Dry Land Engine Operation
Bill Bell, Kialoa, #41
If you have the original, water - jacketed exhaust pipe, you might want to try a system I have used successfully for some thirty years. It involves minor mechanical ability. What you do is to cutout a 2" bit of the 1/2" dia, soft copper pipe at the end of the water jacket that carries cooling water from the jacket into the very end of the exhaust pipe. For normal use, you replace the 2" of removed copper with a short length of vinyl tubing, pipe clamped into place. For "on the hard" operation, place your large bucket on the cabin sole or on the starboard berth platform. Run vinyl hose from the water pump inlet into the bucket. Run another length of hose from the water jacket end of the exhaust back into the bucket. Fill the bucket with clean water or antifreeze - AFTER substantial flushing of the system - and you are all set.
The surveyor who "OK'd" Kialoa for me 33 years ago suggested that an air vent at the highest spot on the block would be helpful. You can vent air from the system (to reduce corrosion when in storage) and you can solve cooling water circulation problems. I have a standard radiator "bleed valve" in a copper ell at the "front end" of my manifold that takes the water from he crossover pipe exiting the head into the entrance to the water jacket of the manifold. I think having the block FULL of anti-freeze/water mix helps reduce corrosion when in storage.
A. J. Matthews, Ay Mon, #605
Some feel that using a garden hose into the raw water inlet is a bad idea if there is any pressure in the line. It has the possibility of sending water into the cylinders and/or causing problems with the water pump. If there is no real pressure in the line, there is no problem.
I have recently installed a fresh water flush into my boat. When I am finished sailing for the day, I reach into my cockpit locker drag out a hose, turn off the raw water valve and turn on my flush valve (which is installed on top of the raw water valve). I then stick the hose onto a five gallon bucket (in the cockpit) which is fed from a hose. No pressure, no problem, just make sure the supply of water is constant.
Skip Kendrick, Sorceress, #279
I hook up a 5 gallon solar shower bag with fresh water to the raw water intake hose and run the A-4 until the bag is nearly empty; it goes slow. At least 2 minutes, maybe 5, and slow enough to react to the empty bag if you get bored watching while waiting. I read somewhere that leaving a boat setting with salt water in the block is not so good. Fresh water is better.
Jim Wyant, Tambu, #74
Dry-land operation requires you to essentially simulate the ocean - or in my case, the river!
The key is to allow the raw water pump to draw from a reservoir it its own rate (as it does from the ocean) w/o 1) forcing it to pull "up" the water any significant distance, 2) forcing water into the pump directly (i.e. with a hose) or 3) letting the pump run dry.
A large bucket in the cockpit being continuously supplied by a garden hose should do the trick. The capacity of the bucket gives you some lee-way to adjust your "make-up feed" from the garden hose to match the engine draw. Just make sure the hose you run up from the engine raw-water pump suction to the cockpit supply bucket is primed w/ water or else the pump will initially be pumping air (bad) and might not ever self-prime -- damaging or possibly destroying the impeller.
Regarding recirc - this would involve capturing the water from the exhaust gas stream below the transom and then somehow getting the water back up to your cockpit supply bucket (i.e. by pumping). DON'T try disconnecting the cooling water jumper hose at the exhaust manifold outlet! That water is necessary to cool the exhaust pipe all the way back to the transom. Unless you are in short supply of water, or otherwise can't just allow the water to dump on the ground from the exhaust outlet, this requires a much more complicated setup.