IH carb rebuilds

metalmender11 · May 20, 2011

what is the secret to rebuilding these old IH carbs, I put in complete kits with needle valves etc. new floats but on occasion my H and my cub when you shut them off the gas will overflow the carb , tap it with a screwdriver and it stops what am i doing wrong

GordoSD · May 20, 2011

Your needles are not seating in the seats. The newer vitron tipped neddles were supposed to cure this but I think they made it worse.
Drop the bottom of the carba nd use some brake cleaner and air on the seat. Double check the float pins and holders for good alighnment, and tight so pins can't work out.
And ALWAYS shut the fuel off at sediment bowl when done with the tractor.

rhtx55 · May 20, 2011

The float pivots on pins, check the side to side play, I 'll bet it's a bit loose causing the needle valve to sometimes stick, or you have some trash ( rust debris etc.) coming from the tank and getting between the needle & seat causing it to stick.
Make sure the sediment bowl is equipped with a screen at the top, and where the fuel line goes into the carb, there is a cone-shaped screen there also, these two together should keep most of the harmful stuff out of the needle & seat, if both are present and not dirty, it is probably the float pivot pin.
Some carb kits come with a rubber tipped needle valve, they are notorious for sticking, use a carb kit that contains an all metal needle valve & matching brass seat, they last much longer, won't stick, and are much more resistant to any rust or debris coming from the tank.

504 · May 20, 2011

As said before use a metal needle. the sticking is probably caused by the three side of the needle being too big. Polish the points with a small file or emery cloth.(made in china just needs a little help)

SouthernFarmall · May 20, 2011

If your float tang is bent, it can cause the needle to not be pushed up into the seat. If the tang is bent the other way, then the needle will be continually seated, and you will have no fuel. At least look at your float and make sure the tang is bent correctly. Also, if you replaced the needle and not the seat, there could be problems. Sometimes there are subtle differences between seats, and a brand new needle may not work right with an old seat.
Good luck, SF

Ellis Kinney · May 21, 2011

I had a problem similar to yours on my M. The brass pin that the float hinged on was a little too short and would slip out ot the retaining nothces causing the float to be in the bowl crooked. I used a 1/8 brazing rod which is the same diameter and just cut it slightly longer and solved the problem. This may not be your problem, but if it is the fix is simple. Your idea about tapping on the bowl is something I always do if the tractor hasn't been run in a while.

IH carb rebuilds

metalmender11

Member

GordoSD

Well-known Member

rhtx55

Member

504

Well-known Member

SouthernFarmall

Member

Ellis Kinney

Well-known Member

Similar threads