8n bogging

[HoraceTOK]

When I drive my ford 8n, it bogs down then goes back to normal bogs down and goes back to normal ex. Please help

 

[Larry NCKS]

1st thing I'd check is fuel on that one. Is it getting to the carb in sufficient quantity? If so, is it getting through the carb?

Also (and some prefer to do this one first) does it have good fat blue spark at the plugs that'll jump at least a ¼" gap? Are the plugs good and a brand other than Champion? (Don't ask me why, but Ford engines do not generally like Champion plugs.)
How's the timing, both static and advance?

(You might tell us whether this is a front distributor or side distributor as well.)

Is the air filter sump and screen clean?

Does it have any vacuum leaks between the carb and engine block? Spray manifold and carb connections with a combustible aerosol (be extremely careful if the engine is at operating temperature) A wiff of something like this at a vacuum leak will make the engine perk up a bit momentarily.

Is compression good?

 

[Larry NCKS]

Oops! You might also check on the N board. Those fellas are dedicated to N series tractors over there.