2 Stroke Outboard Best Practice?

BuenaOnda said:
Hi! I’m new here (and from Belgium), please be kind with me (and some approximations in my English) ;)
I usually run the carb dry, unless I use it again in the same day. And if I forget to dry, I must admit I can’t run it easily the next day...
I was surprised nobody talk about fuel quality and ethanol share. But it seems that’s that E10 fuel (i.e. fuel with 10% ethanol instead of usual 5%) is not yet common in the United Kingdom. Right?
I must say that I have much more problems with E10 fuel, perhaps also because my engine is old (2002). As in Belgium or France you have the choice between 95E10 and 98E5 fuel, I choose the second one every time it possible.
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Welcome to the forum. Here in Portugal, I just use supermarket cheapest 95 octane, which I think is 7% bio. 50:1 2 stroke mix and will start first pull after a week or more without draining the carb.
 
Graham376 said:
Welcome to the forum. Here in Portugal, I just use supermarket cheapest 95 octane, which I think is 7% bio. 50:1 2 stroke mix and will start first pull after a week or more without draining the carb.
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Thanks Graham :giggle:
Yes, perhaps it's also linked with Normandy-style humidity. Usually, when I sail, I use the motor just to go out of the harbor in the morning, then arriving at anchor in the night, and it works well without draining the carb. But If I stay 2 days at anchor without starting the engine, 80% of the time I can't start it on the 3rd day. Ok, as I said, I have sometimes old fuel remaining and, in addition, they just have 95E10 fuel in my home port. So now I try to buy only 98E5 at the gas station in the town... And to mix it with old fuel there's still left. And I must say it goes better.
 
Like everything - there will always be variations .... drain or not drain ......

Me - may I suggest that erring on the safer side may be an idea ? Doesn't hurt to run carb dry - contrary to some doom-merchants claims ....

Stopping on the button - Im not so keen on because the engine continues to draw fuel for a few seconds while rpm subsides ... that's fuel that sits inside waiting for you ...
 
Refueler said:
Like everything - there will always be variations .... drain or not drain ......

Me - may I suggest that erring on the safer side may be an idea ? Doesn't hurt to run carb dry - contrary to some doom-merchants claims ....

Stopping on the button - Im not so keen on because the engine continues to draw fuel for a few seconds while rpm subsides ... that's fuel that sits inside waiting for you ...
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Thats correct but perhaps best to do so not high at high revs because as the quantity of fuel decreases so does the oil. idle or fast idle is OK.
The only outboards where a case can be made against running the fuel dry are the big multiple carb jobs . It is suggested that the top carbs tend to run out of fuel first then the top cylinders are being driven without any lubrication by the lower ones .... I'd not like to comment on the validity of this though.

Stopping on the button and allowing fuel to be drawn in but not burnt may not be too bad a thing... at least it contains some oil.
 
In my manual it says when leaving the engine for a while, remove the spark plug and poor in a teaspoon of engine oil, then replace.
Does anyone actually do that?
 
northcave said:
In my manual it says when leaving the engine for a while, remove the spark plug and poor in a teaspoon of engine oil, then replace.
Does anyone actually do that?
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Probably a good idea if you are using 100:1 fuel mix.

I spray a little oil in via the air intake while the motor is running and then kill it as part of the winter lay up procedure . ( I used to use "fogging oil" in a spray can until a local outboard chap suggested 2T oil in trigger spray bottle)
 
Graham376 said:
Sorry guys but reading some of the replies, I wonder if some people used to drain motor bike or (old) car carbs when leaving overnight? Seem to be a lot of unfounded worries.
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Overnight, no.
When bikes were left a long time between being used, they were frequently difficult to start.
2 Stroke mopeds were not known for their reliability. Everyone knew how to take them apart.
Outboards suffer from being used infrequently and not getting much fuel through them.
Plus they have very small jets.
And they're stored in damp places near the water.
Bikes are also less often picked up and put down on their side.
And a bike with a kick start will drag more mixture through than a pull start motor.
Electric start, even better.

