Replacing fuel pump on Ford chassisForum staffer Karl had a suspected failed fuel pump on his Bounder with a Ford chassis. The fuel pump on this chassis is located inside the fuel tank. Forum member Jerry Groah offered the following procedure for removing and replacing the auxiliary pump. Forum member Jim Johnson provided the procedure for dropping the fuel tank to remove the in-tank pump.
Procedure for installing an auxiliary fuel pump on an F-53 Chassis1. Remove the fuel filter. The filter is located between the chassis frame approximately below the drivers seat. This all has to be done from underneath the coach. The fuel lines connected to the filter has quick disconnects that require a special tool to disengage the locks. Tool can be purchased for less than $10.00. AC line disconnect tools can be used.
2. The filter is in a bracket that must be pried apart slightly to release the filter. Leave this bracket in place as it will be used to support the pump. The pump kit you get from Ford has a bracket also which you will not need. The kit has a piece of foam which is used to insulate the pump and prevent noise. The foam is wrapped around the pump and pump is installed in the above mention bracket.****
3. Install the fuel lines on the pump. Make sure you have the pump oriented correctly. The electrical connections will point toward the front of the coach. The fuel lines disconnected above will snap right on to the lines on the pump. There is one caveat here. You will not be able to disconnect the lines from the pump with the tool mentioned above; there is not enough space between the pump body and the quick disconnect to install the tool.*
4. Proceed to wire pump to 12 volt source. Pay attention to polarity of pump. I used a direct 25 amp source with ground directly back to the coach batteries. I installed a 25 amp switch on the dash and labeled it. The 12 volt source came directly from the battery with an inline fuse. You must turn pump on prior to starting the engine and turn it off upon stopping the engine.
5. Some folks could wire the pump using the ignition switch to turn the pump on and off. But this entails using a relay and more complicated wiring.
* When switching back to the fuel filter, I had to cut the fuel lines and take them off the vehicle. Then you can remove the locking fingers. Obtain new ones before reinstalling the lines. The lines were cut close to the body of the pump. This scraps the pump.
** This installation lasted about two/ three years on my coach. I eventually had to change out the main pump in the tank.
*** This installation also leaves you with out a filter in the system. You could by using the discarded bracket and having a special jumper line fabricated to use between the pump and filter, install the auxiliary pump. The pump would be installed down stream of the filter. The outlet line would also have to be shortened. In this case the filter would be left in place.
**** The Ford part number for the kit is, F6PZ9H307DB. I bought mine from Rockauto on the net. About half of Ford's price.