New Fuel Valve question

How to keep the Cessna 170 flying and airworthy.

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piclr60
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Joined: Tue Oct 23, 2012 10:03 pm

New Fuel Valve question

Post by piclr60 »

I have investigated the forums on all the info on the fuel valve. I understand how it works and the pit falls on the cam riding up or down to allow the balls to fall in the valve shutting fuel off. I may have missed something but what would cause the fuel valve to not shut off fuel at all? Fuel still flows in the both off positions. I thought i read somewhere on the forum the cause of that but can not come up with where I read that. I also scanned the fuel valve article George wrote in the 2011 1st quarter. Any help please?

Thanks

Brad
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johneeb
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Re: New Fuel Valve question

Post by johneeb »

Brad, have you taken the valve apart and determined if the balls are missing?
John E. Barrett
aka. Johneb

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GAHorn
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Re: New Fuel Valve question

Post by GAHorn »

If the valve is assembled incorrectly ( as the IPC illustrates with the O-ring improperly placed) the fuel will never shut off completely.
The article I wrote which used the later Service Manual illustration is the correct method of assembly.
It's good you have caught it and can repair it before it causes a problem.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Re: New Fuel Valve question

Post by Bruce Fenstermacher »

If the o-ring the ball seats against have rotted and broken the valve will not shut off in that direction.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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piclr60
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Re: New Fuel Valve question

Post by piclr60 »

Laughing out loud as I read the last post!

Pulled the valve out yesterday! Wow. Hope I don't have to do that again. I found out that one of my o-rings was out of the retainer on one side which was why I could not shut the fuel completely. Also I had no bushing in my valve at all. I could push the cam down but it was a fair amount of force in order to do so. Rebuilt the valve with the McFarlane rebuild kit and put the two washers George recommended instead of the bushing. When I put it back in I used nutplates to save me pain!! Seems to be holding fuel when I left. Will see if I have any fuel left in the airplane in the morning.

Thanks for all the help from everyone!

Brad
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