Hi everybody.
I got a 32/36 Weber rejetted and re-conitioned and fitted it to my A15 standard set up with extractors and electronic ignition.... It Goes very well.......Except from low revs or from start off where it hesitates on take off. You need to rev it or slip the clutch or it stalls.
I took it to a carby bloke and he reconds that it is too BIG for the engine and at low revs the engine does not suck enough air through the venturi fast enough.
And that it will allways happen. Has anybody had the same problem and been able to overcome it ?

thats a load of crap about it being too big cos i run a 32/36 on my a12 and it doesnst have any hickups

I reckon they have jetted it too lean to meet emissions or you have something wrong with your advance curve.

Quote:I had a Weber Italy 32/36 on my A14 and it didn't do that. I had a bit of a flat spot, but it never, ever, wanted to stall.

Sounds like a vacuum leak, but it could be something else. Most cars I work on that are 10 years old or more -- regardlesss of brand -- have a vacuum leak or two. The only way to rule it out is to thoroughly test all vacuum hoses, sensors and diaphragms.

As far as the carb goes, visually check it for a strong and steady pump stream.
Accelerator_Pump_Test

and for overview:
wiki - 32/36 carburetor

Thanks Guys for all your helpful advice.
I will check it out.
Oli

i had a 32/36 on an a15, never had it rejetted and still worked like a dream (with the occasional puff of black running rich smoke)

would go for vaccum leak or possible carby issues. is the float ok in it?

sounds very much like accelerator pump, it squirts a quick jet of fuel in when you first hit the accelerator,
just to ensure there is enough fuel when you open it up to so much air all the sudden

if it only stutters (for say one second) when you first accelerate i would guess that

get someone to pump their foot on the accelerator, with car turned off and see if its squirting fuel into the carb each time

if its not its probably the diaphram, you will see the accelerator pump working away while the throttle is pumped on the bottom side of the carby (can be on either left or right side but should be towards the front)

there is a little arm that pumps up and down, if you take the four screws out where that arm swings there is a little diaphram in there

good luck

Thanks guys for all your help.
I went on an overnight run with my club on the weekend. On the way out it played up big time. 1/2 way there all the learned home mechanics had a look at it and confirmed what you guys had told me. An AIR leak, we found that the adaptopr plate Grub screws had worked lose. So at the next stop I removed the carby tightened the grub screws (Still yet to locktight them) and away I went. This cured the hesitation, the over run when switched off, and improved fuel economy from 21 mpg to about 32mpg. BRILLIANT. So all the helpful info given on this site was spot on.

Now the only problem I have is, I can't get the choke to be FULLY closed, its only open about 3mm but when cold its enough no to start it & I've got the idle down as far as I can but still revs at about 1500rpm on idle and the mixture screw will not slow it down either, its almost all the way in, the slowest revs I can get.

Do you think I need to look at the timing?

Thanks with ALL your help guys.
Oli

Quote:This has nothing to do with ignition timing.

Do you mean that when cold, before you start the engine, pump the acclerator pedal once and then look at the carburetor. The choke should be fully closed, cutting off the airflow.

If it is not, and this is an automatic choke, simply rotate the choke housing until it just closes fully. Then tighten the screws for the choke housing.

Quote:This is correct when the engine is cold and choke is operating.

Thanks ddgonzal
But I have a cable operated manual choke and I've tried adjusting it further but this only seems to raise the idle further when warmed up.

It seems it does need to be FULLY CLOSED when cold to start.
Is this how they all are?

Also the 1500rpms is when the car has warmed up. That is the lowest irt will idle.