Flushing small 2-stoke by connecting hose-pipe?

Babylon said:
In answer to the various points made:

It is a 2006 Mercury 2.5hp 2-stroke (the cheaper one with no neutral). The online manual doesn't have any technical diagrams, so until I collect it from the engineer's I won't be able to see how to bodge any tap-water hose into the cooling system.

I don't want to haul the outboard home each time in the car, fill up a wheelie-bin and dispose of salt-water into my septic-tank (no mains drainage). There is a perfectly good storage shed at my club, so I want to simply be able to flush it in-situ. In this regard, it would also be useful to flush it bolted to the outboard-bracket on the boat by connecting (my bodged adaptor) to a pontoon water-supply, etc.

Don't want to have to remove the prop either - as long as the motor is securely bolted to a bracket, a whirring prop is no more dangerous to me than taking care to walk on the pavement rather than down the centre of a motorway.

Jon

PS: Just an extra thought (it seeming sensible for the impeller to move fresh-water through the system rather than hose-pipe pressure as such): if a short length of hose could be connected to the water-intake, wouldn't it be feasible for to just 'siphon' enough fresh water from a bucket to flush the innards?
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I dont think you will find anyway of connecting a hose !

( exploded diagrams here if you click on the appropriate serial number range: https://www.boats.net/catalog/mercury/outboard-by-hp/2-5hp )

With the waterpump behind the prop you will not need such a deep bin/bucket to run it in as you would with a model with the pump on top of the gear case but with the prop left on you will soon have no water in the bin!
 
VicS said:
I dont think you will find anyway of connecting a hose !
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As I thought, it’s like my Suzuki with water direct into the impeller case. Definitely tricky, but it might perhaps be possible to get a small rectangular flush muff into place and have some of the water go into the engine.

VicS said:
with the prop left on you will soon have no water in the bin!
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In a normal dustbin (not wheelie bin) it’s no problem to leave the prop on a 2hp, at least up to maybe 1/2 or 3/4 revs. It’s how I flush mine.

Pete
 
Although badged as a Mercury it is made by Tohatsu.

Although unlikely it is possible to force water into the engine cylinder via the exhaust port by power flushing with a hose.

I used a bucket. Much simpler all round if a little splashy. Resist the temptation to rev it unless it is OK to get wet.
 
TQA said:
Although unlikely it is possible to force water into the engine cylinder via the exhaust port by power flushing with a hose.
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I think you’d need anti-gravity water that can turn around and jump upwards inside the leg, pushing past the outgoing exhaust gas on the way.

Pete
 
Thanks for all the contributions! :)

Simplest method then is to just use a decent-sized bucket - which I can chuck into the back of the car and take that back home.

Screen Shot 2018-12-02 at 14.46.30.png

...Best take the dog out first! :D
 
RivalRedwing said:
yup, but more water stays in the bucket if you take the prop off and taking the prop off also means you can give the engine more revs & hence a more powerful flush.
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Yeah, the bucket with the dog in is probably not deep enough to keep the water in if there’s any thrust.

Pete
 
You're right Pete, but on tickover (with a hose topping it up if needed) I'm sure it'll suffice.

The key thing is that its a convenient and lightweight solution - for me.
 
Babylon said:
Is it possible to flush salt-water from a small 2-stroke outboard on dry land by just connecting a hose-pipe to the cooling intake/spigot? Would it damage the engine by there being no external water-resistance on the prop?

After a decade of flushing it in the club's tank (which is never changed and has become progressively polluted with ponging brackish water, contaminated with old fuel and oil dumped into it by lazy idiots), the cooling channels have become almost totally blocked and its costing me a small fortune to have this repaired.
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I could not find a way to do that so I made a small foldable stand with a food waste plastic container that fitted between the stand legs so it could not move. I can now flush with the prop on using only 10litres of water. I also have a 20litre old plastic oil can that fits too (but no picture of that). Ten litres of water is easier to dispose of.

https://drive.google.com/open?id=1iEpyZnsF9jFRIlk-COJzIrZj8b0EcHFt


www.solocoastalsailing.co.uk
 
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That's it! Thanks Plumb. I have a spare 10l food waste bin exactly like that, and it won't take more than an hour or so to run up a folding frame.

There's no rule that says the motor needs to be run on anything faster than idle for the salt-water to be flushed out.
 
Many Tohatsus (if not all) have a screw next to the top gearbox oil screw. A hose adapter screws into that, the water intake grills have to be covered with gaffer tape, the hose turned on and the engine started and run for a few minutes.
https://www.ebay.co.uk/itm/Mariner-...m=181535253879&_trksid=p2047675.c100008.m2219
P.S. Flushing can be done this way when engine on taffrail by gravity feed, using short hose, funnel and can of water.
 
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Neat solution, unfortunately won't work for my 2.5hp 2-stroke, as description says for:

Mercury/Mariner
4/5 hp. (1 cyl.) 2-Stroke
F2.5/3.5 hp. FourStroke
F4/5/6 FourStroke Outboards (0R411837 and below)
8/9.9 hp. FourStroke outboards (model year 2005 & newer)
 
Babylon said:
Neat solution, unfortunately won't work for my 2.5hp 2-stroke, as description says for:

Mercury/Mariner
4/5 hp. (1 cyl.) 2-Stroke
F2.5/3.5 hp. FourStroke
F4/5/6 FourStroke Outboards (0R411837 and below)
8/9.9 hp. FourStroke outboards (model year 2005 & newer)
Click to expand...

Description doesn't mention Tohatsu either but it fits my 9.8 OK. I got mine from local outboard shop and no doubt they have alternatives for different engines. Try this ebay search https://www.ebay.co.uk/sch/i.html?_...l1313&_nkw=outboard+flush+attachment&_sacat=0
 
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