Carburetor Problems

[ScottyG]

Well, I purchased an IH rebuild kit for my original IH carburetor, primarily for the gasket but decided to go hog wild and use all of the parts included. IMHO, the kit is garbage. The fuel valve needle gets stuck in the brass ferrule when the float closes and you literally have to tap the carb to get it to unseat. The directions are for an H or an M not a Cub. Very poor design but you probably all knew that already.

Anyway, as the old adage goes, don't fix it if it ain't broke. That said, I'm now having carb problems left and right. It's stumbling terribly so bad that I'm having loss of power, poor idle, etc. I put back all of the old parts into the carb and blew out all of the fuel jets and cleaned the internal strainer. I then followed Lurker Carl's float height setting using a standard caliper to set at 1 13/32" with the float closed and 1 19/32" with float open (hanging down). Other than that, what else can I do here? After setting the float, I at least have my power back but the carb is still stumbling and... I've never had that problem before.

Finally, what is the typical idle screw setting from stop?

Any advice would be greatly appreciated.

[Jack Donovan]

Most of the guy's have been putting in the IH cub cudet Koller needal and seet ,it has the teflon tip. I my self still have the oridgenal, when it gets a little sticky I use a dab of valve lapping compound , rotate it a few times, clean it up and walla"

[Don McCombs]

Scotty,

Did you get the carb kit from a Case/IH dealer?

[ScottyG]

Well after reading a bit further and rechecking my packaging, this is not an official IH kit. Sorry for the confusion folks. Its a TSC which is apparently some pretty rotten junk. Oh well. At least the gasket holds that much I know since I don't need to choke her down to keep her running. Just wish I knew what was causing the stumbling.

I can also look at the Kohler needle but since the carb ran ok before I monkeyed with it, I'm at a loss at the moment.

[Bigdog]

That makes more sense. The IH kit is a good one!

[Donny M]

I agree with Bigdog

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

Scotty, there should have been a little spring in the kit that hooks over the lip on the bottom of the valve and under the float, so the weight of the float pulls the valve down.

[ScottyG]

Well that makes sense. I didn't see a spring in the kit and come to think of it, I don't remember putting one back in the original ferrule either. Let me check the tool shed and I'll get back to everyone.

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

The spring looks like 2 verytiny hoseshoes hooked together at one end.

[ScottyG]

Nope, I don't see a spring included in my remaining kit parts (which is most of them since I put all the old parts back into the carb).

Did the original fuel valve have a spring too? I wouldn't think so since it seems to glide pretty evenly under gravity.

[Buzzard Wing]

Scott, Lurker Carl WARNED about using a non-IH kit. I had the spare float valve because I followed his instructions on getting the Kohler (viton tip?) kit. I sold the IH one on ebay, so all I have is the old one out of the carb. Still haven't fired it up yet. You should be able to get the Kohler kit at Baker?? The IH kit is about $55.
Looks Like the float was stuck on the new one, but seems to have cleared up. (acted up just so it wasn't running at the auction??) I will likely put the IH kit to that one too.

[Lurker Carl]

In the IH carburetor, there is no spring connecting the needle to the float. You don't need it when you use genuine IH parts or the genuine Kohler needle and cage.

[ScottyG]

Well, I completely read through your self help fixes, Carl. They're top notch by the way!

It looks as though the top of my carb casting was a little warped and I've done what I could to shape it back. It's not perfectly flat but I believe that the gasket is making a good seal.

I also noticed a small, hairline crack around the carb throat. Right at the base of the circular protrusion that comes out of the top of the casting. This is completely internal however (I doesn't go through the casting) so I don't think that this is my problem. I readjusted the float setting again, this time without the gasket in place. That seemed to control some of the stumbling but did not completely cure the problem. Occasionally if I'm mowing, the tractor wants to die and if I apply 1/4 choke, it will pick right up. This suggests a vacuum leak correct? This thing is really frustrating the heck out of me. Pricing new carbs seems out of the question to me since the thing worked before I monkeyed with it. And... it's just two jets, a fuel valve and some gaskets. What could possibly be wrong ??:lol:

At this point, I'm starting to think the cause is due to other things. Perhaps, I bent the governor rod slightly when I removed the carb? Could this cause some slight stumbling if not adjusted correctly? It's not a surge but a tumble. Kind of like the loping on a Harley

I guess the last symptom I've got is that when I'm at idle, I used to be able to cruise in low gear without a problem (when parking, pulling into the shed, etc.). Now, if i don't feather the clutch, the engine dies.

[George Willer]

In the IH carburetor, there is no spring connecting the needle to the float. You don't need it when you use genuine IH parts or the genuine Kohler needle and cage.

I've had a littlle trouble with the Kohler needles sticking, so I went back to the originals. I put the needle in the cage and tap it lightly so the cage conforms to the needle better and have no more problems. I rarely shut the fuel supply off on any of me tractors and don't have any leaking problems. I'm careful to address the other places where they can leak when I have them apart. I never use the spring.

[ScottyG]

Well, I refuse to let this thing beat me so I'm absorbing all of your advice. It's burning me out though and I'll usually let a day or to go by before I try to tackle it again