T-Maxx Wantaby

I need help on how to build a water cooling unity for a 540 motor, mainly the pick up part of the system. I put a bigger prop on my boat for more speed but the motor quickly overheats. PLEASE HELP.

dirtman-RCU

My Feedback: (1)

UAP Napa in Canada sells 1/8 " outside diameter copper tubing. I use this to coil around moter cans and cylinder heads. It works great, especially if your cooling under pressure, like a jet pump. Any store that sells heating controls or what not, should have this tubing.

jkotlanger

I am just about to help my son build his first electric powered boat. He has already built some significant rc aircraft including a goldberg piper, gp Extra 300S and is about to start a Sig Hog bi-plane. Boats, however, are a different thing.

He heard that electric boat engines tend to get very hot and sometimes will catch fire in the enclosed bowels of a boat. Is their a motor cooling jacket available to prevent this problem and if so who makes it, is it supportable, or can I fabricate one of my own? If so how? Are their other approaches other than leaving the hatches opened.

I though about taking copper tubing wrapping it in a coil around the engine and then fiberglassing water inlet and outlet fixtures on the bottow. I figure that would create drag, but I will have drag anyhow based on the hatches being opened. Your thoughts would be appreciated.

Joe Petro

My Feedback: (1)

You can also use standard K&S brass tubing from the hobby shop.
You just have to anneal or soften it first, so that it can bend easily.

To anneal the tubing, use a propane torch to heat it enough so that it changes color, but don't heat it so much that it gets red.
You can move along a length of tubing with the torch and see the color go from natural, to sort of a blue tint.

It is then an easy matter to wind it around something.
For a motor can, I recommend winding around a form that is about 1/8 inch smaller than the motor. There are two reasons for this:
The tubing will "spring back" slightly after you wind it.
If it is slightly smaller than the motor, you can "expand" it a little, to slip on the motor, and it will clamp itself on.

Hope this helps...

Joe Petro

jkotlanger

Thanks for the explanation. I will get some copper tubing and try this out. I was thinking of using the same through hull approach that I have seen when build full size sailboats with a copper water scope facing forward so that as the boat moves forward it will push the water in and a scope facing backward for the water exhaust that will create suction and pull the water through. Does this sound feazible.

Ron Olson

My Feedback: (1)

Traxxas among others make a water cooling kit for electric motors. If you want to make your own, an old trick is to wind the tubing around a "D" cell battery. It is slightly smaller than the motor and will fit snugly when put on.

twmaster

My Feedback: (4)

Instead of copper or brass use aluminum tubing. Something like 5/32 diameter. It bends easily and is very efficient at transfering heat. Most hobby shops sell K & S brand tube in 3' lengths. Just be careful to not fold or squish the tube while wrapping. Works like a champ I make my cooling coils all the time for my small floatilla of fast electric race boats.

If you don't wanna make your own tubes Hobby-lobby, kyosho, and traxxas all sell pre-made cooling coils but they are significantly more expensive than making your own.

As for the pickup take a small piece of brass ot aluminum tube, cut the end to go into the water at a 45 degree angle, get a couple of landing gear straps and fasten the tube to the transom stick as little into the water as you can get away with. Make sure the 45 degree cut faces the front of the boat so water will get picked up easily. Drill a hole in the hull or deck to pass large diameter fuel tube through and connect inside thehull to the cooling on your motors. Drill another hole for the discharge from the cooling to exit the boat. CA or silcon the tubes where they enter/exit the hull to prevent leaks.

If building a boat buy a rudder with a water pickup built in.

Cheers,

Mike N
Twmaster

Dr.Dementia

My Feedback: (2)

If anyone is interested, I sell ready-to-install water-cooling kits for all "540", "600", and "700" electric motors for ONLY $10 per kit + postage! ($2 for 1st Class Mail / $3.85 for Priority Mail in the U.S. International is at actual cost. Insurance is extra) Each coil is wound from 5/32" aluminum tubing for maximum cooling, and each kit includes the coil, an adjustable stern-mounted pick-up tube, mounting bracket w/ screws, 1" intake and exit pipes for passing through the transom, 30" of flexible tubing, and 4" nylon wire-ties for securing all hose connections. I will happily custom-wind a coil to fit ANY motor, at absolutely no extra charge! Also available are "twin" water-cooling sets ($20 + postage) that feature coils wound as a "left" and a "right" to ease twin motor installations. At only $10 per kit, you can save yourself a lot of time and the aggravation of having to chase parts. :-) If you need one, or want more information please email me at: [email protected].

Thanks!

jkotlanger

Dr. D.
Thanks for your offer. I wish that you made it yesterday in that I purchased a coil set from Hobby Lobby. I will remember your email when I start our next boat. I see many of them in our future.

tjay88

Anyone know if conversion kits for 2 strokes are available? I want to convert 2 OS 91 DF engines for marine use but it seems OS don't make a water cooled head for this engine.

Thanks,
Tony

APA-228

My Feedback: (1)

Try looking for a "Kool-Klamp". These were made several years ago for adapting aircraft engines to boats. You see them on Ebay from time to time. Octura also made this type adapter. They looked like the bourdon tube from a pressure gauge and had a water inlet and outlet on each end. They mounted round the cylinder head and some adapters also were made to go on hte crankcase rear plate. These were held on by the reap plate mounting screws. Good Luck!

Pagemaster

Or you can try this



The ultimate in water cooling. Its a water jacket. The water comes in contact with the motor can!

Oh ya depending on the diameter, it can also be used to help cool nitro exhaust pipes.
we have them here

Steven Vaccaro
www.OffshoreElectrics.com

canadianjosh

As far as the water pick up you don't need to angle the tubing in any special way, allthough i think it would help. As for heat tranfer from the motor can to the cooling coil, go to a computer store, or radio shack, and buy some silicon heat sink paste, one brand is called Arctic Silver. Put this paste on the motor can before you put the coil on, this will give you maximum heat transfer between the case and coils. If you look with a magnifying glass you can see little striations on the motor can and copper coil, the paste helps fill these and increases the heat conductivity. If this stuff wasn't used between heat sinks and processors, then they'd all overheat and fry.

Pagemaster

If you go with the coil and heat tran grease, use shrink wrap to cove the entire thing. This will do two things, keep the grease off everthing else and tighten the coil to the motor a bit

Steven Vaccaro
www.OffshoreElectrics.com