Running it dry

[red hilux]

ive had a boat for the last 7.5 years now. I've always ran my 2 stroke dry once if flushed the engine at home.

Now, this new guy I'm using says not too. He never runs his 2 stroke dry.

What's your thoughts?

I've always done it, always been told too, now a different mechanic says not too.

 

[Mr Rum]

Did he give you a reason why?

We’ve always run ours dry before putting it away for any lengthily period of time, and we’ve had no issues.

 

[Albynsw]

I always ran two strokes dry as well. The reason I was told to do it is because the petrol evaporates and the oil left gums up the carby

 

[Outrage]

Could imagine in those last few moments when the fuel is running out it won't be getting enough lubrication and hence causing extra wear.

If it doesn't get regular use the fuel needs to be cleared though to prevent it going stale/gumming up as said. If it can't be drained out, running dry would be preferable to leaving it in there I'd expect...

 

[dno67]

The 21st century way, is to add a fuel stabilizer.
http://www.goldeagle.com.au/fuel_stabiliser.html

 

[GaryM]

The oil, in the fuel is the only lube the engine gets. It would do a fair few revolutions in the time it takes to stop, dead dry. The issues youre trying avoid are less damaging than the method. Im not sure what people expect so they can notice the effects on the day, its like smoking, it doesnt kill you first puff.

its not much different to trying to get all the oil out when doing an oil change, and running the engine for a few seconds without the filter, and oil already drained. Might keep the new oil slightly less coloured, but at what cost?

 

[Albynsw]

The 21st century way, is to add a fuel stabilizer.
http://www.goldeagle.com.au/fuel_stabiliser.html

That won't stop the petrol from evaporating though would it?

 

[GaryM]

That won't stop the petrol from evaporating though would it?

Nope. Just stops it separating and layering into its separate ingredients.

 

[dno67]

Quote''
How does STA-BIL® protect against deterioration?
STA-BIL® is a blend of scientific additives which act together to prevent fuel from degrading and oxidising during prolonged storage. STA-BIL® acts as a protective wrapper around the fuel molecules so they cannot combine with oxygen or other contaminates to corrupt the fuel. STA-BIL® ensures that all of the components that make up the fuel evaporate at the same rate so that there is little or no alteration to the composition over time.

 

[GaryM]

Ok, assuming all that scienscorcery is true (not saying it isnt), it still leaves the oil behind, and the related gum deposits. It says molecules of fuel, not droplets so I cant see how it includes the oil.

But I can tell you, I use Stabil in my 2 stroke for my brush cutter, and I have to drain the tank still. Fuel evaporates if I dont use it, and what remains gets darker and darker due to the oil mix staying put.

 

[dno67]

Treating your fuel with STA-BIL keeps it fresh for up to 12 months and stops the formation of gum and varnish deposits within the fuel system. It contains corrosion prevention additives to fight against the damaging effects of Ethanol in fuel and also cleans fuel system components such as fuel injectors and carburetors.

 

[dno67]

I don't think anything in this world is perfect..

 

[GaryM]

If nothing is perfect, isnt that a perfect record?

Love the 'upto 12 months'. Not too confident I see.

 

[dno67]

For longer storage periods e.g. 12 - 24 months:

• 60ml for every 9.5 litres of fresh fuel

For best results always store vehicles and equipment with a full tank of fuel rather than a near empty tank. Always run the engine for up to 5 minutes after adding STA-BIL® to ensure the entire fuel system is treated and not just the fuel stored in the fuel tank.

 

[red hilux]

Could imagine in those last few moments when the fuel is running out it won't be getting enough lubrication and hence causing extra wear.

Thats exactly was he said

I always ran two strokes dry as well. The reason I was told to do it is because the petrol evaporates and the oil left gums up the carby

and thats why I ran it dry.

 

[CruiserAd]

Ive had my two stroke outboard for nearly 18 years and have never run it dry, and never had an issue. Im pretty sure when you get down to the last bit of fuel it runs leaner on fuel and hotter and can cause more damage in the long run than is worth the effort.

 

[aids84]

2 stroke dirtbikes have been known to seize when run out of fuel while at full noise, the extra heat from leaning out plus the reduced lubrication would have to be the cause. Whenever I have done a top end on my bike there is always a healthy coating of oil on the crankshaft and rod. I'd imagine if you just let it idle until the carby was empty there shouldn't be any problem caused by reduced lubrication.

 

[cam04]

My smaller outboards with removable fuel hoses I always run dry - on the recommendation of my mechanic with regards varnishing of unleaded. I had a merc optimax 135 for 12 years that didn't have a removable fuel line so it never got run dry - that thing didn't miss a beat in 2500 hours. I have never run stabiliser. The difference would be injection vs carbs. It is always the carbs that varnish up from evaporation which injected motors can’t suffer from.

 

[mac_man_luke]

Had a tinny with 30hp Yamaha 2 stroke for a few years and never ran it dry, never had an issue and that was even with minimal use.

 

[Bomber2012]

Always ran mine dry .