Volkswagen: 1970 Bus Engine stalls, spark plug wires, engine stalls

Question
I have a 1970 Bus with a 1600cc engine. This engine stalls on me when I start it up. It starts up and then stalls . When it gets warms up it doesn't stall as much. But then after I drive it, for example to work. I try to start it right after I turn it off and it won't start anymore. I put a new carburator on it. I did a tuneup to it. I adjusted the valves, new spark plugs, new 009 distributor, new spark plug wires. The shop that did the work for me said that I needed to put '93 octane fuel in it and drive it for at least a couple hundred miles to let it "blow out". I did as they told me I drove it a total of 500 miles but it still is the same. Now they tell me that I need a new gas tank because it might be that the gas tank is dirty, and that my new carburator is no good anymore and I need to bring the car back in for a whole fuel system flush and the carb has to be taken apart and cleaned. I don't know what it is ? Any suggestions would be great! Thank you .

Answer
Jae,
 Let's assume you do have a rusty gas tank, which is quite possible for the age of the vehicle.  The worse that should happen at this point is the fuel filter gets clogged, or there is rust blocking the tank pickup or lodged in the fuel lines.  There should not be a problem in the "new" carb.  If you find debris in the fuel filter, first try replacing it and see if your symptoms improve.  If so, you have found the reason but not solved the problem because you may quickly get the new one clogged with rust again in short order.  Here is a link on fuel tank restoration:

http://www.ratwell.com/technical/FuelTankRestoration.html

I would add one thing that has worked well for me to knock the rust off the inside walls of the tank.  Get a box of 3/8" nuts, say 25 count.  Lace them together with some strong cord and tie it so you have sort of a "nut necklace".  While washing the tank out with water (BEFORE the acid wash), drop the string into the tank and shake it around in every possible position.  Of course this will help physically knock the larger pieces of rust off the inside walls.  Having the nuts tied together helps to easily remove them when you are finished.

When you are done restoring the tank, be sure to run carb cleaner through the fuel lines and blow them out with compressed air.

Here is one possible restoration kit:
http://www.por15.com/prodinfo.asp?number=S7Q&dept=12

If rust in the tank is not the issue, then the carb is suspect, perhaps it is misadjusted or not jetted properly for the engine size.

Rick