On 7/1/2010 7:15 PM, kim Blackseth wrote: > but the header tank overflows unless i block the vent on the header > tank cap.
First, do no fly with the header cap vent blocked. Ever! There is (should be) no difference between a C and a D header cap. I suspect the problem has to do with mixed and matched components, or incorrect plumbing (really the same issues.) Someone mentioned the fuel overflow being too high in the tank. I strongly suspect the inlet and outlet on this system were reversed. The fuel must come into the tank at a higher level that the overflow. Venting problems with the wing tanks could also cause your problem as well as incorrect connections at teh wings. There are 4 different fuel systems used on the 415's. The differences are covered in the service manual. If components from two different systems are combined, care must be taken to come up with a configuration that works... -- John Cooper Skyport East www.skyportservices.net
