What a combo of symptoms. The need for a lengthy crank cold is indicative of lack of fuel in most cases. The hard start warm, and need to set at idle speed, indicates that it may also be lacking fuel as a wide open throttle plate will try to pull fuel ... that may not be there, so it won't even fire, as the mix is too lean.
I would check for a good flow from the tank by removing the fuel line from the carb, and catching the flow in a proper container. You should get full-tube flow of gas if it is gravity fed. No restrictions. If you have a clean fuel line, filter, and you get a slow feed, you might have a too-restrictive fuel filter. I have read that pumped system filters are more restrictive than gravity fed, but don't bet your paycheck.
Any way, you should get a full-diameter flow in either case. If you get that, then pull the float bowl and check that the float will drop properly, and there is not crud in the float valve.
One other thing is that an engine with valves adjusted too close may be difficult to start hot. The clearances close up, and may not allow good valve seating. If you ask around here, you can get instructions on valve adjustment. I think Walter has them available via email. Crankshaft to be at 1/4" past TDC to adjust OHV engine valves, from readings.
Does the installed carburetor have an adjustable 'main jet', or is it fixed? Most are fixed anymore. The idle mix is still adjustable on a lot. The idle mix is used as a 'transition' mix for the engine to accelerate to operating rpm without misfire, FWIW. If too lean, you will likely get stumble and hesitation as you advance the throttle to operating speed.
tom
I would check for a good flow from the tank by removing the fuel line from the carb, and catching the flow in a proper container. You should get full-tube flow of gas if it is gravity fed. No restrictions. If you have a clean fuel line, filter, and you get a slow feed, you might have a too-restrictive fuel filter. I have read that pumped system filters are more restrictive than gravity fed, but don't bet your paycheck.
Any way, you should get a full-diameter flow in either case. If you get that, then pull the float bowl and check that the float will drop properly, and there is not crud in the float valve.
One other thing is that an engine with valves adjusted too close may be difficult to start hot. The clearances close up, and may not allow good valve seating. If you ask around here, you can get instructions on valve adjustment. I think Walter has them available via email. Crankshaft to be at 1/4" past TDC to adjust OHV engine valves, from readings.
Does the installed carburetor have an adjustable 'main jet', or is it fixed? Most are fixed anymore. The idle mix is still adjustable on a lot. The idle mix is used as a 'transition' mix for the engine to accelerate to operating rpm without misfire, FWIW. If too lean, you will likely get stumble and hesitation as you advance the throttle to operating speed.
tom
