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Andymackk
09-07-14, 20:13 PM
With all the 2 stroke machines I have had to date ( strimmer, chainsaw etc) - they have the fuel and oil mixed in the tank. I would always shake the machine to remix the fuel and oil still in it, before I started it up. Obviously this is not going to happen with a 2 stroke trike. Does the fuel /oil separate if left sitting for a while, and what's the options to avoid it? ( And no Jim - buying a 4 stroke is not an acceptable answer :rolling: )

renmure
09-07-14, 21:26 PM
( And no Jim - buying a 4 stroke is not an acceptable answer :rolling: )

Haha :)

That would have been my only contribution to this technical subject re 2-stroke engines.
Mind you, I think I am on my 3rd strimmer and 2nd Chainsaw ... makes ya wonder eh!! ;-)

Andymackk
09-07-14, 21:27 PM
you need to learn to shake yer shammy :-)

renmure
09-07-14, 21:49 PM
Nooooo. I think they are just designed to break every now and again.



















But don't let that worry ya tho

MadamBreakneck
10-07-14, 16:43 PM
Answer: no, but the fuel loses octane rating and also becomes oilier over time as the more expensive bits evaporate off.
Options to avoid: fly more often.

Best is to mix outside the tank - we usually put the dose of oil in the Jerry can before filling with fuel.
Joan

I think my comment is correct, but best check with someone who really knows.

Rog
10-07-14, 20:18 PM
Answer: no, but the fuel loses octane rating and also becomes oilier over time as the more expensive bits evaporate off.
Options to avoid: fly more often.

Best is to mix outside the tank - we usually put the dose of oil in the Jerry can before filling with fuel.
Joan

I think my comment is correct, but best check with someone who really knows.

if your looking for a 582 then you can get them with the seperate oil system, problem solved ?

and how very dare you renmure :-D

LorraineD
11-07-14, 09:01 AM
With all the 2 stroke machines I have had to date ( strimmer, chainsaw etc) - they have the fuel and oil mixed in the tank. I would always shake the machine to remix the fuel and oil still in it, before I started it up. Obviously this is not going to happen with a 2 stroke trike. Does the fuel /oil separate if left sitting for a while, and what's the options to avoid it? ( And no Jim - buying a 4 stroke is not an acceptable answer :rolling: )

Andy, Re shaking the trike - you could always "Set phasers tae malky".

On my second 2 stroke aircraft now and dosing the can plus a good shake has been the way forward for me. I bought a nifty 2 Stroke oil measuring jug from Sthil to ensure accuracy.

WIth my 462 Q i used to find that if I had not flown for a couple of weeks there would be "goo" sitting in the float chamber where the fuel had evaporated off. Joan suggests the perfect cure for that - fly more often!

Roger Mole
11-07-14, 10:43 AM
You don't need to get too paranoid over 2-stroke fuel/oil ratios. Measuring using the marks on the side of a plastic litre oil container is quite adequate - you don't need to work to that high a level of accuracy. I fill up to the 900 ml mark from my bulk container and that gives me two lots of 400 ml between the marks. So long as you are sensible and take care to end up with the oil level on the appropriate marks you will be OK. You are not dealing with ultra-sensitive, high precision devices here - there is always residual oil sloshing around inside the engine. How do I know this? Someone I know who thought he knew better confused the little oil container for the butterfly valve lub oil on a 582 with an oil injection system (I know, don't ask...) and advised the new owner of the aircraft to top the tank up with neat mogas and fly it home, a flight of about an hour. He did so with no ill effects. The tank was subsequently filled with 50:1 and the aircraft flew safely for many more hours before being sold off to a new owner.

Andymackk
11-07-14, 11:10 AM
I think this has gone a bit sideways - :-) Actually mixing the fuel and oil in the can wasn't the issue - it was if the fuel tank on the trike was half full, and it was 3 or 4 weeks before it was used again, would the ready mixed fuel and oil separate?. Obviously shaking the whole trike isn't an option to mix it up, I was just interested to know if it could cause any issues. Although setting the Phasers to MALKY, does sound attractive regardless :hammerdrill:

LorraineD
11-07-14, 13:24 PM
Andy, a more to the point reply then. My old 462 Q used to fairly regularly sit with a half full tank for a few weeks at a time. Never any issue other than fuel evaporating off the float bowl which left "goo". Current 582 X Air also usually sits at least a week, sometimes two and more with no ill effects. In both cases I usually add another 20 litres or so of fresh fuel before I fly.

Roger, yes, accuracy not paramount but you have never seen me "mong it" with numbers - that's the real reason I need to be an oil pedant!

Andy, Off topic I know but Da's pet name for us as kids was "See you, I'll skite ye wan so help ma bob!" He never did though - soft at heart!

Proud to be the daughter of a "sweaty sock" :neener:

Keveng
11-07-14, 13:28 PM
CLIPPED Obviously shaking the whole trike isn't an option to mix it up,
You could just rock the trike back and forth to mix it up if you are that worried, i have on occasion removed all the fuel and then replaced with new but that was when i was stuck on the ground for a month or so
Keven

Andymackk
11-07-14, 13:29 PM
Ha Ha - there's load of those sayings - we would need an interpreter for most of them :-) Just as you say, by adding fuel before a flight ( rather than After a flight) would probably go a long way to remixing any existing anyway. And as Joan says - just get out more :-)

Rog
12-07-14, 01:29 AM
Ha Ha - there's load of those sayings - we would need an interpreter for most of them :-) Just as you say, by adding fuel before a flight ( rather than After a flight) would probably go a long way to remixing any existing anyway. And as Joan says - just get out more :-)

would agree that getting into the habit of adding say only 10l before going somewhere would be good practice for mixing whats in there

ajojets
12-07-14, 06:30 AM
You don't need to get too paranoid over 2-stroke fuel/oil ratios. Measuring using the marks on the side of a plastic litre oil container is quite adequate - you don't need to work to that high a level of accuracy. I fill up to the 900 ml mark from my bulk container and that gives me two lots of 400 ml between the marks. So long as you are sensible and take care to end up with the oil level on the appropriate marks you will be OK. You are not dealing with ultra-sensitive, high precision devices here - there is always residual oil sloshing around inside the engine. How do I know this? Someone I know who thought he knew better confused the little oil container for the butterfly valve lub oil on a 582 with an oil injection system (I know, don't ask...) and advised the new owner of the aircraft to top the tank up with neat mogas and fly it home, a flight of about an hour. He did so with no ill effects. The tank was subsequently filled with 50:1 and the aircraft flew safely for many more hours before being sold off to a new owner.
Not sure if I'd want to buy that aircraft from him, this for sure would cause premature bearing failure and the engine would have been overheated due to excessive friction in the cylinders.

Roger Mole
12-07-14, 11:16 AM
Not sure if I'd want to buy that aircraft from him, this for sure would cause premature bearing failure and the engine would have been overheated due to excessive friction in the cylinders.

:-) Neither would I but it goes to show that these Rotax 2-strokes are tougher than we give them credit for and don't need to be over-pampered. When I was a lad we all had 2-stroke motor bikes (Francis-Barnetts, Bantams etc) and all we did was slosh in a tank-cap full of oil when we bought a gallon of petrol and they just kept on going. 2-stroke Rotax's aren't much different really - there's always quite a bit of oil sloshing around inside which is why they're frowned upon now for ecological reasons in many quarters - the excess just gets chucked out through the exhaust. I'm not an engineer (OK, it shows you say ;-) ) but in the short term radically changing the oil ratio affects the mixture more than the lubrication I think. Reduce the oil, too rich, increase the oil, too lean.