So, last June I posted about my 76 PK losing power and you guys gave me some great advice and I got her running pretty well by the end of the mowing season and she did well over the winter. HOWEVER, we are back in mowing season again and I am having issues again.
She starts running rough, sputtering and losing power when the fuel tank gets down about 2 inches from full. I can limp it back to the fuel can and fill it up and she runs fine. I make a few laps around the pasture and the same thing. I don't cut it off, so I don't think it is heat, It is pretty amazing, as I fill the tank it smoothes right out.
2 thoughts as I write this. 1) Fuel pump (which I rebult last year) is out/weak and the fuel is gravity feeding until it hits carb level but I think the tank sits higher than that. I will look at that in the morning 2) The flow through hole in the bottom of the side baffel in the fuel tank is clogged and fuel isn't flowing well once it drops below the top hole. I cleaned the tank last year, but there is no way to see inside that area.
This is the same thing that plagued me all last summer. Since I was constantly working on it, I never filled the tank because I got tired of draining it. I have: Replaced the fuel cap, replaced the fuel lines, cleaned the tank and filter, wrapped the fuel lines in aluminum foil to keep from vapor locking, rebuilt the fuel pump, rebuilt the carb, cleaned the cooling fins, adjusted the valves, replaced the head gasket and cleaned the piston, replaced the spark plug and ignition wire, and adjusted the carb many times.
When the tank is full she runs like a scalded dog. Any ideas?