2-stroke in carburettor bowls???

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Dunesand
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2-stroke in carburettor bowls???

Postby Dunesand » Wed Apr 08, 2009 4:58 pm

Hi Guys,

I need some help/information: Whenever my trike (582) stands for few weeks, I always find the bowls, especially the rear one, filled to normal float level with 2 stroke oil - very little petrol with it (evaporated perhaps). It's an autolube system and only logic I can make out is because the 2-stroke tank is higher than the carbs, oil with it's higher density will continously try to settle at the lowest point being the carb bowls in this instance. And, I suspect, as the petrol in the bowls evaporate, the floats drop and open allowing the "heavy" oil to push through.
Engine starts very easy though with full choke once I have emptied the bowls.
What could possibly be wrong?
Any advise appreciated.
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Morph
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Re: 2-stroke in carburettor bowls???

Postby Morph » Mon Apr 13, 2009 9:51 am

Interesting question. I doubt very much that the petrol has evaporated leaving the oil. Firstly the float bowl is sealed to air when not running. You can leave a can of fuel, premixed for a few months with no evaporation.

If it is pure oil then it must be seeping in from your oil tank. next time, when you stop, mark the level on the oil tank. Then check if this level drops.
Greg Perkins
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Wargames
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Re: 2-stroke in carburettor bowls???

Postby Wargames » Mon Apr 13, 2009 10:11 am

Morph wrote:If it is pure oil then it must be seeping in from your oil tank. next time, when you stop, mark the level on the oil tank. Then check if this level drops.
Do as Morph says!!

The question is really about how does the oil get to the bowls!! An autolube system feeds oil directly to the crankshaft. There isn't suppose to by any in your fuel line. Better check it out quickly to make sure your gearpump is working properly. Better get advice about this from your ap!!

Regards,
The Naked Trike
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MADDOG
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Re: 2-stroke in carburettor bowls???

Postby MADDOG » Mon Apr 13, 2009 6:20 pm

My engine does the same. I believe it is normal. Depending on where you park the prop, one rotary valve is open allowing fuel to evaporate. I do know if the oil seeps in through osmosis, but if it really bugs you then you must fly more often and not allow time fir the fuel to evaporate. :wink:
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