I picked up this '64 Vespa 90 in non-running condition, and have been able to start working on it over the last few weeks. When I first checked it out after buying it, it didn't have ignition. That was resolved by installing a new condenser and the results were a nice strong spark.
After getting spark I found that it was not getting any fuel. The tank pretty much had corn flake size rust chunks in it, so that put the project on hold until I finished moving into my new home and had time to dig into it. Once settled into my new place I pulled the tank and tried a trick suggested by Len Smith, naval jelly and a box of drywall screws. Shaken, not stirred. After about 10-15 minutes of jumping up and down with the tank, it looked good, but just not ready for fuel. So after some research on the net, I tried something called 'reverse electro-plating'. This worked out great, low effort and great results. To do this, the tank was placed into a bucket of water mixed with baking soda. Attached to the tank was the negative side of my car battery charger and a steel rod is also placed into the bucket while connected to the positive side of the charger. The steel rod can't touch the tank while doing this. When the charger is turned on, the rust is basically pulled off of the tank to the steel rod with a positive charge. I did this over several days, changing the water every 24 hours, brushing paint off the tank, and rinsing the rust out as well. This was also done with a rod that I suspended in the tank to help pull it from the inside as well as the outside. When I stopped seeing noticeable results after about 4 days of this, I stopped and did one more treatment with the naval jelly. This time I used about a ½ a carton of BB's with the jelly and the results were great after about 20 minutes swirling the BB's around in the tank! Next I finished sanding off the last bit of paint on the tank and primed it with some ruby red primer. After priming and putting the gas cap back together, I installed the fuel tap and poured in 2 cups of pre-mix oil into the tank to coat the insides to protect from rust forming until I could get around to starting up the scooter.
In between all the de-rusting activity it was time for a trip down to Motorsport Scooters for a fuel tap, tap wrench, and a carb rebuild kit. I soaked the carb over night in carb cleaner and then installed the new gaskets and needle. Once that was done the carb went back into the scoot to wait for fuel!
Today I installed the fuel tank, made my fuel line connections, turned on the gas for a couple minutes and gave it a few kicks. Nothing happened at first, so I pulled the plug and noticed I still had the original plug that came with the scooter when I bought it. I installed my fresh plug and it started on the first kick! I ran it for a few minutes to see how it would run and it did pretty good, so I grabbed my gear for a few laps around my neighborhood. Tried the brakes out in the driveway first and then went out for my laps. Headlight worked, but need brake and tail light. No horn and shifting is a bit rough, but a complete cable change is in the near future.
I have a few photos of some of the work done to the tank and will also put a link to some more pics on Flickr, as a well as videos on Youtube. Didn't take as many photos as I should have, but you can still we what was going on.
Blab la blab la, more updates as time goes on.
⚠️ Last edited by grscum on UTC; edited 2 times