starting issue

[lo-bob]

My '57 Low boy will start in most cases within a couple of revolutions but only if the throttle is all the way down. if the throttle is advanced much at all it will not fire or start. If I advance the throttle after starting it will stall out unless I feather the choke. When running at a fast idle it will significantly surge. Cranking speed is good and timing, plugs, valve lash, compression and carb have all been checked to specifications in the manual. I have good power when warmed up although if the throttle is advanced quickly it stumbles a bit.
Any suggestions?

[RaymondDurban]

All your symptoms lead me to suspect a fuel restriction. Pull and clean the main jet on the side of the carburetor. Check fuel flow through the carb after you pull the jet, should be a steady stream out the hole.

[Eugene]

If Raymond's suggestions don't solve the problem, check the fuel level in the carburetor bowl. Check the gasket between the carburetor and manifold. Check the carburetor top for warpage and condition of gasket between carburetor top and bowl.

Edit. Check to see if the gasket between the carburetor top and bowl is correctly installed. On some carburetors the gasket can be installed up side down.