The Rover-Landers of BC

can someone that has a 2.5 n/a give me a hand with the fuel line route . i ordered all the lines and a check valve for the filter housing , and the 2.5 filter assy . there is 2 inlet and outlets on the filter housing and a spot on top for a banjo fitting . i cannot seem to find anything online where the lines should go or which line the check valve goes in etc , would really appreciate it , getting to the point where iam ready to start running fuel lines , thanks . troy

The fuel is drawn from the fuel tank through a sedimentor filter, by the lift pump. The lift pump delivers the fuel to the fuel filter, at # 2, inlet. The fuel then goes from fuel filter at # 1 outlet, to the distributor pump, (injector pump). Oversupply from the distributor pump goes back through the check valve at # 3 inlet, on the fuel filter. # 4 on the fuel filter is blocked off. The banjo fitting goes to the top center of the fuel filter. This actually becomes a "T", where the return line from the injectors carries on back to the fuel tank. This would be the highest point in the system and a good place to crack open to help remove air.
The sedimentor filter is very close to the fuel tank and as by it's name implies, allows water/ dirt to settle out of the fuel before it is spread through the whole fuel system by the lift pump.
LR uses rigid nylon line for the fuel system. I know this will start an argument but owners have used nylon air brake line as a replacement and though it will work, is NOT recommended. Caterpillar will void an engine warranty if air brake line is found anywhere in the fuel system. Usually nylon fuel line is marked as such along it's length and has a thicker wall than air brake line. Also on the inside of some air brake lines, is a fine powder coating, which can damage injectors.
A member of the Alberta Land Rover Enthusiasts club was having trouble starting his engine because the check valve was not working properly. So the check valve is important.

I emailed defenders North he recommended that both the return from the pump and the return from the injectors go to tank not the filter as this can cause air entrapment in the system and cause the motor.to run crappy . So how important is the check valve on the return line then ? I bought the lines and check valve from Jeremy but since have talked to other people who where totally unaware a check valve existed , ( they had there lines running back to tank ) . So your saying the small line that goes to the top of the filter is teed and returns to tank ? Some picks I've seen on the internet has the top of filter plugged or the line just hooks to a banjo fitting and just stops there. Never thought plumbing a filter could be so complicated lol

I guess the question is what is the purpose of the check valve ? Will it be needed if i plumb both return lines back to tank and block the top fitting and the two side fittings on the filter housing.

I would hazard a guess that if you are returning both pump and injectors straight back to the tank, then the check valve is not needed. With returns directly back to the tank, then you would only be using # 2 for supply from lift pump into filter, and after filtering, # 1 to supply fuel to the injector pump. You should be able to do as you say and blank off # 3 as it is not taking flow from the injector pump. The check valve is likely there to prevent the fuel in the filter, (under lift pump pressure), going backwards into the injector pump. I would leave the banjo fitting but capped off, so you can still crack it to bleed any air after changing filters. I would expect the return line will be the same size as the tank suction so there is no flow restriction.