Repairing Landcruiser Tank Changeover Solenoid

Tank solenoid to switch between mains and sub tanks are very basic parts containing a solenoid and a valve that it controls. These changeovers are basically the same across different makes so this may help you. They can easily be disassembled and reassembled although metal fatigue will be an issue if this occurs to many times. They are not designed as a serviceable part.

I was quoted over $400 for a new solenoid so this easy task is well worth a go first.

The process is the same for the main or return solenoid. The main being the larger of the two.

Supplies

You will need

Multi meter
12v power source (can just test in the vehicle)
multi grips
vice
hammer
Liquid electrical tape

Step 1: Remove Tank Solenoid

Diesel Landcruisers have two solenoids: 1. The main feed 2. Return line. If the main fails the symptom is no fuel when switched to main tank that contains fuel or trying to switch to a tank with fuel and the other is empty and continues to draw from empty tank. If it’s the return playing up, the tank that is selected will empty quicker than usual and the other tank will start filling up. This is because it’s drawing from one tank and returning to the other.

80 series wagon has the two solenoid mounted to a bracket that is then bolted to the vehicle between the two tanks.

Before removing the solenoid, test it by getting someone to press the sub tank button a few times. If it’s clicking you should be right to open it up. If not then it may be dead. In any case it still needs to be removed. If you can tell if it is working or not by doing this, use the mult meter to test for continuity. A solenoid is just a simple coil.

Disconnect the solenoid and hoses. Unbolt the bracket and mounting bolts of the solenoid. I bent the bracket to get access.

Step 2: Disassemble the Solenoid

Using a pair of multi grips or similar, start uncrimping the metal solenoid from the plastic valve body. Use the multi grips to bend the housing out and work your way around the entire valve. Keep going until the plastic valve cover is able to be removed. You may need to push on the bottom of the solenoid where the wires are to get the valve to pop out. Be careful doing this and also avoid using anything to pry out the valve are you may damage it and create a leak.

Step 3: Inspect

These are very basic . The solenoid allows the valve to remain in the usually open position drawing fuel from the mains. Once energised the solenoid lifts black valve, pushing against the sprint and closes off the mains and draws from the sub tank. In my case I had a chunk of crap in the plastic spacer blocking the main feed. Check the black valve and plastic spacer for wear. If anything is unserviceable, you will either need to remake it or scavenge from another part as these are not readily available to my knowledge.

Once the valve side is inspected and repaired if required, check the solenoid internals for wear. Replace the plunger seal if required.

Step 4: Reassemble

Reassemble in reverse order of disassembly. Insert plunger into solenoid. If new seal added, smear with a bit of diesel to make easier to install. Place the plastic spacer grooves down. The black valve has a small locating hole for the tip of the plunger. The spring sits on top of that. Place the plastic valve body back on. I found using the vase to gently hold the solenoid body a big help. Align the middle valve body tube with the wires of the solenoid.

Recrimp the solenoid body back onto the valve body by gently tapping the metal end with a hammer. Work around the entire valve and gently tap a little at a time. Maintain alignment and make sure valve is fully seated. Keep tapping until fully crimped back in place and valve is secure.

Check for leaks before reinstalling.

Check the electrical connections are free of corrosion and damage. If the proactive coating was damaged or has been removed, apply liquid electrical tap or similar.