Recirculating test water

TheShadow619

Cadet
Joined
May 11, 2014
Messages
27
I live in California where, some of you know, we got no rain this year. We are having a hell of a drought this year. Fortunately we do still have some lakes to play on this summer. But... my city has issued a notice of a $500 fine for running water down the sidewalk/gutter. So what I would like to know is, is there someone who sells a system for recirculating a few gallons of water for test running the engine in the driveway? Or does someone have plans on how to build one? I have a few ideas, but none of them seem real workable. I have an I/O, so with the 2 ports near the transom, the extra water from the muffs, and the water pouring out of the prop, I can't figure out a good way to contain all the water. I figure I could use a submersible pump to pump water to the muffs. Any ideas?
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,031
You would really need a large container to put under the outdrive. Now put a few gallons of water in it and use a sump pump to pump water to the flusher device. The idea is for any water out of the prop or gratings on the outdrive to fall back into the container, and be reused.

Best I can think of on 1 cup of coffee.....
 

minuteman62-64

Lieutenant
Joined
Apr 12, 2011
Messages
1,350
I'm also adapting to the California water use/runoff regs. My 30 HP single motor probably generates much less water than your rig, but, anyways, here's what I do. On the muffs I put a small kids wading pool (about 10" deep/6' diameter) under the motor, adjust the flow as low as I can and still have water coming from the tell-tale. This gives me about 15 minutes run time. Then I use a sump pump, purchased at HD, that will pump to about 1/8" water depth, to pump the water through a hose to my landscaping.

I've also run it in a barrel and picked up the tell-tale flow with a 5 gallon bucket. When done, same thing - sump pump to hose to landscaping.
 

rbh

Fleet Admiral
Joined
Mar 21, 2009
Messages
7,939
Stick the IO in a cleaned out garbage can and fill it up
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,216
Get your self a big 55 gallon plastic barrel, cut it out so the outdrive will just set inside, add enough water to get to the water inlets. Will only get you a few minutes run time, but enough for testing. Make a cover of some sort and save the water for the next test run.
 

UncleWillie

Captain
Joined
Oct 18, 2011
Messages
3,995
The problem with recirculating the water is all the heat.
The exhaust water on any engine is noticeable warmer than the water that went in.
If you return the exhaust water back to the engine; in two or three passes the water will be too hot to touch.
The engine cooling system was designed to receive fresh cool water and only pass it through the engine once.

My 6 hp OB will warm a 5 gallon bucket of water to over 100F in just a few minutes at idle.
A 100+HP engine at idle, will warm the water by 30 to 40F on each pass through the engine.
Unless your water system will hold a few hundred gallons, it will overheat quickly.
1 hp is about 750 Watts. An idling 100+hp engine could be a 5000 Watt water heater.

The Exhaust system on an I/O is Rubber and Plastic and does not tolerate high temperatures very well.
The $500 fine might start to sound cheap compared to the cost to replace a melted exhaust system.

For a short 1 to 2 minute test, attach the muffs, and park the Drive over the grass.
Recirculating the water is going to get you in thermal trouble in less than a minute.
 

TheShadow619

Cadet
Joined
May 11, 2014
Messages
27
Thanks for the input. Parking over the grass is probably the best Idea. As long as I miss the sprinkler heads with the tires. :)
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,454
Get your self a big 55 gallon plastic barrel, cut it out so the outdrive will just set inside, add enough water to get to the water inlets. Will only get you a few minutes run time, but enough for testing. Make a cover of some sort and save the water for the next test run.

Can't do that with a sterndrive that has an engine mounted raw water pump. If you have a Volvo or a Merc Bravo there is no way this will end up well. Even an OMC Cobra won't work unless you get it up to the level of the pump which would be almost impossible.
 
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