Bathtub Nitro

[Capt Vic]

I read an article in rc modeler about test running a nitro boat in a rubbermaid tub. Does anyone know how this is done? I can't really get a picture in my head ! Should I make a stand for just the engine (K&B 7.5 outboard) or do I try to secure the boat???
I need some tub time to prove out a couple of modifications I made before I go to the water! Any suggestions would be nice!

Capt Vic

[Twmaster]

Tether the boat. Think of it as a leash.

Mike N
Twmaster

[Capt Vic]

I could attach the leash to the water pickup tube , and that would put the stress on the outboard and not the transom . or maybe make a stand that would support the hull and clamp firmly to the skeg to take the stress while controlling the boat! It would be a dedicated run tank but I can see the advantage of being able to run the engine long enough to warmup and set the carburator, or check for vibrations from the prop or flex cable.
I think I'll put this into the R&D stage tommorow!!

Thanks
Capt Vic

[hpiguy]

I have broken in R/C boat engines using my R/C 12V electric fuel pump.

Put the intake end of the pump in a tub of water and the output hose on the cylinder head water input.

Presto, instant water cooler when you flpi the switch.

A constant supply of fresh cold water for the engine, and no fear of flameouts in the widdle of the lake.

[Capt Vic]

That's a good idea hpiguy! But the owners manual says for maximun life of the propeller shaft bushing do not operate engine out of water for more than 30 to 45 seconds. I get the idea that that their using the water to help cool the flex shaft and prop bushing. I also would like a load on my engine to tune the higher rpm. Running the prop out of water wouldn't give me that load.

Capt Vic

[hpiguy]

Then you can buy a 20 foot piece of cheap aquarium airline tubing and a tether for the boat.

Tether the boat to the shore with a small size rope, turn on the water pump to cool the engine and then fire off the boat and let it run facing away from shore on the end of the tether.

That would work just fine also.

The pump can push that amount of water easily and still cool the engine. 20 ft if air tubing costs about $1.99.

I have friends that do this, and you could also use this technique in a bathtub, just use a boat anchor in the tub and tie the boat to it. It's pretty simple really.

[RaiderFootbal27]

no, this is how i did it, i put my boat on a stand outside, out of the water, u take a regular water bottle, u make a hole in the cap, and u stick a ball needle in it, then u take the tube that gets the water to cool the engine, and u stick the needle in it, and turn the bottle over, so the needle is facing down, and make a hole in the back of the bottle, and when the engine runs out of the water it will get its water cooling, cause it will get the water as it needs it, it really works, this is how i broke my engine in without taking it to the lake, let me know how this turns out, thanks, my email address is Iverson3_Sxrs@hotmail.com

[hpiguy]

Raider, I'm sure you technique works fine, even though it provides ZERO tension on the prop meaning the engine can easily overrev and seize being out of the water.

But regardless of who's technique he uses YOU do not start a reply by saying "NO, THIS IS HOW YOU DO IT."

That inplies that I am wrong (I wasn't, I mearly gave a different way of working things) and that YOUR idea is the ONLY way to do things.

That's rude and insulting and shows a huge lack of etiquette on your part. :mad:

[Flight]

haha.. create a little dyno out of it.. go get yourself a digital fish scale and tie it to one end of the boat.. hit the gas, tweak it and see what settings make the most torque

[RaiderFootbal27]

hey, hpiguy, chill out, take a chill pill or something, i didn't mean it by the only way, and i also didn't mean it by tuning the engine, i meant it by breaking it in, cause when it says to break it in full throtle the whole time, its hard to do that in water, so thats one of the way i was suggesting

[mbjunkie2001]

im probably wrong but wouldn't running a motor without water be like a car with no radiator? just wondering.

[RaiderFootbal27]

yes, but what u do, is u hook up a water bottle to the hole thats supposed to be picking up water when it runs, and thats the way u cool it

[HyperBaja]

you guys are much more complicate than me, i put the engine and radio in then fill the tub. drop the boat in, start it and hold the front while giving gas.

[RaiderFootbal27]

just a little question, do u do this inside or outside?

