My 91 XJ won't start after fixing its cranking problem yesterday. I noticed a rotted hose connecting the charcoal canister to the metal line that goes back to the fuel tank. I'm noticing it won't hold fuel pressure (gas only comes out of the Schrader valve when the pump is on prior to cranking). I've read here today that hard-starting issues related to low fuel pressure can be related to check-valves not working. The pump can be working harder when this happens so it may shorten its life.
I'd like to know about the impact of a rotted line also. Rotted is not the best description of my line from the charcoal canister, however. Mine is not dry but somewhat wet and disolving: rubber rubs off on your hands and there are some cracks that may or may not go all the way through. I may have caused it to begin leaking as I moved it while inspecting the engine during my work on it yesterday.
I haven't visited the parts store about this yet but based on past experience I think they will only have fuel lines and vacuum lines that have the same inner diameter on both ends. For this connection the metal line to the tank is about 3/16" but the connection to the cannister is about 3/8" (maybe 5/16"). It seems they shouldn't have to be stretched so much (although there's a clamp on the smaller fitting and no clamp on the canister). I have silicone vacuum hose on hand but I don't think it's supposed to be used where contact with fuel is expected (at least a quick search didn't turn up the answer on that).
Good luck to us both.
