Hi,
I am in the process of plumbing my first Gasoline engine and fuel tank setup.

I am using a 3 line system.

It just does not seem correct/proper to terminate the vent line by just having a piece of Tygon hanging out the bottom of the cowl.

Should there be a filter in the vent line to prevent crud from blowing back up into the tank?

Is there a fitting available to terminate the vent line at the bottom of the aircraft?

Just want to make sure my set-up is bullet proof and avoid any problems.

Thanks,
Ken -MI

your vent line should be long enough to wrap around the top of your tank then out of the cowl. I have a DL50 that the vent line comes from the tank and makes three loops that I tied to the engine box then down to the cowl. Any dust or trash has a long way to go before it ever makes it to the tank.

See Don's Hobby Shop for vent line filters.

http://www.donshobbyshop.com/

I know you asking more about whether or not to have a filter, but what I do for the vent line exit/termination is use the same thing as for the filler - http://www.slimlineproducts.com/onli.../f1_fueler.htm. I run the vent out through the bottom of the plane just ahead of the fuel tank as opposed to running it back up into the cowl.

Dan

As long as the vent line has a U-loop in it, any exit position is fine. Some route it towards the fuselage end.
A filter in the vent line is not needed. Any dust that makes it up that line without sticking to the wet line wall would be a miracle. The line is flushed each time the tank is filled to overflow.

Thanks to all for the valuable insight on vent lines! All suggestions and ideas are 'right on' and much appreciated!

Ken - MI

Listen to pe reivers......He knows his gassers and will give you the correct procedure..