running out of fuel? *updated
Turbo Mini Forums

bit of an update on this one thats still baffling me.

We swapped the pump last night for a brand new one, checked the idle fuel pressure @ 3.5psi and still it was the same. It got even worse today on the run down the M6/A14 to rockingham. i'd been cruising along at 4000rpm then on the A14 i started going up a hill and it was trying to comk out, the boost gauge was reading -10 still, the wideband went off the top of the scale, ended up crawling up the hill in 2nd gear with very little throttle. pulled into a petrol station and disconnected my IC piping and ran it to the rock basically n/a so it wouldn't use any extra fuel.

while i was there i took out the pump pre-filter and stuck a piece of copper pipe in its place, reconnected my IC piping again. then on the way back up the A14 it started the same again, even though i'd already had the car at full chat @ 12psi all the way up into 4th at around 5krpm without a hiccup.

pulled over again and disconnjected the IC, then halfway up the M6 it started doing it again exactly the same, just crusiing along then when i went uphill so had to accelerate slightly it leaned right off. pulled onto the hard shoulder, sat there for 5mins and checked a few things then crawled at 2500rpm all the way home.

I've checked the breather pipe from the tank isn't trapped kinked etc so the tanks not getting an air lock, no wooshing when i open the filler cap either.

I think i'm going to rip[ the carb off in the morning and see if i can make it work properly.

any other suggestions?
sorry for the long post

When you say the WB went off the top of the scale, I assume you mean lean ?

Could there be a blockage at one of the openings of the carb, that lead to the float bowl ?

The one that pressurises it has a very small restrictor in it. Part of the part throttle lean setup. ( rubber hose that links float bowl to throttle plate )

Perhaps if teh restrictor was blocked, cruising in vacuum for a while might create a vacuum in the float bowl, making it almost impossible to draw fuel ?

Doubtful, but worth a look if all other avenues have been exhausted.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Is your fuel pipe getting hot anywhere along it's length?

The fuel could be vapourising in the pipe causing a restriction.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

my part throttle lean off pipe has been blocked off either end for the past few years. checked all the hoses for splits leaks, and replaced them xmas to be safe anyway.

i'll give the carb a blast through with the airline when it comes off aswell for good measure.

the fuel pump is mounted on the rear subby, its fairly close to the backbox, but its been in the same place on my other car for years, i have been tempted to make a heat shield for it though.

get a gauge on the inlet to the carb drive it and see what happens to the pressure .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

just been out trying that and the pressures only dropping about 0.5-1psi when it happens. We've checked the float and its set fine, changed the needle valve for the brass one that was in before it got rebuilt although they both looked the same size.

its happening a lot later now though, only right at the top end (5k) of 3rd, then change to 4th and its the same again. haven't had the time to take it on another motorway run though to try and recreate the problem when cruising, will give that a shot one of the nights in the week.

its really stumped me and kean though as we can't figure out what could be casuing it now.

the one thing i did want to change while we were in there was the bi-metallic jet holder but my mates got my welder at the minute.

i had the same prob ,with mine had to sit halfway nup the hill out of cheltenham last summer after a trip to the lord herefords knob hills ...turned out to be blocked filter before the pump ,then duff pump then leaking fpr diaphragm ,then duff capacitor,and so on , that fuel pressure shouldnt drop at all really ,it should always be above boost by the same amount or more than the tickover setting ,hmmmmyou could try turning up the fp a bit and see what happens .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

yeah, i think the pressure could be dropping as i'm backing off as soon as it happens rather than something else causing it to drop.

might nip to halfrods and get a new lo-gauge cos i think we fooked this one trying it out this morning. the needle doesn't point in the right direction anymore, lol.

If its a fuel pressure issue, I wouldnt be looking at the carb.

Fuel pressure is pretty much dictated before the carb ( it only goes as far as the needlevalve.
And for pressure to drop, the needle valve would need to dump some serious fuel in !!!

Sounds like a fuel supply issue for some reason. Could there be anything blocking the fuel pickup in the tank ?

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

the thing thats been really bugging me throughout this is how loud the pump is like its struggling, the new one sounds exactly the same.

i'm running the fuel down in the tank at the minute, should be pretty low when i get home from work tomorrow. i can't see how anything could have gotten in and blocked the pick up but i've got a feeling the tank will be out for a checkover tomorrow night!

