Last fall I picked up a Funtana with a YS .63 for a fair price. I was told the engine was only broke in, but when I ran it on my test stand it kept betting air bubbles in the line feeding the carb. I put a gasket set in and replaced the diaphram. it seemed to work on the test stand. I reinstalled it on the Funtana and under load it started to run lean again (air bubbles in the line feeding the carb). I'm at my wits end and asking for help.

Thanks
Dave Simmons