Fresh water flush tied into boats water system

[captainmike454]

My new 60 hp bigfoot four stroke has 2 hours on it and I have flushed it with a garden hose in the upright position at the dock 3 times now.

Has anyone tied the motor into the boats fresh water system as just hitting a switch or turning a valve would seem a lot easier and as I plan to cruise this boat and will be on the hook without dockside water I was thinking about plumbing the water system into the outboard of course taking precautions not to back feed salt cooling water into the boat but it seams like an easy install.

[Harper]

So you're talking about flushing with the motor shutdown I presume, and I gather that you're saying you would flush it with the boat/motor still in the water, motor down, as in "...in the upright position at the dock..."

I don't see any reason why you couldn't do this, but I have doubts as to its effectiveness. I have to wonder also....what kind of boat requires only a 60 hp outboard to push it, yet has such an amenity as a fresh water system?

[Solarman]

Mike, when I read his statement, I thought he meant, flushing it with the flush port and the motor tilted up, out of the water, not running.

Will wait to see, which is right.

[captainmike454]

Fresh water flush

I flush the engine at the dock with the engine up out of the water and after thinking about it I am going to put a fresh water spigot by the motor so I can hose the salt off the outside also and flush the engine away from the dock.

The boat has plenty of amenities generator, air conditioner, ice maker enclosed head , shower 32 inch flatscreen, sound system ,grille ,onboard compressed air system, fridge with freezer ,sleeps 3 , dinette for 4 , has 2 cockpits ,auto pilot , radar and I trailer it with my jeep wrangler.

Google Nimble Nomad Project

[Harper]

Okay....that's cool......
My comment about effectiveness goes to the best way to thoroughly flush is with muffs and the motor running. Opens the t-stat, and the heat helps the rinse. But it's certainly better than not doing any flush at all. I also wondered about how large a freshwater tank you have, with other demands being put on your supply. But I figure you have a handle on that, so press on!

[Harper]

And that's a very nice looking boat, Mike. Sometimes I forget that some of us are out there boating just for the sake of boating, rather than chasing elusive schools of dorado.

[Moonlighter]

Hi Captain Mike

Flushing the motor out on the water, during a trip that extends over several days by attaching a fresh water hose to the flushing port certainly won't hurt, and giving the cowl etc a wash down also will help with external corrosion and maintaining appearance etc.

My Suzuki mechanic recommends 10 minutes on the flush attachment (engine not running of course) after first giving it a similar time on the earmuffs with the engine running so that fresh water gets through the water pump and leg.

So you would want to give it a similar time on the flushing attachment, and that might or might not be an issue with how much fresh water you can spare for that particular job.

Having said all that, I don't know that you will really gain a lot more than giving it a thorough wash down and flush once the trip is over. My thought is that when you run the engine up to operating speed, the internal temperatures and volume of salt water pumping through will take out any crystallised salt or calcium deposited the previous day.

So, I think you may not actually achieve very much. But, if you can spare the extra fresh water, hey, why not!?

And, (joking) I can understand now why you got the "Bigfoot" version of that 60hp engine! You are pushing some serious weight there!!!

But it is amazing how nicely a well designed displacement hull can get along with small HP engines, and use very little fuel in the process. I see you originally had it with a 40 Honda, so, I take it that the Suzuki 60 is a recent upgrade? Propping it must have been an interesting job too?

[Solarman]

Mike, after a little thought on the matter, flushing by the flush port in upright/ tilted position should be fine, but careful washing the cover/ top of motor in same position. Water, may run down inside Cowling saturating the foam and create a number of problems with moisture inside. Even heavy rain/ showers can get water inside the Cowling when tilted up. The only ways to dry out, remove the Cowling till dry, or run the motor in the down position until the heat of operation dries it.

Best advice, spray the foot off, flush the port, and use a damp rag to wipe the Cowling. Set motor in down position during heavy rains, or cover Cowling during rains if left tilted up. After long durations of rain, I run my motors a good 20-30 mins just to evaporate moisture and condensation that builds up inside the Cowlings.

Boats are on the water, and motors are built better than ever. Moisture is going to happen, but what's the best way to limit it, control it, and prevent it from causing problems.

Good luck. Happy boating. Ralph

[Harper]

Having been in boating for a mere six years, I learn things every day. I must admit to never being exposed to the term "bigfoot," and Capt Mike's reference to such went right by me. I surmise that it has to do with pushing larger boats (pontoon boats, tugs, displacement hulls) but am still unfamiliar with what exactly makes a "bigfoot." Perhaps someone could enlighten me on the particulars that define a "bigfoot." Thanks

[artdf175]

Mike.. it is a Mercury 4 stroke product..
they come in various HP ratings.. I have the 9.9 hp as my kicker
art

[Harper]

Yeah, I found it to be a Mercury/Mariner unit, but what specifically makes it different from another 4-stroke Mercury?Mariner/Suzuki of the same horsepower? Something with the prop? The gearing? Does it run at a lower RPM range?

[artdf175]

one could possibly come up with a lot of reasons
but it probably comes down to "marketing"

(in other words- I don't really know!!)

[Moonlighter]

Usually you will find a bigger, heavier, different geared gearbox on them, sometimes they use the gearbox from the next HP bracket up the line on these engines - ie gearbox from 115 on a 70kp engine.

They are designed and intended to push heavy, slow things like houseboats and other displacement hull type vessels, so would be ideal for CaptMikes boat. You need to know what prop to use to get them to work, too.

Some people mistakenly think you can use them to overcome insufficient HP on planing boats, but it rarely works. The exception may be for cats where transom weight is critical, they may get away with a lower HP lighter Bigfoot if they are lucky.

Here is an example - it may in fact be the version than CaptMikes has:
http://suzukimarine.com.au/outboards...product/df60av

You will see that the gearbox ratio is 2.42:1 compared to 2.27:1 for the normal 60hp. Plus, the V version weighs 10kg more, which would mainly be the bigger gearbox.

If you scroll down the page on the link above you will see a performance report for twins in a houseboat.

Cheers
Grant

[Harper]

Thanks Grant. I kinda figured it would be in the gearing and prop choice, since there would seem to be a difference in how to push a displacement hull vs. a planing hull.

[captainmike454]

Bigfoot the motor not the large hairy guy running around in the woods

HI
The Suzuki dealer it came from called it a Bigfoot there are 2 models a DF50AV and a DF60AV which is the one on the boat.

There is a larger gear case and I swing a 3x14x9 prop which much bigger than the old prop and is a great improvement in getting the prop to bite in reverse which was a problem with the old Honda 40hp as the water is only a couple of inches above the cavitation plate.

There is still only a couple of hours on the outboard so it will be interesting to see the performance difference from the old 8 knot top speed.