Thread: Small block 400 2200 rpm misfires! Help please!!!

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My boat has a small block 400 it's got 202 heads,flat top pistons and a big cam! The boat ran awesome for two years then it sat for 2 summers! At about 2200 rpm it cuts out and runs real rough!
I have changed out the fuel,fuel pump,fuel filters, carburetor, distributor cap and rotor, new points, spark plugs and wires, installed a new coil, checked the compression 119 down one side and 116 on the other!! I'm lost I've pretty much exhausted my funds and I don't know what else to do! Any advise or help would be greatly appreciated!!

Just wondering did you foam the engine when put away??? May have rusty valve seats or valves. Could be timing???

Yeah put that seafoam stuff and stabil!! I've checked timing and points at leased 10 times! Is there away of checking the distributor?

Change the condensor

did you set the points with a dwell meter???

i worked on alot of boats. in the summer i did six tune ups and oil changes a day long with alot of other fun stuff .stern drives rebuilds .engine rebuild . rigging work. FUN FUN Fun . two of the last things we ever replaced were fuel pumps and coils. the first thing was point s condensor .plugs . if this stuff looked good then unhook the tack most boats have lower dollar gauges when tacks fail they can make engine miss . water sep/ fuel filter . anti siphoned valve . after this do a compression test .alot of the old YL mallory s the top part of the dist would wear out and the dwell would not set. like jerry said you did check the dwell plug gap should be .035