Carb to inj - what needs to happen with the tank?

[HARDCORE]

Hi y'all!

I have a car with a leaky tank, which is an cos it's got just over 3k on it (tho in about 10 years..) and 'looks' mint I took it off today and the bottom seam appears to have blown

I'm not gonna weld it up myself (can't be dealing with the stress of cleaning it out, only to blow myself up anyway) so my first question is: can anyone recommend someone (pref down south as I can't post it obv..) who would be able to offer this service?

My reasoning for not simply sourcing a replacement is hopefully explained by my second question:

I plan to (at some point) change the engine in this car - it's currently running carbs but the new engine will be more 'modern'. Please can someone explain to an old fashioned idiot what changes will need to be made to the tank to make this possible? Is it simply somewhere to run in a return line from the engine? (presumably at the top of the tank?) Can it go into the filler neck? That would be much easier

I'm sure you see already, as the tank is out I might as well get this sorted now

Many thanks in advance for your helps!

[carmad]

they need a return pipe

I used a t peice and an exhisting breather pipe on my manta turbo

some times it will pressureize the tank tho depending on the volume and pressure off the electric pump

so i drilled a tiny hole in the filler neck just inside the filler cap to stop this



but if your getting a new tank made just get a propper connection welded in to it

[ChrisT]

you'll probably need a swirl pot as well - either in the tank or externally, so the pump doesn't suck in any air

[Steve]

I would prob go with a new carb petrol tank, get a external swirl pot as and when you do the engine swap along with a low pressure pump to draw the fuel up from the tank to the swirl pot then a high pressure pump drawing from the swirl pot to the engine. Return from the engine then goes back to the tank, if there is space within the tank sender assembly id just drill a hole and somehow put a pipe in there........its difficult to explain that last part but it does work

A return into the filler neck can cause issues with leaks sometimes, especially if its upwind of any rubber joins from filler neck to tank......but should work if the above isnt an issue

Steve

[diff]

when I fitted the sr20det in the cortina I put the return into the filler neck, I soldered a 8mm copper line in angled towards the tank, with a 1 litre swirl pot fed by a facet silver pump , whch then gravity feeds an injection pump.
When I done the zetec in the viva the return went into the top of the tank, due to the shape of the tank (vertical inside a rear quarter) I did not bother with a swirl pot and it has been ok for quite a few years now.

[popuptoaster]

depends on the shape of the tank as to being able to get away without a swirl pot, pump needs a constant feed because its lubricated by the fuel and because the injection system needs to remain pressurised, theres no float bowl full of fuel like on a carb.

You can either run a seperate swirl pot fed from the tank, usually filled by a low pressure pump although in some cases you can get away with a gravity feed.

don't fit it in the boot though unless you have a fireproof rear bulkhead.



you could also fit some baffles or a sump in the tank and run an internal pump which cuts down on exterior plumbing but is more awkward to set up, that how i'm doing my Transit van, i've modified the Scorpios sender unit and pump assembly to suit the Transit tank and will get the mounting welded into the top of the tank and a sump welded into the bottom.

If theres an injection tank available for your car though just buy one of them.

[bortaf]

might help if we knew what vehical it was ?
some golfs have a nice compact external swirlpot/lft and main pump all in one unit under the boot floor.
You don't have to run a swirl pot, i know quite a few peeps who just braised in a larger bor pickup pipe into the sender plate and added a return if one wasn't already fitted but that requires the tank to be kept at 3/4 full all the time or you get fuel starvation on corrners but again it depends on what vehical it's on and the tank design, Mk1/2 escorts can get away without a swirlpot at all

[HARDCORE]

Sorry chaps, it's my Mk2 Escort in question - dunno why I didn't mention that

I don't think they were ever made with EFI and can't find anyone selling new tanks for them (excepting fancy alloy / rally jobbies)..

Thanks for your help

[RetroWarwicK]

In the current edition of PPC, one of the articles mentions a Mann injection fuel filter (and part number) that has a return pipe built in, so you can get way with not using a swirl pot/return pipe to tank.

[popuptoaster]

You wont need a swirl pot in a mk2 escort, so you just need a to get a bigger outlet welded in for the high pressure pump, use the old outlet for your return line, its been done that way loads with escorts and works fine.

[bortaf]

escort to efi
www.dominicbolton.freeuk.com/injection.html