My Cub's recent woes

Mon Oct 29, 2012 1:44 pm

Howdy again folks. I've been away from the forum for a while, but my cub and I have been working regularly. It has slowly been loosing power and running richer as time goes on. Last weekend I put the plow on it and went to plow the gardens up for winter, but the ol' gal wasn't up to the task. I would sink the plow in and it would stall out after about 15 feet. It just doesn't have enough power to pull the plow anymore.

It has always run rich, even after rebuilding the carburetor. But now, it runs so rich it can hardly even pull itself. It has the IH carburetor which I rebuilt a couple years ago, but the bottom of the bowl had flaked and I suspect the bottom jet can't seat properly. Since there's no real adjustment to regulate the fuel ratio, could you fine folks help me figure out what I need to do?

Thanks,
Ben

Re: My Cub's recent woes

Mon Oct 29, 2012 2:06 pm

Ben, When you rebuilt the carb did you put in a new main jet and discharge tube from an aftermarket kit? You may have ended up with the wrong size. Can you read the carb part # on the edge of the flat surface opposite the gas intake?

Bob

Re: My Cub's recent woes

Mon Oct 29, 2012 2:06 pm

Have you checked the governor linkage to make sure it's adjusted properly, Maybe also add a hotter plug and make sure the choke is open all the way. IH carbs have a piece that fits on the choke shaft that the choke rod goes into to make the choke function. These often get stripped out and before you know it the choke isn't fully opening back up when the lever is pushed in. Just a few thing to check. Hope it helps.

Re: My Cub's recent woes

Mon Oct 29, 2012 2:37 pm

Thanks for the tips. I have already checked the choke to make sure it was okay, and it is operating fine. I've never touched the governor.

Now, yes, I did rebuild the carburetor with a TSC kit. And yes, I did replace the parts you mentioned. I am not sure if that number you asked for is still readable, but I will check it the next chance I get. Have I rebuilt it with an inferior kit? When I first got it two years ago, it acted just like it does now. After the carb rebuild, it ran much better until over this past summer when it has slowly gotten worse and worse.

I'm wanting to use it next year for plowing and cultivating. Also, I hope to get my sickle bar mower (which is a basket case at the moment) working and use it as well. The Cub has got to run better than this for be to be able to use it.

Re: My Cub's recent woes

Mon Oct 29, 2012 3:04 pm

I would still check the governor linkage. I would also install a hotter set of plugs. But you could just have a weak ignition system. Maybe the coil has seen better days and is just putting out a weak spark. Also timing can make a big difference. I just got another cub the other week and cleaned carb, new points and coil, new plugs, And it still was down on power. Checked timing and it was off 8 degrees. Got it dialed in and it was running purdy good :D

Re: My Cub's recent woes

Mon Oct 29, 2012 3:26 pm

When were the valves adjusted last?

Re: My Cub's recent woes

Mon Oct 29, 2012 3:47 pm

Well, I've never checked the timing... And never adjusted the valves. I figured this was all a problem with the fuel mixture. I'm sure it wouldn't hurt to check the valves. I should check the timing as well just to be sure its not off.

Re: My Cub's recent woes

Mon Oct 29, 2012 4:49 pm

Ben B wrote:Well, I've never checked the timing... And never adjusted the valves. I figured this was all a problem with the fuel mixture. I'm sure it wouldn't hurt to check the valves. I should check the timing as well just to be sure its not off.
Conduct a 100% engine tune up, include compression tests and valve tappet adjustment, then ignition and finally carburetion.

Re: My Cub's recent woes

Mon Oct 29, 2012 5:51 pm

You know, that is WISE advice! Its definitely overdue for one. Thanks. I will definitely have many questions in the process.

Re: My Cub's recent woes

Mon Oct 29, 2012 5:53 pm

After a recent carb rebuild I had a similar issue. My fix was easy and simply an adjustment of the screw on the front of the carb. Hold a small flashlight and use a small, flat blade screw driver and see if that makes a difference. It may not be your problem but it is an easy fix if it is.

Todd

Re: My Cub's recent woes

Mon Oct 29, 2012 8:44 pm

Ben B wrote:Now, yes, I did rebuild the carburetor with a TSC kit. And yes, I did replace the parts you mentioned. I am not sure if that number you asked for is still readable, but I will check it the next chance I get. Have I rebuilt it with an inferior kit?


Yup and I think the vast majority of our members would agree that the TSC kit is less than acceptable/inferior. A genuine CaseIH kit although expensive is worth every dime. If you need parts that are not in the CaseIH kit then the Steiner kit would be a good choice. Very reasonable price.

Re: My Cub's recent woes

Mon Oct 29, 2012 9:03 pm

this is the kit you need
http://www.ytmag.com/R5097_21824.htm
you will also need this gasket as I do not like the one in the kit :D
http://www.tmtractor.com/new/fl/921fp.htm
Boss

Re: My Cub's recent woes

Tue Oct 30, 2012 7:38 am

Thanks folks for all this advice and help! :D To be honest, when I got the cub 2 years ago, it was a rough running tractor that I easily fixed with a carburetor kit, and by fixing its electrical problems. After that, it ran plenty good enough for me to leave it as it was. That's why I didn't dig any deeper into checking out its troubles.

I will rebuild the carburetor with the correct kit. That kit does have more parts than the one I used, and it does have the seat it needed that WASN'T in the old kit. I will also get the gasket Boss recommended.

Thanks a bunch!

Re: My Cub's recent woes

Wed Oct 31, 2012 5:32 pm

Just a thought, but have you tried running it disconnected from the air breather? When I hear about carbs running increasingly rich I always think of an instance where I had a mud dauber nest in my intake pipe..Any obstruction like that can cause similar symptoms...

Re: My Cub's recent woes

Wed Oct 31, 2012 8:19 pm

Eugene wrote:
Ben B wrote:Well, I've never checked the timing... And never adjusted the valves. I figured this was all a problem with the fuel mixture. I'm sure it wouldn't hurt to check the valves. I should check the timing as well just to be sure its not off.


Conduct a 100% engine tune up, include compression tests and valve tappet adjustment, then ignition and finally carburetion.


:Dito: