Brian,
First, thanks for your service to your country and us.
Regarding fuel pressure issues.
1. There's a fuel cutoff switch on the passenger side firewall to the right of the jug your windshield washer fluid goes in. It has a large black rubber top on it, try pushing that and see if that solves the problem.
2. The fuse box is also on the passenger side. Next to the coolant recovery tank on the fender. It's a black box, lift the lid off. The fuel pump fuse is on the left, counting down from the top it's the 6th one down from the top (should be numbered 6), check that and see if fuse is bad.
3. Fuel Relay is also on passenger side fender under the computer (black box on fender next to windshield washer fluid jug, if the manual is correct.
4. Also, if it's been sitting awhile could be the fuel filter is plugged. This is located on frame by right rear tire (small metal can with 2 fittings on it), you may want to replace it. Just pinch off the fuel lines before you remove it or you'll have gas all over the place. (Suggest you put a bucket under it to catch any runoff.
I hope this helps. Absent any of this it could be a bad fuel pump. Fuel pump is expensive, you may get a used one, suggest you go to
www.discoweb.org and contact Wil Tillery. If you do a search there you can also find out how to replace the motor in the pump with an aftermarket one that's probably less than 1/3 the cost of a new fuel pump. Removing the fuel pump isn't bad, if you remove the plate that holds the carpet down in the back door you can lift the carpet, you'll see a hatch with screws there, remove it, the fuel pump is right there. You will need new fittings as re-using the old ones will most likely cause a leak. To remove it you unplug it, then it's like a giant baby bottle, just undo the plastic ring then the pump comes right out.
I e-mailed you a PDF Manual for D1 in case this may help you.
Good luck.
If I can be of further assistance my e-mail is
jhmover@comcast.net.
Also you could try
www.lrrforums.com.
Between the 3 forums there's plenty of people who know more about Land Rovers than I do.
