Yet another carb issue

[matt1334]

Hi after reading loads of issues regarding the set up of a carb I am still at a loss.

I have rebuilt the carb following the instructions on the guide, only thing I forgot to do was the accelerator pump adjustment, I have removed the elbow and it does seam to squirt a nice stream, however the problem I'm experiencing is on tick over the engine revs up slightly on its own.
I have read possible air leak, but where could this be?
Also my vacuum reading is -10 does this sound ok?

I am going to invest in a aem uego so hopefully this will tell me more, but was wondering if there was a way to find the cause of this in the meantime.

Thanks matt

[bigdavec1974]

Hi mate ,
Your idle is hunting up and down?
Have your checked and replaced the rubber seals on the lobster and idle jet ?

[matt1334]

Hey Dave yea that's what's happening

New lobster
New o ring on carb top
New idle jet o ring also

[bigdavec1974]

Got a can of easy start or wd40? Go searching for the leak. Spray on a joint and listen for Rev pick up, if there is you have found a leak. Vacuum pipes all plumbed back correctly?carb base has seals and tightened up correctly ?

[matt1334]

Il give that a go

All pipes seam in place did notice no clip on the inlet breather hose tho, although it feels tight

Looks like a Sunday in the garage (heaven)

[francob80]

New poster! (less than 10 posts)

Mine was acting up like this recently, changed mixture screw and ensured that idle jet was cleaned and tightly sealed. Problem disappeared and now runs spot on.

[matt1334]

Just noticed when the car is warm no chock and the car is hunting on idle the piston in the dump valve is moving, is this normal?

[bigdavec1974]

Is the choke operating correctly? Dunno about the dv, don't have one, I like my engine

[matt1334]

Haha yea choke seams to working correctly

[bigdavec1974]

Tried removing the dv? They can leak especially the piston types.

[matt1334]

Dv removed still the same, cleaned idle jet also

[Ian S]

Could it be your Renix ECU? When they are knackered, the idle does go up and down all the time.

[matt1334]

Ok update removed carb only to find that the mixture needle has snapped in the carb base.. Any idea how to remove this?

[bigdavec1974]

Removed mine from the rear I seem to remember, was about 15 years ago mind u lol

[matt1334]

Done it although it looks like the thread on the base has stripped

[bigdavec1974]

Just replace the base, there are shit loads about.

[Trevhib]

with a new base gasket

[Leloby]

Those idle O-rings can be dodgy. They are too big and rubbery and you don't get a hard tightened seal. Not sure if even the "genuine Renault" ones are actually meant for the idle screw on a 32dis...

What I found is they do seal, but they make the jet sit too far out and idle, afrs and running is affected. Flat spots and hesitation. The screw even rattles loose eventually. Took me ages to work it out.

Best to get a smaller butyl o-ring and stretch it over. Then the screw will fit tight and not undo.
Worked for me anyway. £1 shop o-ring selection has them. Might not be the proper rubber but they do work - 1year on, no trouble.

[matt1334]

Nice one , however need a carb base me thinks looks like the thread has stripped gutted but just one of them things
Where can I get the orings

[Ian S]

Carb bases were that part everyone needed and no-one had, as they all wore out, warped, or had your problem.

[Ian S]

Those idle O-rings can be dodgy.

Is that the idle jet seal or mixture screw seal that's dodgy?

The idle jet seal in RTOC kit is one we source ourselves and add to the kit as the kit from Webcon (or Webber?) doesn't have that included.

I presume that it's the idle jet seal? If so, would that (those) be from RTOC, or the original, or some other source?

[matt1334]

Hi Ian its mixture screw however it seams to be in place so I am in the process of rebuilding

Fingers crossed

[matt1334]

Success

Have no idea what it was
1 mixture screw replaced
2 new idle jet
3 accelerator pump adjustment

All I know is it's up and running, but another problem now
Don't ya just love these frenchies

[bigdavec1974]

Excellent ! 😄

[Leloby]

I presume that it's the idle jet seal? If so, would that (those) be from RTOC, or the original, or some other source?

Yes, seems to be from wherever I buy them. Even the gen Renault bagged ones from CGB are too big and rubbery. They don't work for me anyway. The car type part of the label is always ripped off so I suspect they're for a different car/carb.