Loosing the will

Hi ive had and still have alot of old vws but my mk1 is pushing its luck at the moment as ive yet to have sucessfull journey .The problem im haveing with it is it starts straight away as ive fitted a brand new webber carb conversion with manual choke but when driving it looses power and wont rev and stops but will always start again but revs once the dies again this will happen about 15 to 20 times then it will start and drive again but will hesatate then pick up again the hesitate until it stops again.The car is a 1500 gx so has the return pipe to the fuel tank does it need this with a webber as it may be returning to much fuel and starving the carb.Its had everything replaced including the fuel pump.This said it can run for about 20 miles somtimes before the problems start again this morning it took 45 minuits to go 6 miles any help would be good
Cheers chris

Debris in fuel tank/fuel lines causing a blockage or no warm air pipe to carb causing icing?

I had a problem like this with a carb, the dizzy was soaking wet so look there, then the above, then air/vacuum leaks. 

have you got the standard air box on or aftermarket filter on the carb

carbs do not need a fuel return line. i would delete that.

did you replace with a suitably specced fuel pump rated for the carbs? and also check according to previous comments.

sounds like a fuel/air or spark issue.

stick with it mate… it will resolve itself.

Don't give up mate. Take a step back, have a beer and relax. All will be sorted.    

Well the tank is clean and the pick up pipe is clear so tomorrow imgoing to remove the fuel return system as all my other carb cars just have a pipe from pump to carb so i dont see the need for a return pipe on a carb car.See if that works have decided if its not sorted by the weekend its got to go sad but i need a car thats going to work back to aircooled i think nice and simple
Cheers chris

it may sound daft but what air filter are you running? i ask as it sounds like you are suffering from whats known as carb freeze

I've got exactly the same problem….feeling your paincf_emoticons__BangHead:I don't drive mine daily but only have had it 2 weeks and thought it was perfect- now systematically changing the ht, dizzie cap, plugs, fuel pump, filters and cleaning out the tank of the crud (that included a snail…and this car ain't no barn mobile) and next I'm doing the vapour seperator….hoping I'll get there in the end…

Interested to see how you get on tapping off the return pipe….will be next on my list.

Good luck!

Is it taking warm air in?
In my mk2 'rocco days, I used to have my weber on a stock airbox, but with the flap removed, so in winter, I blanked the cold air inlet altogether, ran both cold and warm in spring/autumn, and just cold in summer. Worked a treat!

I also had an issue with too much fuel returning to the tank (low pressure at carb) and restricted the return pipe down to 1.6mm. This happened to me only AFTER I changed the "swirl pot" for a new one.
  

Right heres where im at i had a chat with a weber expert about the fuel return and he said not to remove it as the fuel pump does not have a pressure relief valve so the carb will see to much pressure as a weber shouldnt have more than 3 psi.Weather this is true i dont know so ive left it.I have now replaced every ignition part including plugs leads points condenser and dissy cap and coil also noticed the fuel pipe from the inline filter under the bonnet to the suction side as the fuel pump had started to colapse so i replaced that to. Pipe was only 4 months old now has injection quality pipe.Also when i removed this pipe it was bone dry and i had driven the car across the carpark into the workshop which i thought was strange.Then i went for a drive and it went 10 miles no problems loads smoother so happy days dont know what part was at fault but hopefully all sorted now.

glad to hear its better mate

Fingers crossed its ok as its a nice car would be a shame to get rid of it

Good news Chopper, well done for perservering.  

I had this problem with mine too mate. Nearly drove me to drink trying to get it sorted    As said, you step back take a break, and come back to it, a solution always promotes itself. Mine was a fuel tank full of water! They dont run very well on H20….I wish they did!  

Chris