evinrude 115 would do on here, sink or swim. It's only an extra 110 lbs, hmmm :twisted:

 

[benjineer]

Well, I got my board all sealed up, and I was all excited and ready put start putting it together. I drilled into the transom at the bottom and ended up right inside the knee braces shown above. I never even thought about it hitting there. Now I have to cut some of them out just to get a wrench in there. Nothing is ever easy.

Update: I also galled one of the 3/8 SS bolts I was using and had to cut it off. Got everything straight yesterday with my air die grinder and a carbide tree bit. Also had to remove the 1/4" aluminum plate on the inside of the transom and cut enough out on one side for the washer and nut to clear. Other side was ok. I also replaced the motor well drain as it was broken, and I added a layer of aluminum to the outside. I know I have no new pics for y'all, but I'll try to get this sewed up today and tomorrow evening, take some pics, and get the motor put on Saturday. Then I have to get the remote stuff hooked up and see how much junk I'm going to have to buy. The bass boat steering I was going to snag is froze up, but maybe I can get it loose. I haven't tried yet, just walked by and felt of it.

 

[benjineer]

Moving along.
My new helper.

I had to put the upper bolts at 1.5" down intead of the recommended 1-7/8". Otherwise, the bottom ones would have been right in the splashwell.


Something I picked up on a trade in case the old bass boat steering doesn't work.


Still not sure what I'm going to do for trim/tilt. After some cleaning and working the plunger up and down, I got the old tilt cylinder to lock in place. The gas that is supposed to be a lift assist is gone. At least it won't be jumping up in the boat with me if I hit something. I'm going to buy a factory t/t or a CMC type unit.

Update: I have a CMC PT-130 on the way.

 

[Zum]

Nice markings on your pup...I bring my 10 month old beagle with me all the time, their faces are pretty close.
O ya.... good job on the boat as well.

Sent from my SM-T350 using Tapatalk

 

[benjineer]

Nice markings on your pup...I bring my 10 month old beagle with me all the time, their faces are pretty close.
O ya.... good job on the boat as well

Thanks! We've had rabbit beagles for years, but this will be the first one to be a house pet as well. I live in town, and a pen full of howling hounds in the back yard didn't make for happy neighbors. Sire is mine and AKC heavy Black Creek and Boggy Holler breeding. Dam is my dad's that is just a good pretty rabbit dog that has never even tried to chase a deer. The kids are really enjoying "Daisy". We have an old Sheltie, but she usually doesn't want to be bothered by them.

 

[Zum]

Seems like on the same page...always had kennel hounds, normally two or three. Picked up a pup around Sept.last year and decided she would be my first house dog. Couldn't be happier with her, hunts great and never makes a mess.

first rabbit at 4 months
I had to put this one down a month ago so I only have the one.

I take the pup fishing with me, she loves watching the bass jump, she fell over board the first time out,trying to get a close look at a bass.

 

[RedHatRedNeck]

This guy is the first pure bred I've had in years. Can't wait to see how he'll do this season. Got him at Christmas at 3mo old. Already workin descent trackin at the ones behind the house.

 

[benjineer]

Those are some nice looking hounds. Hope to get her and her two brothers started this fall. My dad kept them. I'm going to give her a try on the boat also. The Sheltie has been all but banned. She barks at every cast and every splash all day long.

 

[benjineer]

Found this in an old Lund brochure.

 

[benjineer]

My 19P prop arrived today. It looks like it's never even been on a boat. Not bad for $40. My CMC tilt should be here tomorrow or Monday.
I went out to my dad's and started stripping my donor boat. Note the can of wasp spray. Only one small nest so far.

It looks like I've got some buying and selling to do. The cables that came with the motor are in good shape but ridiculously long. 16' cables up on eBay if anyone needs them. Bass boat cables can probably be used for now at least long enough for a trial, but they are a little long and are in rough shape. I'm thinking of using the folding bench seat from the bass boat. It's 40 years old, but the vinyl actually looks pretty good. It will need new boards though. What I'm not sure of is how high up I want to sit. Definitely higher than the old bass boat. I got the rotary steering off the console I acquired and found it just barely fits in my homemade aluminum console without having to move the gauges. It's almost as if I planned it that way. I'm going to go ahead and mount it and play around with seat height and and distance. My console will put the steering higher than the bass boat or the other console, so hopefully I can reach it standing without much trouble. There is no room on the console for the tach or speedo, but I have plans to make an angled panel/box to the right of the console for those and maybe a depth finder. Sorry for the lack of pics. I made a sketch of the plans but didn't photo it.

