carb problems?

[murf]

Sought help here before so here I go again!
Van was running fine last year, on the way back from vanfest, everything fine until I stopped for fuel, then she started missing and struggled home. It felt like fuel starvation?
Just had her serviced, new ht leads, plugs, oil, all filters, coil, dizzy.....still runs like a dog.
To be fair when Elite put replacement engine in approx 3 yrs ago I was told one of the carbs was pretty worn.
Is this the cause of the problem?
If so, wheres the best place to get replacements (ie cheapest).
Im no mechanic so carb rebuild kit wouldnt be much use to me.
Shes 1982, 2l, Aircooled, cu engine.
Any help would be greatly appreciated

murf

[BOXY]

still runs like a dog

Something a bit more specific might help the diagnosis?
Could be timing, blocked fuel filter, vac line fallen off, balance pipe disconnected, any of the electrical connections on the carbs etc. etc.

[murf]

Hi boxy

Timing done not long ago, all filters are new, fuel getting to carbs ok, but definetely not firing on all cylinders.
Starts ok, but keeps "putt putting" and when I drive her, keeps missing, especially when you put your foot down, IE taking a run at a hill !
Its as though fuel not getting through when its most needed.
As I say, im no mechanic,but the guy that looked at her could only come up with carb problems and decent vw mechanics are like hens teeth round here.

murf

[kevtherev]

is it better or worse when cold

[Ian Hulley]

If it's missing under load it could be the coil ?

Ian

[BOXY]

The procedure below was hand-written on the inside cover of my Haynes manual. This will let you set up the carbs without a gas analyser. Have a check to make sure the vacuum pipes are all still connected as well. If it's not firing on all cylinders I'd be tempted to take the plugs out and find out which one isn't firing and see if that points towards a possible cause. (wrong gap, oiling up, broken electrode insulator?)

First, run the engine until it reaches normal working temperature, say 10 to 15 minutes, then switch off. Remove air cleaner for access. Next, check that the balance pipe rubber connecting hoses between the 2 inlet manifolds haven t perished or are taking in air. On each carb below the electro-magnetic cut-off valve is a mixture screw. Turn both in all the way, then back off each 2.1/2 turns. Now restart the engine still with the air cleaners off. Adjust both screws slowly in the SAME direction until the engine runs at about 750 rpm. Next, remove the right-hand magnetic cut-off valve live connecting wire, listening carefully to the drop in revs. Then reconnect. Do the same on the left-hand side, again noting the decrease in revs. If the rev drop is different, this proves the mixture is incorrect on one carb so adjust by small amounts both mixture screws until the speed drop is identical, with each magnetic cut-off valve wire removed in turn. This all requires patience and takes time to get correct but if is important and well worth the effort in the end.
For the final stage and with the engine running, concentrate on the left-hand carb, on the top of which you will find 2 screws. The right-hand one is the actual idle speed control which must be turned until the engine speeds up to around 900 rpm. Next, turn the smaller left-hand screw a little in both directions until the engine runs smoothest. If the carbs and the engine are all in fair condition, this should be as good as human hands and ears can expect without expensive special equipment. I must stress that this is only a very abridged and simplified description for home tuning and will not, of course, provide worn out carbs with a new lease of life. Even so, it is well worth while for, in 9 cases out of 10, the main problems we find with these twin carb engines is mal-adjustment of the carbs. Providing the above method is carefully followed, a fuel consumption of not less than 20 mpg should be obtained.