if you are a lucky kind of guy you can try and remove the manifolds and spray carb cleaner in the exhaust ports and with a soft hammer try and tap the top of the valve to move the valve down and spray while doing this and it might free up, its just varnished up from old gas,...maybe you dont have to take it apart, hope this helps.

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1936 1.5 wrecker,1937 gmc coe,1939 Chevrolet coe,1942 4x4 coe, 1942 coe,1946 dump,1947 2 ton dump,another 1947 2 ton dump,1950 coe,1967 c30,1937 cat 22,1936 Chevrolet 5 window foremans coupe, 1914 ford speedster.