Author Topic: Broken Duckbill  (Read 1316 times)

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Guaire

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on: June 15, 2013, 04:20:20 pm
Opened the canister and found a broken duckbill. The gasket of the can was a wreck too. I assume this means the crankcase was not able to create the less than atmosphere pressure to reduce resistance of the piston. This is my first experience with this type of motor. Will a good duckbill help the crankcase and stop losing so much oil?
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ace.cafe

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Reply #1 on: June 15, 2013, 04:32:28 pm
Yes, a good working duckbill is a good help for reducing crankcase pressure, and helping the rings to seal better, and helping the engine to run cooler and more efficiently.
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Guaire

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Reply #2 on: June 15, 2013, 04:51:00 pm
Yahoo! It was good to find this problem. Now I can improve the oil use, mileage and more.
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D the D

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Reply #3 on: June 16, 2013, 12:52:17 am
A layer or two of plastic electrical tape will serve just as well or better then the original gasket.
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Guaire

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Reply #4 on: June 16, 2013, 02:59:47 am
  In desperation I got an automotive PCV check valve. I set up clear vinyl tubing from the crankcase port, going up and back. Used an adapter to 1/2" tubing, attached the check valve. The valve is pointing down to help it keep its seal. Out the top of the valve, I extended a hose in back of the side panel,  around and down to the swing arm, held down with zip ties. The nasty oil can get out there.  This is the first time I've had a working seal = duckbill.
More at the 32mm topic.
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Guaire

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Reply #5 on: June 18, 2013, 08:33:51 pm
I got some pix of my home made duckbill tubing with an automotive PCV (check valve) in line. The tube is not releasing used engine oil on the chain.
Since there is negative pressure in the crankcase, the tube is not constantly sloshing engine oil, like it used to. With the negative pressure, oil has a tendency to stay in the motor and not to go everywhere else, like it used to.

The elements of an engine =
Fuel, Spark, Compression, Duckbill.
The engine will run with three, but it only does it right with all four.
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