schrator valve??

[wood350]

after my truck sits a few hours it loses prime to the pump i just replaced the ip thinking maybe it was hard starting because of that it had 170 000 miles so i figured either way it would need to be replaced sooner or later. i was doing some searching and i read that i might be leaking air through my schrator valve if this is true can someone please let me know of the where abouts of it i heard a new tire cap with a rubber gasket could fix the problem so that maked me think it is that little cap on the driver side of my fuel filter assembly top side any help is greatly appreciated everyone here on oilburners has been a great help over the last year i have own my new to me diesel BTW it a 1994 7.3 with factory turbo thanks again

 

[tonkadoctor]

I don't know if the schader valve is the same as the ones used on tires but consider replacing the injector return lines and caps. If they are painted grey they are probably the originals and the O-rings deteriorate.

Made a big difference in how my truck started

 

[wood350]

i had all thge return lines replaced when i did the ip but i did notice a rubber hose one the steel lines coming from what i think is the fuel pump to the fuel filter i will be getting that tomorrow its only about a 4 inch piece on the passenger side of the truck below the fuel filter

 

[Mr_Roboto]

The valve is supposed to have a cap on it, they get taken off and lost. A tire valve cap fits fine, the better ones have a little rubber gasket inside, the plain ones are just made to keep dirt out not seal.

Schrader valves are made to hold pressure, they aren't very resistant to air flow in the opposite direction. The cap definitely needs to be on there.

If you go get a set of the fancy metal valve caps they should have the rubber gasket in them.