Fuel tank

[Mike406]

Had problems with fuel supply seemed like blockage from the tank
So taken tank out and can see a round tube where the fuel pickup pipe is aligned
Took drain plug out which was quite “gungie” but i can’t see how clean it all is

Any ideas welcome

Mike

[JoeF]

That's a baffle tube, which sits above the sump and drain plug. Petrol can flow into the base of it from the rest of the tank - and the two petrol pick up pipes sit inside the tube
If you have the tank out, you could check that side of things by pouring some petrol down inside the tube using the reserve/pickup unit opening, and checking that it flows out into the tank from the bottom of the tube ( with the drain plug back in ). That would imply no total blockage there.
If you have one of those extending magnetic pick up tools, then see what that picks up from the bottom of the tube, and around the outside of it.
If your drain plug is brass, check it for reddish/pink colouration before you re-use it. I didn't and it sheared off on tightening possibly due to weakening by the leaching away of the zinc content over the years.
If there is no blockage in the tank itself, the next suspect would be the reserve/ pickup unit. The pickup pipes can get blocked or develop splits - and the head of the unit can get corroded and clogged up.
One thing I found on my 405 - is that the fuel line had been squashed somewhat, by someone using a jack just forward of the left rear wheel arch. The line crosses the bottom of the chassis here. Perhaps it is the same on a 406.
While the fuel line is drained it might be worth cleaning out the fuel tap in the engine bay. The gasket for the tap is easily available, as the same type is used on Massey Ferguson tractors.

[Mike406]

Hi thank you for your thoughts

I have been able to remove the drain plug and will replace the sealing washer

is the tube in the bottom of the tank solid or perforated

how does the fuel get into the tube in the tank as the tube looks to be 3-4" tall

I have used a spray gun with a long lance with boiling water in it to blast around the tube then left it in the sun to dry out so have another look today

sorry if these comments seem a bit confused

once again thanks

Mike

[JoeF]

There are openings at the bottom of the tube, I think, so that petrol can get into it from the sump. I haven't actually seen what's there properly as I didn't have a boroscope camera when I did the 405 tank - it would have been useful to have a good look around. If you put your water feed into the top of the tube and the water makes its way into the into the rest of the tank, then it isn't blocked there. Or just put the drain plug back in, add some water to the tank via the main petrol filler pipe and check that it also rises in the tube.

[Mike406]

Hi thanks again

had a good look in the tank as best as I can

took your ideas and fed water in via the main filler, the inner tube and the drain plug all worked as you said they should

the filter on the end of the two tubes which feed the output

the reserve solenoid worked ok but he soldered filter as both split and very corroded so got some new copper gauze and made up a new filter and soldered it to the pipes

so now starting to reassemble

I'll let you know how I get on next week hopefully

Mike