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<DIV>I have noticed the same thing on two different FZ motors. They also run fine, show no sign of leaking fuel and the tank holds pressure. My guess is the silicone fuel valve seals tight against pressure, but can be lifted from it's seat by the vacuum present only when defueling. Might be a sign the silicone fuel valve is wearing, but it does not seem to effect the engine when it is running. There are only couple of ways air could get into the line. Leaking regulator gasket or a leaking or loose nipple washer are two ways, but those would also allow tank pressure to bleed out. Barring either of those, the only other place air can enter is through the needle valve opening in the carb. Try closing the needle valve and see if you still get bubbles. I'll pay more attention to it this season and see if I can come up with the definitive answer.<BR><BR><B><I>Chuck Czarnik <CCzarnik@arclp.com></I></B> wrote:
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<P class=MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Ok, for the YS Gurus out there..</SPAN></FONT></P>
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<P class=MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I have a 140L, runs good. Fuel system has no leaks. However, when I defuel, the pump sucks air bubbles in the fuel. If I pinch the fuel line at the regulator, the pump primes and no more bubbles. Regulator has a new diaphragm in it. Engine doesn’t appear to leak fuel anywhere when running. Something to worry about? What should I check? Thanks in advance! Chuck</SPAN></FONT></P>
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</PRE></FONT></TD></TR></TBODY></TABLE></BLOCKQUOTE></DIV></DIV><BR><BR>Bob Kane<br>getterflash@yahoo.com<p><hr size=1><font face=arial size=-1>Do you Yahoo!?<br>
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