Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Fuel tank not filling

Anyone ever had problems filling fuel? Seems like crossover for the saddle is blocked or something. Can only fill/use half the fuel volume. Any advice welcome!

How have you determined that, if by the fuel gauge it is notoriously unreliable. You should be able to be able to get 250 to 300 miles from a tank.

Yes, I used to get that, but now I can only get about 4 gallons in and 150 miles I have always laughed at the gauge accuracy! 🤣

If you tap each tank with something metallic (small hammer) you should get a full vs hollow sound from alternate tanks to show which side is at fault ?

The lower crossover pipe is quite large, so a blockage would be highly unlikely unless someone has been stuffing socks into your fuel tank. There is also a high mounted air transfer hose to allow air movement between the tanks, and if this is kinked or blocked fuel won't flow between tanks.

Also, M3Ws are sensitive to the method of fueling. If you try to fill at too high of a rate the pump will shut off before the tanks are anywhere close to full.

Ideally you should be fueling from the left side of the vehicle (gives a more favorable angle for the pump nozzle) and you should fill either at a slow rate (preferred), OR, when the pump clicks off, wait a minute or so (to allow the transfer tube to do it's work) then pump again.

And as noted above, you cannot rely on your fuel gauge, so are you sure your tanks are near empty when you are trying to fill them? These machines really need another type of sending unit.

All good advice however don't overfill the tank. Good practice is to fill the tank slowly and stop when the pump auto cutoff triggers 3 times. If you fill to the brim, particularly in hot weather, you run the risk that the engine may not start, run rough or cut our. It this happens and you can get it running then drive for 5-10 miles to clear the problem.

The fuel gauge reading will vary over time. Mine can be on zero in anything from 40 -120 miles!!! So it's best to totally ignore the fuel gauge and just set the trip meter when you fill up and fill again after 200 miles or so.

Would guess at the left hand tank breather being blocked - its just a pipe that runs from top of left hand tank to fuel filler neck.
Just have to take out rear boot tray.
If its not that then fuel pump out and look inside tank as you can see the crossover 'inlet' at the base of the tank, perhaps something has blocked the hole off?

Did you actually run out of fuel? I'm a new M3W owner and I did about 600 miles last weekend. I fueled up every 150 miles or so as the guess-o-meter read 0% after that. When I went to fuel it, I also got about that amount in every time. However, I did not run out of fuel and when I tap the tanks they sound the same.

My M3W has a short fuel sender in the tank which reads 0% when the tank is at about 40% The accuracy of the fuel sender can however deteriorate over time due to sediments on the wires inside the sender. This causes the sender to give faulty readings more and more the older it gets. Maybe it's just the sender that's at fault and you could still do more miles than you think?

If you're handy with a spanner and a screwdriver I would do the following:
- Fuel up the car completely. If the dash reads 100% you are sure that the right tank is completely full as that tank contains the sender unit.
- Shortest route home, and take out the bootliner to expose the tanks and their connections
- Undo the fuel hose from the top of the left fuel tank. It's the narrowest hose and it serves as an overflow/breather for the left tank. No fuel should come out, but do be careful and keep some rags at hand. You never know with a Morgan
- Stick a rolled up piece of paper (don't let go!) or something else into the hole in the tank, see if it gets wet. If it does, you know both tanks are full.