hi all on cleaning carbs on genesis 1200. on blowing through oil connections on carbs found, what i though were blocked.but are pressure release valves. were the oil pipe pushes onto carb between there and relivent opening in carb jet block opening. tested by pushing small pipe on carb jet block. pushed carb/ choke cleaner can small tube with a bit of tape round it for tite fit on other end of pipe. pressed, cleaner splutterd out from hole inside jet block. when pulled out pipe this was still pressurized. wondered if these valves wore with age. or block. no oil will mix in carb and seize piston ? could cause mag, center, pto engine trouble. keihin carbs. no access to valves sealed in pipe opening and jet block.

old or worn oil pump, pressure weak, valve will not open strave of oil, expansion of old oil pipes will reduce pressure and length of pipe IE: pto oil pipe?

i think will convert to pre mix to eliminate possible problems, read many time on this forum, after peoples run in engines with premix first couple of tanks. then the engine seizing, rings braking up pistons. oil starvation? no mention of valve in manuals or forums as i can see. valve fitted in all three carbs looks like it stops petrol returning down oil pipes