Just got back from
@border
The fuel problem is still present. When I turned up, lift pump #2 was fitted. This had a piece of hard plastic nylon from the lift pump upto the fuel filter housing. It had signs of air in it, large bubbles as shown in the video uploaded earlier in the thread. I checked the unions on lift pump #2, these were slightly loose, so nipped them up. This appeared to fix the problem instantly. That was until we turned the engine off, and left it a few minutes, then started it, only to find as much air as before I nipped the unions.
At this point, I placed a piece of clear tube where the hard nylon one was, fearing the air could be brought in by the nylon having a less than perfect seal. This didn’t make any difference. I then placed a piece of clear pipe just next to the pickup pipe, this showed no signs of air. Next was to place a piece of clear tube on the inlet to the lift pump, this didn’t show any signs of air at this point.
So at this point in the diagnosis, clear plastic pipe was at 3 points, fuel pick up, lift pump inlet, and lift pump to fuel filter. Only the lift pump to fuel filter had air, so I suspected the lift pump to be faulty. Off we go to a local motor factors to purchase a new lift pump, a Bearmach branded pump, lift pump #3.
Fitted lift pump #3, same as before, only this lift pump was struggling to draw fuel from the fuel tank. It wasn’t drawing air into the fuel line, as the clear pipe at the pickup was full of fuel and no air was present. It was trying to push fuel out as you could see bits spluttering up the clear plastic to the fuel filter housing. Wondering if this was caused by an airlock inside the lift pump, we removed the clear plastic from the lift pump output and placed it into a Jerry can. This ran the engine perfectly, fuel was drawn from the tank upto and out of the lift pump spurting towards the bulkhead. Quickly moved the fuel line from the jerrycan and back onto the lift pump, started the engine again, same as before. Struggling to draw fuel from the tank.
At this point I realised the fuel line from the filter to the FIP had a join in it, so replaced that piece for clear plastic. This didn’t do anything to the fault.
The final trial was to put the fuel lift pump pickup pipe into the Jerry can to see if it could draw from that. It didn’t draw any fuel through that pipe.
The original lift pump, #1, was old and showed no signs of pumping at all, this was replaced before I arrived. Lift pump #2 & #3 both show signs of pumping when off the vehicle. If you pump the lever and cover the inlet, it sucks and appears to work as it should. Apart from replacing the lift pump again, I’m out of ideas.