[HyperBaja]

i have done it inside and in my hot tub on the deck.

[RaiderFootbal27]

inside is not good, the gas can kill u if u do it too long, i understand for couple seconds, i start my touring car in the basement not for more then 10 seconds, cause sometimes i need to know if it starts or not.

[HyperBaja]

bathtubs are normally in bathrooms which have fans. the same fan u turn on after a ****. turn on this fan.

[RaiderFootbal27]

still...it not fast enough to get all the smell out from the nitro engine.

[HyperBaja]

if he means, starting it and running a few tank fulls through, dont do it inside. i thought he meant just starting it up.

[hunter59182]

why not try puting your boat on shore and have the back of it and
the water pickup in the water.

[Propjockey]

Here's another idea--you can pick up a galvanized tub from your local farm/ranch supply, 5' dia and 18" deep for about $30-$40 to use for a 'static test pond'. If that's too pricey, try a childs swimming pool from Wal-Mart--about the same dimensions....$6.

[Dirt Dummy]

Just put in the pond and run it! Has always worked for me. :D

[aamick1971]

This is how i broke in my 2-3.5 K&Bs, first I unhooked the water pickup from the head, then I added about 20" of fuel line to the head. Next take a 20 oz. coke bottle or something of the type put in the cap the same set up as you would do the top of your fuel can (if you are using a hand crankfuel pump)then add the other end of the 20" line to it. As you squeeze the bottle, water should flow through the head and out the other side. before cranking the motor add another basin of water to the foot of the motor. Take a 2liter bottle cut the bottom off of it leaving enough for the foot to set down in it. Fill it so that enough water comes up above to about the fourth hole in the lower unit(if needed have extra water setting aside to put in the bowl).Always be sure you have your boat setting in its stand sercurly so it won't come out or off the stand when you fire up your motor.This so far has worked for me ,and I haven't had any problems with any of my motors.This may or maynot be the best way to do this ,but it beats having to go to a pond or lake.

[aamick1971]

This is how i broke in my 2-3.5 K&Bs, first I unhooked the water pickup from the head, then I added about 20" of fuel line to the head. Next take a 20 oz. coke bottle or something of the type put in the cap the same set up as you would do the top of your fuel can (if you are using a hand crankfuel pump)then add the other end of the 20" line to it. As you squeeze the bottle, water should flow through the head and out the other side. before cranking the motor add another basin of water to the foot of the motor. Take a 2liter bottle cut the bottom off of it leaving enough for the foot to set down in it. Fill it so that enough water comes up above to about the fourth hole in the lower unit(if needed have extra water setting aside to put in the bowl).Always be sure you have your boat setting in its stand sercurly so it won't come out or off the stand when you fire up your motor.This so far has worked for me ,and I haven't had any problems with any of my motors.This may or maynot be the best way to do this ,but it beats having to go to a pond or lake.

[daniel hallman]

Bought a big oblong plastic storage container like you'd store clothes in, they come with a pop down lid. Nothing fancy, abought eight bucks at Wally World. Next thing was the cooling water supply, big old five gallon water can from some old jobsite somewhere, drilled a small hole thru the bottom and shoved the hose up inside and siliconed around it so it wouldn't slip out. To keep my Miss Budweiser from jumping out of the tub I took three old bungee cords and drilled holes in the top edge of the tub and streched the cords across the tub. All that I have to do is fill up the tub and watercan and I'm ready to drive the neighborhood totally crazy( I wear shooting ear muffs ). Where the sponsons hit the front of the tub I just hot glued some soft sponge rubber so that the tips wouldn't get messed up. You just sit the tub on the ground and the water can on an old stool , drop your boat in the tub, hook up the tubeing to the water inlet and you're ready to tune up, break in or like I said earlier, drive the neighbors crazy!!!!!! BTW, the lid from the tub makes a good work area if you'll just flip it upsidedown, the curled edges keep the little tiny things from just vanishing into thin air. It's just whatever works right for the given situation, there will always be more than one way to do something. :cool: :cool: :cool: :cool: