Wansworth
Well-Known Member
Potencial purchase has an outboard in a well that makes getting it in and out laborious .Do I need to flush it out after every trip or can it remain for months without attention?
Flushing out outboard
- Thread starter Wansworth
- Start date
Snowgoose-1
Well-Known Member
Having a number of boats with outboard wells , have kept them in mostly for the whole sailing season without problems. Every couple of months, I lift the outboard for a cleanup and check how the anode is doing. In my neck of the woods, Trilux in the tin version does surprisingly well for both prop and leg.
I use a cut to shape childs kickboard float that I stuff in the well to stop sloshing and for possibly less drag.
Rappey
Well-Known Member
I've not really come across 25hp+ outboards that spend their whole lives on a mooring ever getting blocked waterways. It seems to be the smaller dingy engines that suffer from salt build up. It seems very bad for an outboard that is left in the down position.
ChromeDome
Well-Known Member
Before long you'll go electric and forget about flushing and weight 
Wansworth
Well-Known Member
Now there’s a thought!Before long you'll go electric and forget about flushing and weight
Chiara’s slave
Well-Known Member
We’ve got a Honda 15 on the back of the current, er, floating thing. No issues with that. The F27 we had before had a Nissan 8 in a well. Never ever took it off, flushed it at the end of each season.
VicS
Well-Known Member
My Evinrude lived on the transom bracket, only being flushed at the end of the season, without problems but it was lifted clear of the water when not in use.
If you leave it in the water it might suffer.
Perhaps you could add an additional anode to the AV plate to give extra protection. You'd certainly be well advised to inspect and replace existing anode(s) regularly and check for water ingress into the gear case.
Much will depend on the make. Some are better engineered for life in salt water than others.
Wansworth
Well-Known Member
Thanks
Dellquay13
Well-Known Member
You don’t need to flush every trip, but if you can do it after a dozen trips or so it will be plenty.
If it is too inconvenient to run the engine raised up vertically out of the water (not tilted) or ashore, you can use really well fitted Flush Muffs and a decent pressure hosepipe under the water too. You aren’t just trying to rinse out any saltwater though, you’re trying to dissolve any deposits, so the engine ought to be run for about 10mins a time. Big modern outboards (50hp+) often have freshwater hose inlets to flush without running the engine, but rare on yacht sized engines.
Dellquay13
Well-Known Member
The regularity of flushing is probably dependent on the hours run, not the number of episodes of use. I used to flush my old mobo engine every half dozen trips, but it had probably notched up another 60 hours by then (I flushed my last engine with the hose inlet after every visit tbh), but to get to that number of hours on a yacht auxiliary is going to take a lot of visits, so flushing at least at the end of a season, and maybe again at half way through is probably plenty. It’s what I do with my 1gm10 too.
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rogerthebodger
Well-Known Member
If you boat propoed boat is a sailing boat do consider the effect of an outboard causing extra drag when in the water.
[193211]
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Mariner/Mercury/Tohatsu 4/5/6hp engines have a flushing port.
My boat has an outboard in a well. Parked in a marina. Water is close by and screwing a hose into the flushing port is pretty convenient. It gets done every time I rinse the boat down.
Engine leg lifted up out of the water when left for any period of time.
Dellquay13
Well-Known Member
My Yamaha 70hp 4t has a port and gets flushed every trip, as it is so easy to do. I wasn’t aware of exactly which small outboard had adopted it, it is sensible but still not common on older engines.
[193211]
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I have a 1m length of hose with the screw in barb for the flushing port at one end and a Hozelock fitting at the other.
As you say, it’s easy to do, so it probably gets more than its fair share of flushes.
Rappey
Well-Known Member
I have a 3.5 2t. I used to run it in fresh water after every use. After some years i had to take the head off and rake out all the salt crystals as it was blocked solid.
My theory - you stop the engine, the water runs out and the damp in the waterways evapourates due to the heat of the engine leaving salty deposits which dont rinse out by the time you get to fresh water to flush.
Larger engines don't seem to suffer from not flushing although the thermostats can get blocked with salt and jelly like substance.
My diesel engine has a very clean heat exchanger after 40 years and it also has a larger than normal water flow. Larger outboards produce a larger water flow compared to small outboard. I think a more powerful flow keeps the water cooler and therfore less likely to leave deposits ?
My theory - you stop the engine, the water runs out and the damp in the waterways evapourates due to the heat of the engine leaving salty deposits which dont rinse out by the time you get to fresh water to flush.
Larger engines don't seem to suffer from not flushing although the thermostats can get blocked with salt and jelly like substance.
My diesel engine has a very clean heat exchanger after 40 years and it also has a larger than normal water flow. Larger outboards produce a larger water flow compared to small outboard. I think a more powerful flow keeps the water cooler and therfore less likely to leave deposits ?
Snowgoose-1
Well-Known Member
[193211]
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That’s 4t. I have a 2016 Mariner F6MH.
ridgy
Well-Known Member
Where is it? I have a new tohatsu 6 and was disappointed to find you can't use flush muffs with it, have to use the old bucket of water.
[193211]
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Shows it in the manual on the Mariner which is the same motor with different decals.
Underside of the power head, 12mm(?) bolt?
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Dellquay13
Well-Known Member
On bigger engines it is easy access designed to mate to hozelock type hose pipe fittings. You can be flushing minutes after securing to your pontoon berth.