 

[benjineer]

So I got to play around with it today and take a few pics. I'm wanting to keep the steering wheel on the centerline of the boat and build storage on the right of the console. That is the plan for now.

 

[benjineer]

Still working on this thing but haven't posted in a while. I've got the console moved where I want it, and I'm framing up for the throttle. I'm going to make a recess for it, which is making this more complicated. It may look a little strange, but I didn't want a normal side console. I have the steering wheel nearly on the centerline of the boat. That way I'll have a better chance of staying dry if I get out in the choppy stuff. Someone came out with a big center console that connected to the gunnel on the right side of the boat which gave you wrap-around seating up front. This won't be that nice, but it's similar. I got the steering wheel installed, but I ordered the 20 degree bezel kit for it, since my console is a rectangular box.

 

[benjineer]

Well, I've gotten a lot done since my last post whether it looks like it or not. The CMC didn't come. I've learned my lesson about Craigslist scam artists. Stupid tax as Dave Ramsey calls it. Anyway, there will be more on that because I really do want trim. I took it for the first test run today. It did really well and was lots of fun. I tried it first with the 17p prop it came with. I got it up to about 26mph at 6000 rpm. It didn't really sound like 6000, so I need to check the tach or try another one. Brought it back in and put the new 19p on. That got it up to 30 at 5500. Verdict is that I need more prop. I know a 21 was made. I just have to scour the internet to find one.

Next steps:
1. Get the right length control cables (ordered today) and swap out this wretched control I got from the donor boat. If you are in forward gear and the engine dies, sometimes when you go to put it in neutral it slips a gear and gets hung up. Then you have to take it apart to get it to work again.
2. Finish the framing and get the rod box like I want it and carpet that.
3. The seat. Redo the folding bench from the donor boat. Get the mounting frames up for that.
4. Redo the back deck which I let rot after the last mod. It will get carpet this time.
5. Redo the front deck. Maybe change where the storage is. Also redo the trolling motor mount with wood and carpet. The metal is just too noisy.

 

[benjineer]

Brand new OEM 21P located and on the way. PN 391014 for anyone who is looking and 391015 for SS. I still don't know about the tach function. I never hit a rev limiter, which I've read should be at 6100. I think the tach said I was there. If I'm wrong, I may have just wasted money on the wrong prop. From some things I've read, the boat should run faster with the props I already have. There was no lugging or lack of power with the 19P, and if I shoved it on down at 5500, it would pick up speed quick. The tach is a '77 model Airguide 2-wire with a dial on the back for setting it. I left the dial alone as it was on a '78 Evinrude 115. Shouldn't have to change unless it was wrong on that one also. I do have another tach that came with the console I bought. I may give it a try. It is a Teleflex 3-wire that has no settings and was on a 35 hp Evinrude.

 

[murphy67]

Just made it through all 10 pages, what a great journey!! Lots of time and money and effort put into that boat, great job! Thats awesome you are converting from a tiller to a console steering, i look forward to seeing more of your progress!

 

[benjineer]

Thanks Murphy. I was just looking at yours. I saw you were running 42 with that 70. I'm sure your boat is heavier than mine. What prop pitch are you running? How does it handle at 42? That's about where I want to get to if I can keep it safe.

 

[murphy67]

Benji,
Being honest here, I have no idea on the prop pitch...its the existing prop that came on the motor from Johnson in 1988 not that I think that helps with anything..lol

Yeah I was hitting low 40's (using my water/pilot fed speedometer) with the 70, however I also "raced" my brother in my dad's 2007 Alumacraft with a 4-stroke 140 on it and my boat took the new ALumacraft out of the hole easy and I was ahead for about 150 yards or so before he took me over and he was going about 45 mph, so I know im right in the low 40mph range. I now have a GPS on my boat so Labor day weekend I will get a proper test at WOT with just me in the boat for a proper "top speed achieved"

As for handling....it handles great at WOT, as long as its not too rough...the Classic Deluxe glides on the water, but if there are whitecaps out there/too rough, I wouldn't be going full with the boat to often, where as a nice Deep-V would really cut into the wake a bit more. I think 40mph is a great speed for a smaller 16ft boat or really any boat for the lakes we have the boats on (750 acre or so, 40 ft deep, not too big/wavy) so I am just so happy that 1988 Johnson still runs like a top!!

Note: I know i can really trim my motor up a bit to and get a bit less water drag, but it adds too much bounce when it really gets up, so I usually trim it up just a bit from all the way down and its a nice median for speed, handling, bounce, etc.