ORIGINAL: av8tor1977
I could make this a long story, but I won't. Suffice to say that I am fixing a big load of yard equipment to sell, and grabbing some good engines for myself, and today I learned something. Spray carburetor cleaner will damage the one way valves in the primer pump on Zama carburetors, and make them unuseable. It must melt some tiny plastic piece inside the valve or something, but after being blown out with carb cleaner, within seconds the valve will no longer flow. No way to fix it either.
I was using ''Gumout'' carb spray, but I bet most carb cleaner sprays that work well would cause the same problem.
Just thought I would share the ''find'', and maybe save someone some grief!!
Ok, I'll admit it; I ruined several primer pump assemblies before I figured out what was going on...
AV8TOR
I have had the same problem. I threw the ruined primers into my carb junk box. Weeks later I was searching for a primer that I hadnt toasted, and discovered they were all useable, Apparently the check valve in the primer was only temporailly swollen. I now avoid the carb cleaner/ primer connection. There is also a carb with a checkvalve in the high speed jet(cant remember if Walbro or Zama), Carb cleaner will also swell it until it pops out. this definately ruins the carb, as fuel basically flows constanly.