i am planning on building a mahogany planked 40s style runabout(chris craft style), and went looking for a water cooled(that would run good enclosed in an engine hatch), and i cant find any water cooled 4 strokes...alls i can find is the offerings from honda and ryobi and theyre air cooled..anybody?

thanks,nate sanders

O.S. Engines made some water cooled glow 4-strokes. But the largest was a .61 cu.in. You can find them on the collectors market.

dang, thats it?has anyone found a way to get a lower tone from a 2 stroke?

is this just an issue that nobody really cares that much about?

hi! maybe if you could fit a honda gx31 it would be nicer, low noise and nice sound. i my self is also wating for a honda gx31 to arrive, but i still dont have a definite plan on what boat to make either a scale or a speedboat.

i was thinking about that as well, however, if it will be enclosed under an engine hatch(chris craft style), im guessing it will grossly overheat. if the head was round, it would be very possible to make a water cooling jacket to fit around it, but its more square.

4 strokes are difficult to watercool (read it from diff. posts). actualy if it is for a playboat, aircooled will be ok as long as you design the hatch so that air can freely enter and exit, that's what i've been told when i ask if its ok to run it aircooled inside a hatch. (remember i have not build yet). i agree with it though, you dont really need air rushing towards the engine since the fins on the flywheel are the once supplying the cooling air to the engine.

Here are twin marine water cooled OS .61 4 strokes in my Donzi. 2 of them running full tilt sound delicious The boat has a wet exhaust out of the transom. The gurgling exhaust out the back sound's surprisingly realistic.

Marty

marty that's a very great looking boat. have you run it already?

It is not quite done yet. I have bench tested the engines. I am still connecting servos and working out the kinks. Still need to complete some details on the deck. Need to add some scale figures, ropes etc. Just a bunch of little things to dress it up.

Marty

that is a great looking boat pusar!!whats the dimensions on the hull?

Length 49 inches Beam 13-1/2 inches Scale 3/4 in. to 1 ft. It is a big one.

Marty

Great pic's I myself am slowly building my Chris Craft Corvette with a 4 stroke engine, which is installed with twin screw operation hardware and transmisson is from MACK products.

Heck no; I'd love to have a water cooled four stroke. I have no idea why nobody makes one; seems they'd give you a bunch of torque along with the sweet sound. That would be especially sweet in 40's or 50's style runabout....there's gotta be a way to rig something up.

im glad to see its not just me, maybe the demand just isnt that high considering o.s. only made a short run of water cooled 4 strokes. ive heard about people soldering aluminum water cooling tubes onto the head or cooling fins of air cooled 4 strokes, with what success im not too sure, but its at least a thought. ive also heard of running a cooling tube through the oil reservior on hondas(that have gas and oil seperate) much like older porsches and vw's with pretty good success. the only problem with using one of these engines if height constraints, 4 strokes are pretty dang tall.

nate sanders

I have almost completed a Dumas 1930 Chris Craft mahogany and have the same request. The .60 is too tall to fit. There are .40 and smaller, but not water cooled. I did a water coolinf jacket on a 2 stroke boat and it was OK, but that is not the sound I want from this boat.
E bay had a design for a self made, 4 stroke Flat head. Perfect! But i am not up for scratch building an engine.

There is a company that makes nice scale engines, but be prepared for 8-10 grand. I won't be putting one in a lake soon.

I have just about given up and gone electric.

I wish..

good luck Mahogany Dreams.

Dave

kuhfahl:

Where there is a will, there is a way!

kmot, your links didnt work... at least not for me. also, it might be worth mention that you can turn the honda engines in any position as they have an oil slinger, and other makers have premix 4 strokes that are a little shorter than most other 4 strokes and they can also be mounted any direction.

I toyed with the idea of wrapping soft brass tubing around the fins of my Enya .46 4 stroke and maybe attaching a fan to exhaust hot air, even considered making a radiator and electric coolant pump. Electric power is so much easier and cleaner for scale models, no starting hassles, little vibration, no fire danger, no fuel/oil soak. You can even add electronic diesel or gas engine soumd.

you have never seen an electric boat catch fire???oh, and how often do you see gas boats catch fire???

Considering what's available, your 'best' bet is probably running cooling tubes around the head (fins). Or maybe if you know a good machinist that likes a challenge? Then again, I happen to have this extra Briggs/Straton 16 horse 'V'-twin just sitting here... I didn't really think so, but was worth a shot.
- 'Doc

I do not know what happened here. My photo links have never failed before.

Also, where is the "edit" button? I cannot find the edit button on my own post!! [sm=confused.gif]

Those older 4-strokes look like loads of fun!