---------------------------------------------------------- Rocket-List Digest Archive --- Total Messages Posted Sun 03/28/04: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:36 PM - IO-540 fuel pump ??? (Tom Gummo) ________________________________ Message 1 _____________________________________ Time: 04:36:49 PM PST US From: "Tom Gummo" "Rocket List" , "RV List" Subject: Rocket-List: IO-540 fuel pump ??? --> Rocket-List message posted by: "Tom Gummo" Fuel Pump questions????? I have an IO-540 J4A5 version engine and it has the square fuel pump: Lycoming part number - 74547 Description - Fuel Pump (RG-17980) It has two small (AN-2) fittings, one on either side of the case and I was told they were drains or overflows of some type. So, I connected them to small tubing and ran them to the bottom of the cowl where they would drain away from the exhaust. 1. Does anybody really know what they are? When the engine is running, the engine fuel pump provides 25-30 psi pressure. The electric pump puts out 35 psi. With the engine off and the fuel system pressurized with the electric fuel pump, fuel comes out of one of them. 2. Is this normal? I have been chasing a oil leak, one of my oil cooler lines, less than two years old, decided to give up and was replaced. So, I have been checking all the little drops of oil on the floor after each flight to make sure that I fixed the problem. Yesterday, I found two drops of oil and it appears to have come from one of the engine mounted fuel pump drains. 3. Is this normal? 4. Is there is diaphragm with oil on one side and gas on the other in this type of pump? I just want to make sure that the pump isn't showing signs of failure. Thanks, Tom Gummo Apple Valley, CA Harmon Rocket-II do not archive http://mysite.verizon.net/t.gummo/index.html