farmall cub problems

[SCcub38]

I have been working on my grandfather's cub with my dad and others for a couple of months. The tractor has run like a champ for well over 50 years without problems. All of a sudden one day (about 4 months ago), after running it for a couple of hours, it died under load. Ever since then, the tractor dies under load. At first, it would do it after an hour or so, when it was hot. Then, progressively it would quit after only a few minutes, without the pto engaged. We replaced the points, condensor, and coil. I cleaned the sediment bowl and fuel line going into the carb. In the video you can hear/see what it is doing.

From what I have read, many think the problem is a carb issue or govenor problem. thoughts?

[CPIII]

Did you try cleaning the main jet...That is what mine does when there is something clogging the hole in the main jet. just run a soft copper wire through it and then blow it out.

[Eugene]

Agree with CPIII. First thought, carburetion or fuel flow problem.

[SCcub38]

Yes. The video is what it sounds like and runs like after I cleaned the main jet with a wire.

[CPIII]

Darn! Well then to me the only thing else other than a fuel problem would be a sticky/slow responding Governor problem. I have very little experience with Cub Governors. So I will have to let someone else take it from here.

[Eugene]

Yes. The video is what it sounds like and runs like after I cleaned the main jet with a wire.

That doesn't preclude a fuel flow or carburation problem.

More trouble shooting required.

[CPIII]

You are right Eugene.....just thought about the fuel level in the carb could be low and the bowl is filling and emptying causing the surging. A quick test would be to start the tractor and then turn of the gas if the engine dies very quickly that may point to a low fuel level in the fuel bowl. I know my cub will run for 20 -30 seconds or more when I turn off the fuel valve.

[John *.?-!.* cub owner]

I agree, it sounds like a fuel problem, but considering what you have done I would look into the ignition. I had one do that exact same thing several years ago, that turned out to be the coil. A burned set of points can also give a similar circumstance.

[Rick Spivey]

Check fuel flow into the carb by removing plug on bottom. You should get a full steady stream not a trickle. I have been fooled on more than one occasion, but this one definitely sounds like fuel issues to me. I would insure proper fuel flow before diving into ignition.

[Jim Becker]

I don't believe anyone has mentioned the screen at the carb inlet. If it fails Rick's test, it is a prime place to check. If it passes, it should be OK.

[Rudi]

There is dirt/crud in the fuel system. Start at the tank and work through it - fuel sediment bowl, as Jim mentioned the screen at the carb inlet, the needle and seat - could just be a flake of varnish - don't ask why I know that - float sticking -- stuff like that. When you take the cage out - hold it up to some natural light - if there is crud or varnish in there it will be pretty obvious - either dark or cloudy.

[Boss Hog]

Question, does it help if you choke it some?

[SCcub38]

I disassembled the carb to see what is going on in there. It was full of dirt that I am in the process of cleaning. Hope this is where all the problems were. Any recommendations for a carb rebuild kit? It is an IH carb. I don't see any numbers on it distinguishing which IH carb.

[SCcub38]

https://m.youtube.com/watch?feature=you ... t7t6zksWUc

That is a link to a video of what the carb looked like after I disassembles

[Bill Hudson]

SC,

You have the IH carb. Steiner has what is considered an excellent carb repair kit. These folks http://www.mcdonaldcarb.com/ also have an excellent repair kit. Avoid, at all costs, a Tisco repair kit -- incomplete and some parts don't fit all that well.

As for the crud in the carb, it came from upstream. Replace the gasline and I install one of these http://www.farmallcub.com/phpBB2/viewtopic.php?f=139&t=38266 and they work wonderfully. After the fuel line you need to clean/refurbish the sediment bowl and gas tank. I'm in the process of cleaning the fuel system in our son's Lo-Boy (dang kid will not listen )right now

Good luck.

Bill