I have been reading the posts on the 4PT fuel systems and thought I would put in my two cents worth. I have 60 hours now and so far all systems are functioning well. I have a Frank Fry conversion that is similar in some respects to the factory belly tank, but it only extends back to the main spar and carries about 45 gallons. The fuel feeds into the right wing under the main spar via a Facet pump and a check valve. Wings feed to the firewall via a regular selector, then to a 30 psi electric fuel pump, a 10 micron fuel filter, a 3 1/2 quart stainless steel header tank/ air fuel separator, then to the engine. The header tank is similar to what John Cook has in his plane. It is a 16" x 4" cylinder. Fuel enters the top, exits the bottom. Any air that enters the system exits the top through a .050" orifice that returns to the right wing with a check valve. At the top of the tank is a fuel sensor that is connected to the annunciator panel. I mounted the tank to the motor mount as there was no room left on the firewall.

 

In regards to crashing on the belly tank, I am familiar with a gear up landing. The belly tank and the wing had leaks,  but very small, and there was no fire. This is not an endorsement of belly tanks, only that they are commonly used and a fire could start from any source. Frankly, I was quite surprised at the structural strength of the bottom of the plane.

 

Gary Garratt

408 888 1500

4PT,  N725HP

San Martin, CA 95046