48 cub carberator

[G Dorn]

I been trying to get my 48 cub from backfiring fo a month now.I think my carberator may be the problem.I purchasev3 carberators but none have the right size air intake bore mine is 1 1/2 id.I can not find a carberator that replaces the original
What part # do need for my 1948 cub? My engine # is 251341 tractor serial # is 23735.Any help would be appreciated

 

[grandpa Love]

I been trying to get my 48 cub from backfiring fo a month now.I think my carberator may be the problem.I purchasev3 carberators but none have the right size air intake bore mine is 1 1/2 id.I can not find a carberator that replaces the original
What part # do need for my 1948 cub? My engine # is 251341 tractor serial # is 23735.Any help would be appreciated

More than likely the carburetor intake is correct and your hose connecting it to the pipe is wrong. The later cubs (from the '70s ) used a zenith carb ,it has a larger intake. Yours should use an IH carb. Or this kipa replacement from Amazon. The backfiring sounds like a timing issue to me . Posting a couple pictures of the carb and tractor would help us troubleshoot.

 

[grandpa Love]

My video shows timing an H4 magneto but the process is exactly the same for your Cub's J4 magneto.