Tank blocked or fuel pump?

[G_B_H]

Hi, got a dead ‘71 dormobile! Cranking fine but being starved of fuel. Have checked everything ignition wise. I’m now at fuel pump in/out. Pretty much nothing coming out of pump. Any idea how much fuel should be coming from tank line? I’ve had it blocked in tank before and that was flushed clean 1 year ago and small extension hose put in so sits above tank bottom. It’s the original tank and I’ve got no idea how much fuel should be seen when disconnected from fuel pump.

Thanks.

 

[ozziedog]

If you think it’s a blockage, then start at the beginning and loosen the pipe at the tank but with something to catch it and quickly pop the pipe back on. You’ll soon see if it is or isn’t blocked there. Or,,, if you take the pipe off from the fuel pump, can you blow back through to the tank? If you can, use a straw that fits or you’ll be spitting petrol fumes for the next week.

Ozziedog,,,,,,,,makes your cornflakes taste funny

 

[ozziedog]

If you can blow through, just think while doing it, did it blow through nicely or did you have to blow a small blockage through. One of the things that used to happen years ago but not so much recently was floaters. Stuff that might float about in your tank for years and just block occasionally. Years back , people would use rags to block the fuel pipe if they lost their fuel cap, dangerous and firey springs to mind but that was common with cars worth a hundred and fifty quid at most back in the day. Another thing was rubber fuel caps of various sizes and they’ve been known to disintegrate and fall in. I’ve heard of crisp packet’s that float then they don’t then they block. Sounds like you’ve had issues before too. Before you disturb anything, you could pop a cheapso endoscope down through the filler cap and actually see if anything is blocking it. The cheapso ones are less than twenty quid for an android device and they have a light on there as well.

Ozziedog,,,,,,,,,,, Floaters !!.

 

[ozziedog]

Confirm your theory by dropping a capful of petrol down the throat of the carb and should start. If it’s a mechanical pump, you can feel the pressure if you remove it and operate it with your fingers. Try that then you’ll know what it should feel like when you replace it and turn it over , put your fingers on it before the pipes go back on. Rod?

Ozziedog,,,,,,,,,,,is it a mechanical one praps ?

 

[G_B_H]

If you think it’s a blockage, then start at the beginning and loosen the pipe at the tank but with something to catch it and quickly pop the pipe back on. You’ll soon see if it is or isn’t blocked there. Or,,, if you take the pipe off from the fuel pump, can you blow back through to the tank? If you can, use a straw that fits or you’ll be spitting petrol fumes for the next week.

Ozziedog,,,,,,,,makes your cornflakes taste funny

Yes, I’m going to try and blow back. Got a solenoid valve in way on line for fire extinguisher but will make sure it’s open.

 

[G_B_H]

Confirm your theory by dropping a capful of petrol down the throat of the carb and should start. If it’s a mechanical pump, you can feel the pressure if you remove it and operate it with your fingers. Try that then you’ll know what it should feel like when you replace it and turn it over , put your fingers on it before the pipes go back on. Rod?

Ozziedog,,,,,,,,,,,is it a mechanical one praps ?

Yes, mechanical. Will look at then when happy with fuel supply to it

 

[G_B_H]

If you can blow through, just think while doing it, did it blow through nicely or did you have to blow a small blockage through. One of the things that used to happen years ago but not so much recently was floaters. Stuff that might float about in your tank for years and just block occasionally. Years back , people would use rags to block the fuel pipe if they lost their fuel cap, dangerous and firey springs to mind but that was common with cars worth a hundred and fifty quid at most back in the day. Another thing was rubber fuel caps of various sizes and they’ve been known to disintegrate and fall in. I’ve heard of crisp packet’s that float then they don’t then they block. Sounds like you’ve had issues before too. Before you disturb anything, you could pop a cheapso endoscope down through the filler cap and actually see if anything is blocking it. The cheapso ones are less than twenty quid for an android device and they have a light on there as well.

Ozziedog,,,,,,,,,,, Floaters !!.

Pretty sure no floaters, was cleaned out as best as possible a year back. I suppose some more crud could have appeared or some remained. Is it safe to put water proof boroscope into a tank of petrol? I’ve got a siphon pump so going to empty it as much as possible if I need to before emptying from outlet and flushing through. Also, pump might pull some crud out if present.

Also found dodgy fuel hose at pump out so the breakdown is a blessing in disguise!

Thanks.

 

[ozziedog]

These horoscopes <<< see what I did there Boroscope are supposedly waterproof and I’d say petroleum proof to a degree but I wouldn't want to leave it in there longer than necessary. Trouble with floaters is they can also just stick to the side or the bottom or wherever depending on how much fuel is in there. The worstest one ever was a crisp bag that would go on and off again almost on a weekly basis and sometimes not for months. This could be one of those tricky ones. After what you’ve said now, I’m wondering if your fuel pipes have collapsed a bit internally.

Ozziedog,,,,,,,, glad you found something that almost makes this worthwhile

 

[G_B_H]

Sorted and running. When checking fuel line I found the the fuse for fuel cut off solenoid on engine bay extinguisher had failed - don’t think it blown but broke due to vibration.