Modern Vespa

Do you pre-mix your first tank of gas after a fresh engine rebuild? Engine is auto-lube, if so what is pre-mix ratio and what are the pros and cons of pre-mixing... Cheers!

When I rebuilt my 1980 P200e with autolube I premixed the first tank. The thing smoked so bad I thought the neighbors would complain. Ended up draining the tank and putting in fresh gas. I also drained the 2 cycle oil and started using Bel Ray synthetic. It onlY smokes now when I start it. I have probably 800 miles since rebuild. When I rebuilt my 1979 125 with a 177 Polini kit I just used the autolube and made sure I had oil up to the pump. Never had an issue with lack of lubrication. My thought is if you are going to premix use minimum amount of fuel mix to make sure autolube is working.

one gal of 2% premix will assure there is no gap in lubrication.

You can introduce an air bubble into the oil line to validate it is working. as soon as the bubble is gone you can top up the tank so now it's less than 1% in the premix.

I don't but I do make sure that the oil line is full before I connect it.

+1

I did a 1/2 gallon of 2% premix and run on reserve, and when the bubble gets sucked in (fairly quickly), I filled the tank with clear...

Seen your post on FB. Make sure you have an autolube carb. I bought one last year from Piaggio (sold as an autolube carb with the correct part code) and although it was drilled from the bottom it didn't have the vertical drilling done to it. My supplier took it back and told me it wasn't the first one assembled and packaged wrong...

Check down the carb's throat for the oil weeping hole...

SaFis:
It does, that's not an easy picture to take.. lol

Another thing that I have done for rebuilds is pulling the plug, turning the auto lube to max and spinning the engine over with a drill. All while looking inside the carb for the oil to start coming out.

I rebuilt a 150HP Yamaha 2-stroke that I hooked a drill up to the autolube pump and made sure every cylinder was getting oil. That was a big V6 2-stroke rebuild that really needed the oil. I also left it on max for the first few minutes of idling. NOT an engine you want to mess up after a rebuild.

Great tip Keaton!!!

Can you please put that up here as well? Random tricks, share your best little tips & shortcuts Cheers!

Good ol' freak moped has a video for every topic!

https://www.youtube.com/watch?v=Hku0zfam1A8

I replaced the fuel and oil lines on my US 2005 PX150. I had a difficult time attaching the oil line on the carb connector and when I was finished the oil bubble was longer than I wanted. It was nearly 3 inches long and I thought if I run the engine until the air bubble was sucked in I may get some engine wear or damage. My fuel level was low as the reserve light was on so I added 2 oz of Motul 710 2T oil to the fuel tank. I started the engine and let it idle as the air bubble was sucked in. It took about 6 minutes and the video reference below shows the later part of the air bubble being sucked in. You can see how slowly in travels. Once the air bubble was gone, I rode it for a few miles then added regular 90 octane ethanol-free gasoline to the tank. All is well.