bloody carb

[LYNCHSTAR]

running 18 psi with standard venturi 1.2 main 1.0 a/c 1.3 2nd 1.7 idle jet after screwing mixture screw in all the way and unscrewing 3 turns it ran like a bag of ****e after screwing out nearly all the way i finally got the afr,s to 14.5 idled great took it for a spin afr,s in high 11,s on boost and 14.2 at cruise. then when cars stationary the afr,s drop to low 12,s then i screw the idle screw back in to get 14.5 take it for a spin drives great then have to set afr,s again. when cars of and go to start it again it struggles to start black smoke comes out exhaust like its over fuelling. any ideas guys :confused:

[R5TURBORON]

Make sure you haven't snapped the tip on the mixture screw. Take it out and check

[Thundercat]

Sounds like may be there'd some crap in the carb, good blow out with carb cleaner.

[TNT ANDY]

Firstly, make sure that your throttle is closing fully when at idle. We had this problem over here last week and was finding it a pain to find the answer, but it appeared that the throttle was slightly open @ idle causing the idle feature to be mainly redundant.

[THE MASTER]

if you got silicon hoses make sure the rebreather jet in the hose that goes to the rocker cover from the manifold is a good sealed fit. in some silcon hoses the jet is way to loos and floats around.:coffee:

[LYNCHSTAR]

if you got silicon hoses make sure the rebreather jet in the hose that goes to the rocker cover from the manifold is a good sealed fit. in some silcon hoses the jet is way to loos and floats around.:coffee:

had a run in it tonight and it idles in low 14,s when going for a drive on boost full throttle it drops to low 10,s. head ache.:mad: i might have to get the 14lb hammer out.

[LYNCHSTAR]

if you got silicon hoses make sure the rebreather jet in the hose that goes to the rocker cover from the manifold is a good sealed fit. in some silcon hoses the jet is way to loos and floats around.:coffee:

Hi there I don't have one way valve i blankt it of with m8 bolt and copper washer. Bloody afr,s drop to mid 10,s on boost now do I need to change the a/c I have a 1.0mm.

[Jimmy_GTT]

Check:
- sealings between carb body and throttle body, throttle body and inlet manifold
- throttle shaft doesn't have to much play vertically in the throttle body - green O seals are also good
- throttle plate (if it has been removed) is fitted back the correct way into the shaft
if the idle screw is fully turned out the throttle plate should fully close the vertical slot of the progressive transfer
- and there could be some dirt in the carb
I've just bought a little yewellery ultrasonic cleaner which is just big enough to put a carb body in, and some ultrasonic cleaning liquid specially for carb cleaning. I'll try it in the next days and present you some pictures in my carb topic.

Try also to change the needle valve. Check if it has the correct 1mm washer. And maybe the O ring under the accelerator pump jet.

[Jimmy_GTT]

Hi there I don't have one way valve i blankt it of with m8 bolt and copper washer. Bloody afr,s drop to mid 10,s on boost now do I need to change the a/c I have a 1.0mm.

If idle is fine now, you could give a try with a std. a/c.
My previous post is for the changing idle afr.