Old VW camper running problems

[Noddie]

my mate has an old VW camper and it keeps momentarily dieing and then over revs and backfires when he puts his foot down to combat it, it also over revs sometimes on idle but then other times will only start and idle for 2 seconds before dieing again, i cant think what the problem is but before i take his carb apart and start changing the coil and dizzy and stuff i thougth i would ask it anyone has any ideas?

oh, and its not the fuel supply to the carb as i have already checked that.

thanks for any help guys, there is a reward of 7.5 points to the person who gives information that leads to the solving of the problem
Ed

 

[solarice]

Dont know much about the common faults tbh...but id be looking for vac leaks and ignition faults. Easier just to work backwards from easiest to hardest possible solutions.

My K10 used to cut out at idle etc (though no backfiring) and that turned out to be a carb fault...

 

[frank]

its usually the points on those things ed (damn fickle they are :suspect

 

[Noddie]

thought you might be able to help frank
dont think its vaccume as it just dies and then comes back to life like normal, i will check the points then, could it be coil? dont they start to get intermittant when they start to break? i was thinking that the backfire might just be no spark then the fuel exploding in the hot exhaust. i will check out the dizzy then;D
thanks for the help guys!

 

[frank]

i think coils tend to break down more as they heat up ed, my daughter,s was running on 2 because some clown had opened the boot and swapped 2 HT leads over :glare: (2 downpipes were stone cold) more likely the points tho imo, the dizzy shaft gets a bit sloppy and scatters the 4 gaps, try various points gaps (10 thou", 15 thou" etc)