Hey all, my xj has to crank a while to start (about a 10 count) and I've been putting this off long enough to kill a starter. All the pressure tests, etc, point to this. I just haven't done it. The fuel pump is fine and I won't replace it until there is a bigger problem. I just need to know the best place on the line for the check valve.
Thanks

 

Between the pump and the filter is where I'd put it. It doesn't matter where in the circuit it goes, so make it easy on yourself...

 

Thanks Jim, I was thinking on the other side of the filter, but I see your point.

 

My 90 XJ had a long crank problem that was cured by a set of 4 hole fuel injectors. Turns out one of my original factory injectors was leaking. If I primed the fuel rail it started in 4 cranks instead of 8-10. I thought initially that it was a bad check valve as well. Can't remember which injectors I used. A friend upgraded his injectors in a small block Corvette and gave them to me.
74Plb