Mixture screw

[casper]

Hi all.Is it normal for the mixture screw to blow out sometimes.One minute its there idling fine the next its vanished.:confused:

[Benjibrady]

Mine did. Bought a couple spares from Renault. Some people seal them in.

[casper]

Thats cool then.I have a spare so i will put it in tomorrow.:agree:

[Dave Reed]

Ye sill it up with a bit of silicone.. They always seem to do it lol

[casper]

Thanks for the replies guys.Bloody carb is not playing ball since i reb:cry:uilt it.

[Brigsy]

New mixture screw should be ok. It will come out time and time again though if its hanging onto the last couple of threads in the hole. If you need to wind it all the way out you may need to change the idle jet size so the screw can be wound in more. I had to do it with a hot cam.

[casper]

Before i rebuilt the carb Jon the mixture screw had to be almost all the way in for an idle of 14.5 which is where it was best.After the rebuild it had to be almost all the way out which like you say is why its blown out.Bloody thing is lean at wot now as well and theres a problem in 4th with it leaning out too lo:confused:w in the revs.

[Dave Reed]

Maybe you've got an air leak from the carb overhaul? Bit of easy start will show you that.

Or a possible leak in the exhaust system making you think you are running lean..

If your friendly with your local garage maybe pop down there and get them to check with their gas analyser.. After all it could be your sensor playing up to

[casper]

Just been out trying to solve the problem.Boosts fine in 2nd and 3rd full boost no problem with the afrs.Then in 4th as the boost really starts to build the afrs go really lean(16s).Does this sound like an air leak?

[BluntyR5GTT]

could be the carb bowl emptying fella?

[Goobie]

Little trick I used to do on mine was to slip a short bit silicone vacuum hose over it with a screw in the other end as a bung so if it did pop out it would be in the vac hose. :cool:

[casper]

could be the carb bowl emptying fella?

Yeah i did think that also Andy.Although it was fine before i rebuilt it.Possibly a faulty needle valve?:confused:

[michael tierney]

make sure ur idle jet is tight(maybe use old rubber ring)as the new rubber ring sometimes stops it from going home all the way:)

[casper]

Idle jet is tight Micheal so much so i cant get the pesky thing out now.lol:confused:

[casper]

Could it be a missfire thats showing up as lean on the afr gauge?or would it missfire in 3rd gear as well if that was the case.:scared:

[Jonny5]

A misfire would show as a sudden lean, yes.

[casper]

I had been thinking that the sudden leaning was the cause of the missfire but thinking about it the leaning may be because of the missfire.:agree:

[casper]

Right guys i changed my plugs today as i thought the misfire in 4th was down to these.Anyway i changed them then took it out for a quick blast.Hey presto although a little lean(12.5) wot the misfire had gone.Tried it a couple more times and all was fine.One more try on my way home and it was back.About 5k or so in 4th it starts to misfire again.Obviously afr gauge shows lean in the misfire which is what threw me when it first happened.Any suggestions?Do you think this means i can rule my carb out and it is infact an ignition problem.:confused:
car has new;
Bougicord ht leads
Bougicord king lead
dizzy cap
rotar
plugs

[GTphil]

The only thing missing from the list now is the tdc lead, sometimes they breakdown but appear fine on the outside. Often this causes weird missfires

Hard to tell if it's carb or ignition related. Seen as the issue wasn't present before you re-built the carb like you that's where I would be looking.

Can you not borrow a known working carb and stick that on to see if it cures it?

[casper]

I just assumed it was the carb,especially after i have just had it completely stripped but the new plugs did cure the problem for a short time.:confused:

[phase i 16 v turbo]

Carb mixture screw OE seal

http://www.gt-turbo-spares.co.uk/cart/index.php?cmd=view_image&prod_id=472

[casper]

Could you send me one of them as well please.:agree: