01 Xj Fuel Pump Check Valve Question

[cmk4425]

I dropped the tank and removed the fuel pump. Both strainers are filthy and the inside of the tank is also dirty. Anyway I was messing around with the lovely all-in-one fuel filter/regulator/check valve and I noticed that if I squirt degreaser in the output that it freely flows out of the input. Am I wrong but shouldn't the check valve if working properly stop anything from flowing this way?

[bigjim350]

to me it seems as though the check valve would stop fluid from coming the other way, could be wrong though

[cmk4425]

Thats what I think also. Once I get a new one I am going to cut the old one open to see whats inside:thumbsup:

[LizardRunner]

the check valve is to keep pressure in the fuel line to the rail, so it would allow fluids to flow up stream but not down stream. I think it is also spring loaded so that pressure has to be present for it to work, I may be wrong on that, but most of them I've seen are.

[cmk4425]

That makes sense. I am replacing it anyway. I will let you know once I cut it open.
the check valve is to keep pressure in the fuel line to the rail, so it would allow fluids to flow up stream but not down stream. I think it is also spring loaded so that pressure has to be present for it to work, I may be wrong on that, but most of them I've seen are.