1st boat

[Mark O'Malley]

Was at a friend's neighbors house about 2 years ago and he was randomly showing us his rc car collection. Sitting on top of a bookshelf opposite side of the room sat this really cool looking vintage rc nitro boat, had a big pipe on it as well. Being a 2 stroke guy already, the tuned pipe really got my attention. He ended up offering to sell the boat to me for 60 bucks. Overall condition was questionable but the hull itself looked pretty solid.. 2 years later, I have basically replaced everything but the hull and the tray the electronics set in, and the turning strut. Engine was a .20 novarossi that ended up having no compression. I went ahead and replaced the servos and got a new spektrum radio and reciever. I ended up getting a screaming deal on a brand new in box losi mach 427 1/8th scale buggy engine. Engine makes just over 3hp at 20kish rpms. After some machining and a new collet, I was able to fit it in the boat. Had to replace the stuffing tube and flex shaft as well. To handle cooling temporarily, I installed some aluminum tubing around the air cooled head. Brand new octura x440 balanced and sharpened propeller as a starting point. Boat handles great in the water but I think I need more pitch. I work in a machine shop so I plan to make a custom water cooled head in the near future. I honestly have no idea what I'm doing with this boat so I'm kinda learning as I go.. I've been flying rc planes for about 2 years now. I do have 2 nitro planes so I do have a little experience with nitro engines.the boat is 32 inches long not including the strut. Any suggestions or tips, advice is all very much appreciated. This has been a very long project that I finally got to put in the water. What a riot it is haha.

 

[Danny King]

Awesome. Man we all started off similarly.
This is a great example of you don’t have to spend a lot to get into it. You’ll learn
Tons just from this boat.
There is something really rewarding about putting in the time and figuring it out and getting results on your own.
Welcome to the hobby!
I love the effort!!

 

[Mark O'Malley]

Thankyou sir! It's been an interesting project for sure! I'm still unsure about the carb tuning and prop selection. It's a 32 inch mono hull. The engine is a .27 I believe. Power output is around 3hp. What kind of temps should I see on the head at the glow plug after a decent run? After a hard run, I'll get a slight sizzle on the head right by the glow plug. Could you possibly give a prop recommendation? Currently have a x440 octura prop that was balanced and sharpened by ose.

 

[Danny King]

Head temp at 200 is s fine. But with a proper set up. You can run too small a prop and over heat.
I’d reach out to Mark Sholund. He does tons of props and can get you closer on that the. I can. It may take a few attempts.
I shared this post with Mark.

 

[shoboat]

Mark,

I would try an ABC 1614/3 or a 1714/3
And see how they would work. How much nitro % are you running? 30%?

Let Me Know Please,

Mark Sholund

 

[David Ashcroft]

Good boat enjoy..

 

[Mark O'Malley]

Mark,

I would try an ABC 1614/3 or a 1714/3
And see how they would work. How much nitro % are you running? 30%?

Let Me Know Please,

Mark Sholund

Thankyou for the recommendation! Do you have those 2 props available? Also, are those 3 blade props? Any reason for the 3 blade over the 2?

I am running vp fuel currently. It's a 50/50 mix of pro race 30% nitro, 9% caster and masher basher 20% nitro with 15% caster oil. The very first time I ran it which was for a few min with no more than half throttle was omega 15% that I run in my 2 nitro planes. I did that before realizing I needed more nitro content in the fuel. What do you recommend in the boats? It run a lot better with the vp fuel. I also raised the strut up about 1/8 inch on the 2nd run out. Hard to tell if it was the fuel or raising the strut up that made it have more rpm and it was definitely a little faster too.

 

[Mark O'Malley]

Good boat enjoy..

It's been a blast so far! Handles great and stays planted in the water. Definitely capable of more speed with some tuning. Which is why I'm here! Here's a little video of the maiden. Another buddy has a black jack 55 and another one has a few electric boats.thos was with the omega 15% fuel and before raising the strut. I didn't go above half throttle.

 

[David Ashcroft]

 

[Mark O'Malley]

Finally got the opportunity to design and machine a watercooled head for the engine. We'll see how it runs with the water cooled head.

 

[FloridaScaleBoater]

Nice work.
I like the exhaust coupler arrangement. I always have trouble with my pipes sliding shorter on 180* headers

 

[Mark O'Malley]

Nice work.
I like the exhaust coupler arrangement. I always have trouble with my pipes sliding shorter on 180* headers

Thankyou! That is a silicone hose from Amazon haha

 

[FloridaScaleBoater]

Thankyou! That is a silicone hose from Amazon haha

Have you run it yet?
The hose holds up to the heat?