Adjusting 34PICT-3 help please

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davla

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So I've read all of the set-up guides but having trouble adjusting carb correctly
- Volume control screw is set 2.5 turns out
- Bypass screw is set 2 turns out
Engine ticks over nicely but when I pull away it splutters and tries to die, so I have to drop the clutch and rev the engine to get it going to pull away which is very frustrating, it seems too rich to me
Timing is set correctly and have original air box
Any ideas please? Does screwing volume control in make mixture leaner on ticker?
 
What distributor do you have? If it's a 009 it sucks and will flat spot, does it have vacuum advance SVDA

Makes a big difference if you've got the right dizzy, also old/dirty fuel can cause problems

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Some very good U TUBE films on this subject. In work at the moment otherwise i would look one up for you. Just a thought and a very long shot. I had an issue with brand new HT leads i am tone deaf so couldn't hear the van was only firing on 3 cylinders. Only found out when i removed the plugs and no1 was brand new. wondered why my my timing light was playing up :roll:
 
Is the vacuum tube connected correctly? You may want to look at the timing and ensure you have the correct position of the distributor based on your engine

http://www.aircooledvwlove.com/how-to-set-ignition-timing-on-an-air-cooled-vw/

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If your car has been sitting for a while and has been unused strip carb down and check all the jets for any blockages. Also see if there is any corrosion (white/grey deposits) in any of the jet chambers. This is caused by fuel and moisture reacting with the body of the carb especially if it is a pre unleaded era one. I had a problem with mine as car was sick as a pig and once I cleaned (blocked jets) and reassembled it was like a different car. Check accelerator pump for leaks which feeds the accelerator jet. Now look into carb and open accelerator with engine off! and you should see a nice squirt of fuel coming out of this jet fed by the pump as mentioned. If not, its blocked. A small ultrasonic bath is a good tool for cleaning.
 
davla said:
So I've read all of the set-up guides but having trouble adjusting carb correctly
- Volume control screw is set 2.5 turns out
- Bypass screw is set 2 turns out
Engine ticks over nicely but when I pull away it splutters and tries to die, so I have to drop the clutch and rev the engine to get it going to pull away which is very frustrating, it seems too rich to me
Timing is set correctly and have original air box
Any ideas please? Does screwing volume control in make mixture leaner on ticker?

Check your connection to the fuel cut off sov on left of carb is not loose and intermittently giving you fuel starvation. Iv seen that happen. final check would be the fuel pump. Check by disconnecting pipe to carb and get someone to turn over engine. Put pipe into a can and see if there is a good flow. Remove dist or disconnect wire from coil that goes to dist so car does not start !!.
 
Rather than running rich, I think you might be running lean. Not lean when at idle, it at constant revs, but lean when you suddenly open the throttle.

The square diaphragm mentioned above gives a squirt of fuel to deal with a sudden throttle opening and you should check out that circuit. It runs from the diaphragm along the outside casting of the carb, past a small ball bearing then up and out of the brass tube positioned above the main throttle appeture. If this isn't squirting then you will get the problem you describe.

The ball bearing should be free to move in its small chamber, and is prevented from coming out by a small pin. Take bearing out and give that side of the casting a good clean, put diaphragm back in place and reassemble. Don't loose the pin or the ball bearing!!

I had similar problem and this was a happy and cheap cure
 
Thanks for all of your advice. In the end I decided to strip and rebuild the carb with a refurb kit which seems to have solved most of the problem. This brings me on to the oil bath filter though, I'll start another thread for that...
 

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