carb mixture / running
Turbo Mini Forums

hi all, have any of you guys come across the carb / engine still running lean when the mixture screw is right in? i just cant seem to figure this out. there is no air leak found as yet, it was running fine before x mas since then i have changed the turbo and not really had her out.

what i have done so far,

rebuilt carb (checked and then checked again)
changed all inlet gaskets and manifold gaskets twice
re seated and checked all valves ( all are ok )
new head gasket
new ignition module ( just incase )
new spark splug`s ( just incase )
ht leads are all fine
new earth lead fitted ( just incase, starts better now any way :) )

forgot to mention, fuel pressure is set up at 4 psi at idle and it rises with boost. also tried the T piece trick but i know i have the right gasket as i fitted it :)

Has the needle been re profiled for the new turbo? are you running more boost now? what dash pot oil are you using?

Edited by MarkGTT on 8th May, 2010.

hello mark, i am using a standard BDD needle and running standard boost. i currently have 15 - 40 in the dash pot, do you think it is worth going thicker?

When is it lean?

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

all the time, it wont run very well at all. i have put a color tune on it just to set it up to get it to a r/r but it is running lean on tick over and if you go for a drive it splits and backfires a lot.

plenum gasket on the right way round?

Sounds like the jet might be being obstructed.

If there is actually fuel in the float bowl and fuel level in the bowl at a sensible level, you could still drive it for a short distance even if you had no pump.

So clearly there is another fuel supply problem.
I dont really see how a jet could be blocked...but it is possible. Or needle somehow stuck in the jet.

Or as mentioned, carb mouth gasket if used blocking the float bowl vents.

Will it run with the choke in ?

And was the problem there before YOU rebuilt the carb ?

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

you've certainly fucked something, let it for today, come back tomorrow after a good night, then look after what YOU have done, it'll jump on your face

cheers for all the suggestions, i think i will strip the carb down and change all the plenum gaskets well, when it stops raining! the problem was not there before the carb was rebuilt so the problem must lie in there somewhere. see i keep thinking there is an air leak but i have checked and checked and checked :(

Might be the bi metalic strip fitting badly that is stopping the adjustment

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

i think i have found the problem, the inlet manifold is not the standard one, i measured the thickness of where the bolts clamp to and then the thickness of the exhaust and found the inlet to be smaller, so it is not nipping it right up. so it is an air leak. i just used two gaskets, cut the inlet sections out and put it together with both gaskets and hay presto.... bit of a bodge but i know what the problem is now :) i am so chuffed! thanks for your comments tho guys

if i get a chance i will put a photo of my inlet up on here tomorrow see if any of you lot can tell me where it came from, i have not seen one like mine for sale at any mini specialist or on any mini as yet

Kerwin, i would get a standard turbo manifold leyland did there homework on this one and got it RIGHT!
with the fuel distrabution.