d-lo

well, my friend just got this boat for next to nothing, it was mostly complete, but neglected, and needing lots of re-work. i am doing some of it for him, planning, making needed parts, fabbing things up, and he is doing the finish work, any glassing, prepping and painting.

so, my first question is, does anybody know what kind/make boat this is? it's all wood, by the looks of things, it looked to be a bit older of a build. the engine was in sad shape, but i did my best to get it back.......

second question, what size prop?? the engine SHOULD be fine, we will have to wait and see, but that's the size motor i'm guessing it will be running, a K&B 7.5, with a red carb, or similar......

third question, does anybody know how many turns out to get in the ballpark with that carb? the carb was seized, but i finally got it apart, cleaned up and put back together.
i am still researching, but haven't found alot of info yet. this motor is the older one, with a rotating plate for intake stroke timing, interesting setup, i must admit. i read that that is no longer used, but i am new to K&B, and don't know what year they changed.......

well, i will keep this thread updated on this new project, any tips/suggestions always welcome my way, thanks again folks........

davey

Dan S

not sure about the boat, maybe an old Prather or an old Dumas.

The motor is an older 7.5 K&B inboard,

you can find the Manual here:

http://www.mecoa.com/kb/87/9181.htm

Engine exploded view here:

http://www.mecoa.com/kb/87/9181-exp.pdf

and info about the red carb here:

http://www.mecoa.com/kb/carbs/carb35.pdf

Dan

Hydro Junkie

Good call on the Dumas. It's the 36" Dumas Atlas Van Lines kit. I can think of lots of things you would WANT to do, so here's what I'd do:
1) Scrap the hardware and put on Speedmaster or Octura
2) Pull the deck off and cut out lightening holes all through the boat
3) Move the fuel tank to under the deck on the right side beside the engine with a hatch through the bottom
4) Scrap the radio box and move it up to under the cockpit
5) Scrap the tails and wing and replace with removable framed up ones instead
6) Cut the boat in half and add 1" in the tunnel
7) Install glue blocks where ever the deck edge is glued down

Is that enough to start with?

d-lo

dan, you are the man, thank you for the links. so, it says 3 1/2 turns to start with, is that about right for anyone running one of these? i noticed there is no LSN, just a metered port in the side of the carb, do these transition from low to high speed ok?

h-junkie, holy smokes! you are a little more outgoing and talented than i am, i am probably going to be sticking to very rudimentary tasks as far as 'getting her going'. i don't know how to make a radio box, so i was going to use one from something else, if that gives you an idea of my plan. wasn't planning on any cutting her up, just enough to make it happen. good tips though, and thanks for the make and model, nice to know. if you have a suggestion on a radio box for the less 'woodworking talented', i'm all ears...........

so, anyone got a prop suggestion? i read 447 or equivalent, that sound about right? kinda newbies are going to be driving this, keep that in mind.....

thanks guys, really appreciate it......

davey

Dan S

It is quite a bit of work, if you don't feel confident just do what you can. 3 1/2 turn is a good start, correct, no LSN on the Red, Gold and Black carb. you will also need a turn fin.

for the prop I would probably go for the 445.

Dan.

Hydro Junkie

As I said, that's what I would do. Now let me give you the "what you can easily do" list:
1) Sand the boat down to bare wood and try to sharpen up the edges on the sponson(this is VERY IMPORTANT)
2) Remove the bottom of the right sponson from the transom to the first cross frame from the back of the sponson
3) Epoxy in a 3/16th ply doubler to the inside of the sponson transom. You will be installing the skid fin there later, so leave this open
4) I know this is going to sound bad, but remove the bottom between the sponsons. This is much easier to replace than the deck
5) IF you were brave enough to do #4, epoxy 1/8th" square glue blocks to the inside of the air traps even with the bottom of the cross frames and another to the back side of the internal frame on the right sponson
6) Remove the engine mounts from the engine bay. These will be replaced later with "soft mounts"
7) Again, if you were brave enough to do #4, cut lightening holes in all the underdeck framing. Leave at least 1/4" of materialon all sides
8) Run a hard copper or brass tube under the deck for the cooling line to run through or, if you prefer, just install a 1/8" ID tube under the deck and let it stick out the back and engine bay wall by about 1/2"
9) Fill all the holes in the transom with epoxy mixed with either micro balloons or colloidal silica, as well as the two screw holes on the inside of the right sponson
10) Locate where your rudder and skinfin mounting brackets will go and drill the screw holes. Over size the holes slightly and epoxy in blind nuts on the inside of the transoms, using the brackets and screws to line everything up. BE SURE THE BRACKETS ARE STRAIGHT
11) Sand the bottom of the frames flush and install a new 1/16th aircraft ply bottom, front half first. Be sure you have a building jig for this to keep the boat bottom flat. If you are going to move the radio box forward, do not get any epoxy on the frames as at least the rear one will be cut out AFTER THE EPOXY DRIES. Install a new bottom section on the right sponson at this time as well
12) Epoxy in a 3/16th" aircraft ply doubler in the rear compartment
13) Install your running gear and controls so you won't be ruining the paint job later, remove same and paint. Reinstall after the paint work is finished and go see what happens.

I'm attaching some pictures of a hydroplane the same size that I've been working on so you can actually see what I'm talking about. The solid engine mounts are going to be changed out as well. You might also recognise the engine, a K&B .45/7.5

d-lo

nice work hydro, i am mechanically inclined, mostly with metals, wiring, etc, and let me tell you, a pic is worth a thousand words! it all makes sense now, still a little more than what i may bite off, since it is not my boat, but i would love to build my own, after seeing all the wonderful makings of them. so, i am probably going to be a little more 'ghetto' in my revamping, but none the less, i will pay attention to detail, and hopefully it will serve it;s purpose, to have some fun!!!!

davey

rb110103

I have that same boat...It ran well and then I could not get the K&B 7.5 motor to run any more. I ended up replacing the K&B with an OS motor. Thanks for the tips about this boat.. anymore tips would be cool..Thanks Hydro.

Hydro Junkie

Hate to say it guys, but the boat pictured is not of the Atlas. It's actually built from downsized Newton Marine plan #108. Everything I suggested you do is or will be integrated into my boat as well. Having built the Atlas kit back in 1986 per the directions, I kinow exactly what you are working with, but I also have another advantage over you both. Back in 1988, I ran into an R/C Unlimiteds race in Marysville and, to my good fortune, met the late Troy McIntyre. Troy had tried to race the Atlas competitively and had nothing but problems. His solutions were almost exactly the same as my first posting. He explaned to me that the skid fin being on the inside of the sponson caused his to roll more often than he could count in the corners and that the boat didn't fly until he widened the tunnel an inch. The biggest thing he stressed, however, was to build a hydro as lite as possible and to try to eliminate the "fishtanks" since all boats will get water inside. Something you might look at is how heavy your boats are. I weighed mine after removing the engine, radio gear and all the hardware and found it to weigh 8 pounds. I have also weighed the boat pictured and found it, after adding a radio system as dead weight, to weigh less than 5 pounds. I'm figuring it will weigh in the 6-7 pound range if/when completed

Hydro Junkie

So, any updates d-lo?

d-lo

well, i happened upon a miss vegas, (just got her running tonight). it needed some tlc, but looks and operates great. oh, and a miss bud that i have re-vamping as well. there will be a thread for that one too, did some neat stuff to it, it's a first gen with a bunch of little mods....

so, this boat is sitting until these two get some run time, then i will clue you in!!!! thanks again for all the great info.......

davey