2 stroke outboard engine fogging oil

Sailingsaves

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Never used it before: simply drained all fuel, emptied carb, 2 stroke oil squirted into cylinder

If squirted into the air intake, it will protect some parts of the carb. etc, but the bowl must surely be drained?

2) Is it ok to run the engine in antifreeze instead of freshwater to inhibit corrosion inside? Or is normal car antifreeze bad for aluminium alloys?

Mariner 2.5hp, 1995 model in mint condition, 2 stroke.

Thanks
 
Never used it before: simply drained all fuel, emptied carb, 2 stroke oil squirted into cylinder

If squirted into the air intake, it will protect some parts of the carb. etc, but the bowl must surely be drained?

2) Is it ok to run the engine in antifreeze instead of freshwater to inhibit corrosion inside? Or is normal car antifreeze bad for aluminium alloys?

Mariner 2.5hp, 1995 model in mint condition, 2 stroke.

Thanks
I used to use fogging oil but now, on the advice of my local chandler /outboard dealer, use TCW3 in a trigger spray bottle.

Not practical to drain the carb bowl of my E'rude so I disconnect the fuel line and knowing how long it will take to run out of fuel, spray in the oil to stall it at the last moment. Some fuel remains in the bowl of course but been doing that for 30 years and not needed to strip or clean the cab yet.

Car antifreezes are compatible with aluminium but unless you are going to run in antifreeze after every use no point in doing that. Small outboards drain completely if kept upright so run in fresh water and allow to drain
 
I imagine there might be some small virtue in introducing a drop of neat oil to the combustion chamber, then turning the motor over a few times with the spark plug uppermost (i.e. not in the normal running position) to lubricate the bore and rings.

As to the the rest of the engine, If you've ever stripped a healthy two-stroke, you'll know that normal running leaves everything in the bottom end coated in a lovely film of clean oil, bearings included. No need to add to it for a winter lay-up. If the engine has been dunked in the oggin in the recent past, however, it's a different matter, as some salt could be left in the main bearings, in particular. In this case a thorough wash-through with diesel is warranted.

The carb just needs to be dry. A recent thread focussed on running the engine until it ran out of fuel to achieve this, which is harmless and works, up to a point. But it's more thorough simply to drop the float bowl and make completely sure. This will also give you the chance to clean any deposits out of the bowl, where they tend to accumulate.

Running antifreeze through the engine can't do any harm, but fresh water is effective enough...and a great deal cheaper.
 
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Many thanks. I haven't used the engine for a couple of years and thought I'd treat it to a dose of the proper stuff, but it appears I haven't been too far off the mark.
cheers.
 
Hi Saikingsaves,
Mac is spot on with everything he says, I will just add that there should be a carb drain screw on the bowl of your carb to help you drain down.
Steve
 
Hi Saikingsaves,
Mac is spot on with everything he says, I will just add that there should be a carb drain screw on the bowl of your carb to help you drain down.
Steve

Hi,
Yes, that is my normal procedure, drop the bowl, wipe out, dry, re-fit, after ensuring tap is off, tan is empty etc. I squirt some 2 stroke into the cylinder and turn it over (have never grounded the spark plug which I read the other day should be done).

I have just bought some QuickSilver corrosion guard. After a freshwater rinse off, I used to spray electrics etc with something similar to wd40, but not wd40. The Quicksilver is however better (I have read and seen - it leaves a thin solid wax over everything and has corrosion inhibitor in it) whereas wd40 has been known to 'eat' rubber.

The thought with antifreeze was that freshwater removes the salt, and even if leg etc is drained, moisture inside ally could build up corrosion and I thought antifreeze would inhibit any corrosion - we use it in our cars in Summer for its anti-corrosion properties... If I can get it in there by running the engine in a bucket (with prop off), I can simply plut the leftover antifreeze back in a bottle for the next year?
 
If I can get it in there by running the engine in a bucket (with prop off), I can simply plut the leftover antifreeze back in a bottle for the next year?

With most outboards a regular bucket isn't deep enough...and if it is, then the antifoul starts to get pricey.
To the best of my knowledge no outboard manufacturer recommends it for small engines. That said, it can't do any harm.

P.S. Senior moment: I of course meant 'antifreeze' but the in-head text thingy went wonky.
 
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With most outboards a regular bucket isn't deep enough...and if it is, then the antifoul starts to get pricey.

Mine's only a 2.5 and and, indeed, an ordinary bucket is too shallow. However, the plastic waste bin that goes in a locker in the galley is perfect. Just stand on pontoon and fill from water tap and run engine. With two of us we even engage gear and spin the prop for a while - it's fine at idle with such a small engine.

SWMBO likes the fact that the waste bin gets a good clean-out as well so everyone's happy!

Richard
 
Mine's only a 2.5 and and, indeed, an ordinary bucket is too shallow. However, the plastic waste bin that goes in a locker in the galley is perfect. Just stand on pontoon and fill from water tap and run engine. With two of us we even engage gear and spin the prop for a while - it's fine at idle with such a small engine.

SWMBO likes the fact that the waste bin gets a good clean-out as well so everyone's happy!

Richard

When I used the kitchen bin for the Seagull I was in trouble for making it dirty .

so I tried the wheelie garden rubbish bin but that did not meet with approval either

DSCF0419.jpg
 
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