Home made test tank?

[crunch]

Any ideas?

I want to do a link and sinc but won't be able to put the boat in the water anytime soon... not really sure I'd want to try doing it bobbing around in the lake anyway.

Thanx in advance.

http://www.shareaproject.com/pages/projectThumbs,p276,00.html

Link dosen't work, you'll have to cut and paste to new window :'(

 

[rickdb1boat]

Re: Home made test tank?

Hi CBC

You can always run it on muffs at idle and just above. If you need to run it up, just take it to the lake and leave it on the trailer(Secured), back in the water until the lower unit is submerged and run it up. And your link still does not work when it's copy and pasted....

 

[crunch]

Re: Home made test tank?

pesky puters...

http://www.shareaproject.com/pages/projectTut,p,276,00.html

That one works if you cut and paste.

 

[studlymandingo]

Re: Home made test tank?

I have used a big plastic toolbox recently. Set it on a few concrete blocks and filled it up. Worked quite well to provide the necessary backpressure on the exhaust.

BTW: Love that vinyl the previous owner had in the boat! Where's the 'fridge?

 

[crunch]

Re: Home made test tank?

Hmmmmmmm... can't imagine much water being left in a tool box after 3 seconds with an 80 HP at full RPM !!!

 

[NBE]

Re: Home made test tank?

We used to use garbage cans in the old days. Just keep in mind that whatever you use the water will continue to get hotter and hotter while circulating through the motor and will eventually lose its cooling effect.

you can leave a water hose in the can letting it overflow and that will help with keeping the water cooler somewhat.

 

[crunch]

Re: Home made test tank?

BTW: Love that vinyl the previous owner had in the boat! Where's the 'fridge?


LOL... I'm useing it for the anchor 8)

 

[crunch]

Re: Home made test tank?

Thanx for all the suggestions so far, but I have issues with each...

I'm assuming to get the right/realistic effect of resistance on the prop, to put a load on the prop at high RPM, water would have to be shot out the back and sucked in the front... I can't see that in a garbage can.

I can see the water flow with a cross bed tool box, but I can't see much water in it if dealing with an 80 HP after a few seconds.... so.

I was driving for 5 hrs today and this crossed my mind :=

Build a frame under a 55 gal. barrel laying on it's side... cut a hole in the middle just big enough to lower prop into (thanx Mandingo), adjust height of barrel, fill with water and leave hose on (Thanx NBE)... LOL. I'd imagine you'd still get a bit of splash, but maybe enough water would remain to circulate?

I know thrust issues remain ( barrel wants to go North, boat wants to go South) but a bit of padding between sharp edges of barrel and shaft?

I really want to tune this engine before we put it in the water as wife has no desire to spend the day watching me fiddle with something she doesn't understand.... Help me out here guys...

 

[studlymandingo]

Re: Home made test tank?

The box I used was one of those job boxes by contico. Pretty darn big!!! The drum idea sounds feasible as well.

 

[Kevin W]

Re: Home made test tank?

i use a 55gal plastic drum.
Not a trash can.
it's a 55gal plastic chemical barrel that i cut the top off with a sawzall.
it held carwash soap.
i can't handle WOT.
my 70hp at about 2500rpm empties it enough for cooling to suck air.
It does work very good for idle and slightly above.

 

[Chris1956]

Re: Home made test tank?

Crunch, I saw a test tank at a OB shop. It was cement block(3'X5'??), plastered to make it water resistant. It had a place on the end to clamp on the motor and "slot" to allow the lU to be lowered it into the tank. Then a cover was put over the slot to keep th water in the tank. It was a bit permanent for my tastes. Maybe you could design one that could double as one of those permanent B-B-Qs.dd, or maybe a bait tank.8)

 

[briannh1234]

Re: Home made test tank?

The key here is not just the tank. You need a test wheel. It's a special prop that will put the load on the engine but not send the water in any particular direction. I have heard of them but never seen one myself. I assume some blades would be backwards or something.

- Brian

 

[crunch]

Re: Home made test tank?

I was just reading some posts and saw an answer from Bob VT, he suggested reading the post on link and sinc in FAQ.... according to that document I don't have to run the engine at WOT in gear to link and sinc, is that true for a 1978 Merc 800? Maybe I don't need anything more than a clean garbage can...

 

[Chris1956]

Re: Home made test tank?

Crunch, People set the WOT spark advance with the motor not running. However, I had thought you wanted the thrill of zooming across the water with the wind in your hair and a timing light in your hand.

 

[crunch]

Re: Home made test tank?

Crunch, People set the WOT spark advance with the motor not running. However, I had thought you wanted the thrill of zooming across the water with the wind in your hair and a timing light in your hand.

Uhhhhh...no.

The Seloc manual says you time them at WOT with engine running and in gear... I should have known better, that Seloc manual is about as useful as tits on a bacon rind.