You do what you like.
Generally every summer, we'll see people struggling to start their outboards.
Along with mowers, strimmers and all those noisy things.

On my old bikes, I used to turn the fuel off at the top of our road.
 
Graham376 said:
Sorry guys but reading some of the replies, I wonder if some people used to drain motor bike or (old) car carbs when leaving overnight? Seem to be a lot of unfounded worries.
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Well .... I can honestly say that all three Lambretta's .... the Villiers powered Class 1 Go-Kart .... the Puch Moped ..... Honda PC50 ..... all 2strs .... were all similar ..... easy to start when only stopped for a short while ... but 2 - 3 days later ? Different ball game ...

The big difference is that all apart from the Go-Kart ......



Were in daily use and therefore rarely left standing for long.
 
northcave said:
For example do I need to be anal about running the carb dry after each use?

Should I empty the tank entirely if leaving it laid up for more than 3 months?

What’s the best pre mix ratio?

Can I lie it down on both sides, unlike a 4 stroke?

Anything else?
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I have had one for 3 year, but don't consider myself an expert. However:

1) Not on this engine, no. I never do in spite of sporadic use and have never had any problems. I suspect the jets are larger than modern engines.
2) I never do.
3) I use 100:1. In future I'm going to try 50:1 'cos I'm fed up with having two different mixtures for the two 2 strokes in my life. My only concern with 50:1 is ease of starting and smokiness.
4) Yes, but watch the gear lever.
5) I'm about to ask a question about fuel taps, on another thread. :)
 
I was told by a outboard servicing expert (ie runs his own business) that you shouldn't run the carb dry by turning off the fuel, because the last few revs will be running without oil. He recommended always using the stop button. I've been doing this for the last couple of seasons and have never had a problem with a blocked carb.
Having said that, I can see the sense in doing it the last time you stop before a lengthy period.
 
SimonKNZ said:
I was told by a outboard servicing expert (ie runs his own business) that you shouldn't run the carb dry by turning off the fuel, because the last few revs will be running without oil. He recommended always using the stop button. I've been doing this for the last couple of seasons and have never had a problem with a blocked carb.
Having said that, I can see the sense in doing it the last time you stop before a lengthy period.
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Provided you only run it at idle speed there will be no problem.
At idle there will be plenty of excess oil that is not brnt. The engine will peter out and stop when the fuel air ratio becomes to low to run anyway before the carb is completely dry

This is the view expressed by numerous experts and professional outboard mechanics on the US outboard engine forums. Not just my personal opinion
 
SimonKNZ said:
I was told by a outboard servicing expert (ie runs his own business) that you shouldn't run the carb dry by turning off the fuel, because the last few revs will be running without oil. He recommended always using the stop button. I've been doing this for the last couple of seasons and have never had a problem with a blocked carb.
Having said that, I can see the sense in doing it the last time you stop before a lengthy period.
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I bet he loves getting all those outboard service jobs where owners say engine won't start !! Quick clean up of that gunged up carb jet and away she goes ! Easy money.
 
I must do some experiments but in previous experience, cutting off the fuel results in a lean-running increase in revs before cutting out. Will try again with low throttle
 
SimonKNZ said:
I must do some experiments but in previous experience, cutting off the fuel results in a lean-running increase in revs before cutting out. Will try again with low throttle
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Yes .. of course the revs pick up for that second or so as it leans out ...

I have engines that are from 1980's and they have been run dry stopped ..... and they are as good today as any other engine of similar age ...

Given some of the abuse we give our engines .. run dry carb is least of the worries !!!
 
Having run 2-strokes for over 60 years, I have never had a problem with gummed up carbs or bothered draining them. What I have always done is fit a small fuel filter between the tank and the carb and filtered my fuel as I fill the tank.
 
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