Ford F53 Fuel Pump Problems

[Alfa38User]

The reasoning is, of course, should the gas line be damaged/severed in an accident, fuel (Gasoline) would be cut off until the problem is resolved and thus prevent a fire fuelled by gasoline....

But your suggestion is valid, of course, because these switches have been known to cut off the fuel at inopportune times. Don't know what actually causes the activation of said cutoff though, other than a severe bump. This particular 'feature' may have evolved from the old Pinto problems of many eons ago.

 

[dragvw2180]

I was a Ford tech and now am retired . The cutoff switch ( another term was rollover switch and look near the steering wheel side of cab )  is only supposed to go to an open circuit on a frontal or rearward impact only. Cutting a fuel line will NOT cause it to shut the fuel system down . The 4 wires at the fuel pump have 2 large and 2 small wires. The 2 small wires are for your fuel guage sending unit and the 2 large are for the fuel pump. You were correct , the pink wire is the " HOT " wire and should be battery voltage. The other large wire is a ground. To eliminate the ground as a cause for the voltage to be low I would check from the pink wire to the chassis with a voltmeter and see if the voltage reading changes before you start tracing wires. If it does NOT change then I would be following the harness back toward the front and checking every connector that has the same large pink wire in it. On older ( mostly class C ) units there may be 2 fuel pumps , one in the tank and another on the frame. Intank unit is a low pressure delivery pump and the one on the frame is a high pressure unit. If you need any help you are welcome to email me directly , [email protected]  ( I drag race VW Beetles ) Mike McCarthy
Just in case anyone is interested, I am driving the red car,        http://www.youtube.com/watch?v=FJZrEFElU24

 

[Jim Godward]

So who won??

 

[dragvw2180]

  The race promoter,LOL  I went three rounds then lost.  That pass was a time trial , Watch closely when I leave the line , when I shifted into second gear the front end went higher . I was ahead until I hit third gear then the back tires broke loose and it got sideways, watch it closely and you will see the smoke.  Mike McCarthy

 

[Jim Godward]

that is why I asked.  I wasn't sure what happened but figured something.  I used to watch drags at the old raceway in Long Beach CA.

 

[oneclasact]

I have replaced my fuel pump in my 1996 Winnebago Adv 37RW, twice, once with OEM which only lasted about a year, then just the pump itself, very easy to do, changing the pump on the mounting, not the actual in tank change. that part is a pain in the anatomy, I now am having a problem again and thought it was the pump but come to find out it is low voltage to the pump, only 7.7 V to the pump and 6.6 to the float, checked voltage to chasse ground and harness ground, same readings. Pump works because I put 12 V to it and I could hear it run. Cant find a schematic for the fuel pump system. all those at Winne Ind. don't show the fuel pump power. Any ideas would be helpful. May be running a whole new line, just don't want to bypass any of the safety features in the system.  ( its on a FORD chasee with 460 only 35k miles on it.)Thanks ED

 

[ACE28]

I'm having very similar issues, wondering about a key switch, and trying to figure out where the primary power comes from to the fuel pump relay.