Here's a quick test before you take the tank out. Probably too late.

You need your pump to be pumping around 1 litre/min. This is easy to check by taking a pipe off, turning the pump on for, say, 20 seconds then multiplying the amount pumped by 3 (sorry, granny, eggs and all that).

What might be of more interest though, is doing this test at a number of different points in the fuel supply and return system.

1) Before the Regulator
2) At the tank end of the return hose.
3) At the carb (might have to block the rtn for this to be of use).

If there is any difference in the result, it might help find a problem.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

i'll give it a shot wil, at this point i'm willing to try anything. got to get the car running properly so i can drive to newquay on friday!

Have you double checked any solid lines for kinks/crush marks? I had almost the exact same symptoms on my old clubman estate years ago, turned out to be a slightly kinked solid fuel line. Replaced this and it went away.

I know very little about this kind of stuff... but, the only thing that's made a significant improvement so far was playing with the carb. I rebuild my carb last weekend and have a box of bits i stripped off. If it helps, i can slap them in a jiffy and send them to you to swap and play with. Don't think i've got a spare bi-metallic though, will check tonight for you.

cheers for the offer dude but i've got all the bits i stripped off this one still in the garage (im a hoarder, lol) i was going to ditch the bi-mettalic holder for one of the solid ones i had off Dan ages ago.

Tom i've got to check the lines where they come up between the rack and subframe but everywhere else they look fine.

I ***think*** we may have cracked it, yet to give it a proper test as i keep running out of road, but up to the limiter in 3rd its still pulling hard.

tonight kean came and gave me a chuck again (much appreciated dude!) We tested the flow rate by taking the pipe off the carb, it filled a 500ml pop bottle in 11 seconds so easily satisfies the 1l/min that wil mentioned. then we swapped the plenum>reg hose to be safe.

then whipped the fuel tank out, washed it all out got rid of some smeg in the bottom and noticed the std filter still on the pick up pipe. bashed that off and it looked really grotty and caked in shit so couldn't have been helping things.

the pump now sounds a bit quieter but i've yet to stick a pre-filter back in. Going to see if i can give it a proper run up the motorway tomorrow night to test it all out properly.

Cheers for all the advice, tips etc dudes so far, fingers crossed this ones sorted now

just been out for a quick pootle round and the car doesn't lean off at all now, managed to try 4th gear out and it just keeps pulling, wideband says yes too so i think its all good now

just got me fingers crossed its ok on the way to newquay now!

thats another reason why i used a tpeice rather than a tank return, as with a tank return the outlet needs to pass all the fuel the engine wants plus excess of the return from the pump, but with a t piece infront of the pump the tank outlet will only ever need to pass the fuel requiered buy the engine.

also i used a ford focus filter after the pump and not before, as the pump will pass very small bits of shit that you can get in fuel but the filter will sort it out before getting to the carb.


but glad you have got it sorted out mate

always looking for them bigger bunches of bannanas

wow my head just got even bigger. lol
i had the problem with the filter in the tank and found i could only get 500yards down the road and it would try to stall. stopped for a bit then could get about 200yards

just to add the filter in the tank is even fitted in the vans and estates, i cut the top of the van tank open to remove it. i had to do 2 tanks as the first one went BANG!

hehe, yeah we had the same thoughts, couldn;t find any circus folk to get their hands in the tank so opted for the long screwdriver and a hammer method of removal.

I'd say thats why me and kean didn;t have any issues when using the T piece return method, i used to run a totally std tank with the little outlet pipe and filter etc. keans still running fine on a std estate tank aswell with the T'd return.

Excellent news, good luck for newquay.

-MINI CLUBMAN 1380 TURBO-

Id be concerned about heating the fuel with the T piece method...


If using a rpe-filter, make sure it is large enough to cope with an efi flow rates.

Most efi pumps will flow well in excess fo 1litre/min mentioned above, and some can easily be 3 l/m, especially as turbo carb cars run relatively low fuel pressures.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Great. I had leaning out last year on the rollers as well, but I do think I've got an early tank. I don't think these have filters. Is this correct?