85 hp force backfire

[fordworker]

fighting this since last summer. now trying again. 1987 model. was running great and someone put water in fuel tank. drained and flushed w fresh fuel. new fuel line and installed inline filter. serviced carbs. new plugs. strong spark. 125 psi all three cylinders. checked flywheel key. it has ran off and on but never correctly. misses and backfires intermentently when try to accelerate. idles smooth most of time. screws set at 1 1/4 out. clean fuel sample. strong exhaust backfire not thru carbs. have not changed any cable or linkage adjustments. suggestions appreciated. thinking of parting it out very frustrated with it.

 

[shadow7g]

Re: 85 hp force backfire

Get a timing light and check the timing. Pull the plugs out, ground them then check the timing. You could do it with the engine running but personally thats not how i did mine just because of the potential hazard. What did you do to the carbs? When you replaced the plugs did you cross any of the wires? Top to bottom should be 1,2,3 (i own a 1984 85 HP so yours COULD be different).