fuel tank drain

[Guest]

Hi everybody

I was going to drain the fuel tank yesterday to hopefully get rid of some rust which is occasionally blocking the fuel line to the pump. I read most of the articles here about engine cut outs, fuel tank, carbs etc. and just want to say that after experiencing engine cut outs especially going up steep hills I have replaced the pump twice now, all filters and diaphragms in the carbs as well as installing an additional filter in front of the pump. Have checked the spark plugs and ignition as well. But still experiencing cut outs.
I know I need to treat the tank for rust but was hoping to get some nice weather driving in before doing this. I was expecting to see a drain plug under the boot as shown in the Rimmer catalogue. But nothing there only a massive plug more suitable for ship's diesel near the rear axle. Or is this the one?
What is actiually the plug next to the fuel line for?

cheers Hans

[stagmuffin]

some early mk1 stags were fitted with a drain plug which protruded through a hole in the boot floor,depending on the position incline of the car it is possible to drain from here but caution should be advised here .most of the fuel tanks are 40 yrs old and older in cases turning a plug to undo which has probably never been undone in its life may twist and tear the sheet metal tank.my advice would be to simply remove the tank completely you will need to do this to clean effectively any way .if you have depleted the fuel naturally then you only require to tip the remainder into a storage suitable vessel with a cap .two people would be advised to do this to ensure no spillage and obvious precautions would be required as dealing with highly flammable liquid.

[Stagdad]

Can you not pump the fuel out by adding a long fuel hose off the under bonnet filter.

[Ian P]

I found it easier to remove the tank, if youve got alot of fuel in remove the tank unit and do like Steve says syphon with a hose through the unit hole, once out I had to blast the inside with steam cleaner on the hottest & highest pressure setting to get rid of the loose crap that had built up over the years, I then through a bit of brake cleaner in to swill the residue away then the heat from the cleaner had made the tank very hot I then left it in the sun for an hour (hard this time of year) the amout of crap inside was unbelievable, I just keep it filled up and has been ok

[StagnJag]

some early mk1 stags were fitted with a drain plug which protruded through a hole in the boot floor,depending on the position incline of the car it is possible to drain from here but caution should be advised here .most of the fuel tanks are 40 yrs old and older in cases turning a plug to undo which has probably never been undone in its life may twist and tear the sheet metal tank.my advice would be to simply remove the tank completely you will need to do this to clean effectively any way .if you have depleted the fuel naturally then you only require to tip the remainder into a storage suitable vessel with a cap .two people would be advised to do this to ensure no spillage and obvious precautions would be required as dealing with highly flammable liquid.

The repro tank I bought a couple of years ago also had a drain plug in the bottom, so presumably they all have? Steve's comment about damaging the sheet steel still applies though, I was given similar advise when I was messing with my domestic hot water tank fittings. My tank is missing the internal baffle as well that was present on the tank I took out. I can only assume that it wasn't in the early tanks either and the repro ones were based on that.

Rgds

Dave

[wilf]

I recommend fitting an additional fuel filter in the suction line before the fuel pump. Or at least I recommend it now I copied someone else's suggestion, lol.

That way, any debris particles that do remain or collect in the tank can't hurt anything.

[KOY 23]

Not always a good idea, as many pumps cannot tolerate the extra resistance of a filter in the suction side, leading to fuel starvation as well as engine and pump damage. A coarse strainer should be fitted on the input to pump and a filter on the output.

[MandM]

Not always a good idea, as many pumps cannot tolerate the extra resistance of a filter in the suction side, leading to fuel starvation as well as engine and pump damage. A coarse strainer should be fitted on the input to pump and a filter on the output.

HI John , hope you are ok, not had that problem after fitting my extra filter before the pump (4yrs ago) but will bear that in mind if I get a problem, I change this filter yearly
P1040178.jpg

The yellow team

[Jeff]

How many filters do you need?

[MandM]

How many filters do you need?

2

[Jeff]

2

Sorry for the question mark as it was a rhetorical question.

[Guest]

Thanks everybody for your comments

I have taken the tank out now.

Yes there is a drain plug. It is the 24 bolt underneath and the tank doesn't come out until you have taken the bolt out. Mission accomplished.

However contrary as experienced by others and myself there was hardly any rust in the tank. I have treated it anyway. But where did the rust in the fuel filter come from and why is the engine cutting out when going up steep hills?
I have to wait 5 minutes switch the ignition on and hear the pump ticking away and can start again.

As said earlier, I have already installed new filters plus 1 in front of the pump, new diaphragms in the carbs, plugs looking good, electronic ignition all fine.

[Lingen]

Hans.
I have come to this problem rather late, so I hope I am not just repeating previous advice. Perhaps the fine rust in your filter has come from the places where you buy your fuel. This is not unheard of. Have you checked to see that the breather hose from the tank to the underside of the car is not blocked, and have you tried temporarily bypassing the inertia switch to the pump? If yes to all three, I will shut up!
Mike.

[MandM]

This is what came out of the filter fitted before my pump in June when I changed it.

WP_20160608_10_21_57_Pro.jpg as has been said above may come from the petrol station tanks.

[Guest]

thanks again everybody for your comments.

Just to continue the story ...

While I was waiting for the tank to dry out after the treatment I had a look at the fuel feed pipe. It was well worn round but I managed to open it up. I was astonished to see that there was a long hollow metal rod attached to it as to my knowledge this is not shown in any manual. But of course it is there to suck the petrol from the bottom of the tank by the pump.
For this the rod has a small hole at the side and here I found hopefully the culprit for occasionally blocking my fuel supply. The hole was half blocked by sort of some waxed paper..

Now removed I am waiting for some better weather to transfer the tank back to the car and see if it has doen the trick finally.