Jaguar Repair/1984 xj6


After draining the fuel tanks i put 5 gal. of gas back; but i'm only getting air pressure from the fuel pump. What do I have to do to get the fuel to flow?

Hi Ivory,

If the pump is trying to pump air with 5 gal in the tank then you either have the wrong tank selected or you have a failed tank switching valve in the bottom of the spare tire well.

When the left tank is selected (default tank) you should have no power on the valve. The valve is spring loaded to the left tank and when power is applied it should "Click" and close off the left tank and open the right tank.

The preliminary test is to disconnect the power wire from the valve and leave the ground connected. Then apply a powered jumper wire to the loose power wire on the valve. You should hear and even feel a "Click". You should also hear a "Click" when you remove the power. This is the spring returning the valve to the "Left tank open" position.

If you have this and still not getting any fuel from the left tank you need to pinch off BOTH large hoses from both thanks and remove the valve and bench test it for open and close operation and check the flow of fuel from both tanks.

When you get it working, let me know and I will go over the tests for the return valves and the switching process.


Jaguar Repair

All Answers

Answers by Expert:

Ask Experts


Howard M. Fitzcharles III


Jaguar from the XK 120 to XJ-6 ser. 3 1987


Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.

Associate member SAE EAA member

Import Car magazine

ASE Master Auto with L-1 certification up to 2000

©2016 All rights reserved.