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hi my golf syncro is playing up again it is on a weber carb. when she heats up and is at operating temperature and you push the choke in sometimes she will cough and splutter when you are on the first choke but if you floor it and go to the second it is fine. she is also stalling at junctions. anyone got any idea what it could be. it is impossible to drive at say 70 mph because the engine is spluttering so much it feels like it is about to jump out of the engine bay. the starnge thing is that my m8s jetta syncro is exactly the same thing. any ideas? im guesing it is carb related
Have you got the original VW air intake assembly fitted? if not then your carb is icing up, refit the original intake assembly & it should cure it.
hey there yeah i do have the original air intake fitted but come to think of it when i touched the carb the other day looking to see if any vacumes where of it was ice cold is there any other way of stopping the carb icing up? also why does it ice up when the engine is hot?
also when it happens the throttle gets alot stiffer to depress and is slower to release is this another simptom of carb icing?
I am sorry I dont know, I’ve got injection, but it does sound very possible.
Here are some links,
http://www.vwsyncro.co.uk/data/forums/topic.asp?TOPIC_ID=1869&SearchTerms=carb+icing
http://www.vwsyncro.co.uk/data/forums/topic.asp?TOPIC_ID=1869&SearchTerms=carb+icing
The webber carb dosen’t ice up no where nearly as easily as the pierburg did.
Every winter there is all this stuff and ppl squeeking about carb iceing it rarely ever is, I had my webber ice up once that was one hell of a cold day cruising down motorway at relativly low throttle and high rpm which is what will ice a carb up
carbs ice beacuse at low throttle as air travels through them past the butterflys it is forced to expand and when a gas to expand it’s temperature drops hence it gets cold, if the air coming in is cold enuff and you make it expand it becomes very cold and and any water in the air freezes out, it’s also possible to get the petrol to freeze as well which chokes the engine and it’ll chugg to a halt. a bit of full throttle will normally clear the carb or in severe cases pull over and leave it 10 mins.
I would suggest checking the primary jet for ****e and fitting an inline filter right by the carb
which is the primary jet and where is it located is it the brass jets 4 of them on inbetween the two chokes as you look down on the carb? and check it for what shall I just blow them out with an airline and also i have a filter pretty close to the carb allready and it is brand new.
iirc the center two are the main jet assemblies, the air corrector top bit has a small hole in it, unscrew the assembly and draw it up out of the carb sometimes the jet right at the bottom can become clogged with crap, the normal cause of this is the fuel reservoir or whatever you want to call it thats mounted on the front of the rocker cover, if it’s a new carb and allways had filter dirctly inline with it the jets should be fine but worth checking
Is there a vacuum line connected up to the connection halfway along the air intake pipe?
and is your exhaust manifold warm air intake intact? or has it rusted away as they all seem to do, either of these will affect the running in low temperatures
yeah that is all in tact i made sure of thjat thinking that it could be that. i realy think it could be carb icing tho because if i drive her sensibley she is fine and will not stutter but if i drive like a looney it will couch and splutter after wards when i calm down lol.
Is the connection for the manifold heater under the intake manifold still intact? Without that it might mess things up a bit.
yep that is all conected and works fine as it gets hot when ignition is turned on.
plays up straight away or after a while ?
it may be worth connecting the pump directly to the carb and bypassing the fuel resovor ont he frount of the enigne and blocking the return pipe up to see if it makes any differance. the webbers can tolerate been connected directly to the pump tho it’s not ideal ( perburgs don’t like it tho ). if it still dose it may well be carb iceing
its worth checking all vacume lines are connected and intacted and i would suggest taking all of the jets out (make a note of where they went) take the fuel intake pipe off, and remove the mixture screw, get a can of carb cleaner and blast it through all openings. iam also having the problems in the morning cutting out etc my theory is that my powersteering pump is going which is seizing causing there to be a load on the engine causing it to need more revs, but when you let the choke in it stalls the engine as it doesnt have enough revs to maintain that load.
I’ve got a powersteering pump sitting on a shelf, if you want it.