water in carburetor sinks
in 912 / 914 Technical Questions
12 years ago
Hi all, I am new in this forum, I have a very short experience as pilot (350 hrs)
I fly here in Eyrope an Eurostar with 912ULS, 100hp with airbox.
In winter foggy days, I usually fly in the sunny Alps between 10000 and 14000 feet, usually 2 hrs flight lenght.
I check fuel tank and filter for water before every flight (never found); I refuel with water filter, I cover half of the radiator with tape.
In the long descent I usualy pull carb heat, trying to keep CHT and oil around 70° C
In the first 100 hrs service, the mechanic here (rotax certified) find 1 spoon of water in both carb sinks: nothing in the fuel filter, nothing in the tank.
He said: “ you fly in winter, you have condensation inside the airbox that goes inside carbs...the solution is to put a temp sensor inside the aibox, and when you go below 18°C , pull carb heat no matter if you are climbing or level”
And so we did, but at 200 hrs service I still had water (1 tea spoon), I use more carb heat and at 300hrs service I still have water (1 tea spoon)
When I pull carb heat I have an evident power decrease, not nice to feel when in the mountains...
Any suggestion?
Do I have to empty carb sink more frequently?
Is the carb heat an “all or nothing” control as the manuals tells,or I can use it also gradually, just to keep my right temp in the airbox?
thanks
I fly here in Eyrope an Eurostar with 912ULS, 100hp with airbox.
In winter foggy days, I usually fly in the sunny Alps between 10000 and 14000 feet, usually 2 hrs flight lenght.
I check fuel tank and filter for water before every flight (never found); I refuel with water filter, I cover half of the radiator with tape.
In the long descent I usualy pull carb heat, trying to keep CHT and oil around 70° C
In the first 100 hrs service, the mechanic here (rotax certified) find 1 spoon of water in both carb sinks: nothing in the fuel filter, nothing in the tank.
He said: “ you fly in winter, you have condensation inside the airbox that goes inside carbs...the solution is to put a temp sensor inside the aibox, and when you go below 18°C , pull carb heat no matter if you are climbing or level”
And so we did, but at 200 hrs service I still had water (1 tea spoon), I use more carb heat and at 300hrs service I still have water (1 tea spoon)
When I pull carb heat I have an evident power decrease, not nice to feel when in the mountains...
Any suggestion?
Do I have to empty carb sink more frequently?
Is the carb heat an “all or nothing” control as the manuals tells,or I can use it also gradually, just to keep my right temp in the airbox?
thanks
