Farmall Cub

This weekend, I did a few repairs in my continuing saga to get this cub mechanically in good shape.

1. Since there was a really old rear tire that didn't hold air, I ordered a new one from tucker tire. I've heard good things about them from the board. I decided to get one with a rim on it, because the one on it was pretty well dinged up, and it didn't cost much more. They shipped it quickly, but when it got here it was quite scratched and rusty. I was a little disapointed with that. Then when I went to put it on, the centers would not fit inside the rim. I had to use an angle grinder to remove about 1/4" of metal from each of the 4 areas the center bolts onto. I also had to get new longer bolts with washers, because the bolt holes are empty, unlike the originals that have a place for the bolt head to rest in the middle. Now that it is on and working, I really like it. But I was cussing a little when I found out that what should have been a 15 minute job would take me half the day. Just a heads up for others that may get rims from tucker. Expect alterations.


2. After I got the tire on, and did a little drive test, it was havning trouble with keeping power up. I couldn't even start in 3rd gear, or run the mower without a stall. So I took a look at the governor shaft and saw a good bit of play there, so I did the aluminum foil fix. It took all the play out there. I was able to get her going in 3rd gear now. I could start the mower, but It didn't cut with the deck all the way down. So i looked some more, and noticed that there is a bit of play in the cup part that is hooked to the governor spring. Also the spring seemed like it wasn't holding tight all the time. I will replace the spring. Is there supposed to be any free movement of the little cup that holds the rockshaft? The part that connects to the gov spring. If not, will the spring most likely be the culprit, or are there other common areas that need to be addressed there?


3. OK, last one. I had smoke blowing out of the oil filler tube. I read that this meant that the breather tube was likely cloged. So I took that tube and all the connections off. They were plugged, so I cleaned them in parts cleaner, and the tube as well. then I blew them out, and air was passing freely. I also poked into the holes they screw into, and it was free of obstrucitons. When I replaced the tube, there continued to be smoke blowing out of the oil filler tube. What else could be causing this? I checked the radiator, and there was no bubble, and the radiator level is unchanged. The smoke is slightly whitish, but its hard to tell.


Sorry this is so long, just saved up all my weekend questions. Thanks for any help, guys.


Greg

1, Call Tucker. Someone else had a post with similiar problem, and Tucker corrected it for them.

2. Should not be any play where the shaft goes into the socket. Can be fixed by either making a shim (soda can works good) or by the use of Loctite, Or as on my 48, both fixes are in use.

3. Sounds like time for a compression test.

1. I got the wheel to fit. I'm not gonna send it back or anything, cause I needed the tire now. Its good now, and I'm happy.

2. I already got the shim where the shaft goes in the socket, I need to know if the socket itself has play from the governor.

3. I have a guage, I will dig it out.

thanks.

3. Ok, I went and did the copression test this morning.

110 - 0 - 95- 110


Yep, that is no typo, number 2 is dead. The plug was really gunked up when I took it out, and I started to cringe. Then I did the test, and it wouldn't move the needle at all. What do you all think? I would think it is a hole in the piston, eh? Or stuck valve? bad rings would at least give some compression, right? I'm not sure.

It runs really smooth without a load. Starts really easily. Hmmm, not sure what to do with it.

Time to yank the head IMHO.

The other three cylinders are primo based on my limited knowledge and experience. Depending on how #2 looks, you might be able to cobble it back together with one piston. If the rings are good, I wonder how kosher it would be to just replace the one piston and use the old rings to maintain piston/ring fit. Betcha some old farmer did that somewhere sometime.

Then again, could it be a blown head gasket? The gunk on the plug tells me she's getting oil from down below, though.

It could indeed be a stuck valve so it may not be as bad as you think. You might want to consider pulling the side cover off before you pull the head. It might give you the answer and save pulling the head.

I agree with B.D. on the probability of it being a stuck valve. Or badly burnt valves. My little Metro had 1 completely dead cylinder and it turned out to be 2 very badly burnt valves. Lets hope for the best on yours that they are only "Stuck".

Today, I took the valve cover off, and sure enough, number 4 valve was stuck in the upward position. The tappet moved freely. I took out the number 2 plug and pushed down on the valve. It reluctantly slid down, then I turned the engine and it pushed back up, but didn't come down. So I sprayed some PB blaster on the valve, and moved it up and down like this about 50 times, and it started to move on its own. Hooray!! Much easier than I thought it would be. I put it back together and started the tractor up. I am embarresed that I thought it was smooth before, because now it is firing on all 4, it is 10x as smooth. There was lots of bluish smoke, I am thinking it is just all the gunk burning off the inside of the cylinder. I didn't have time to run it too long, just to warm it up. I'll watch and hopefully it will stop. Then I pulled the plug again to check compression. The plug had cleaned itself up alot. The compression checked at 90. Not too bad, 110-90-95-110. I won't be able to try it out to see if it will mow until saturday, but I'm feeling this will have fixed the underpower problem. Keeping my fingers crossed.

ChickenWing. Also, may be a good idea to add some "Marvel Mystery Oil" gas additive to help with the valves. (2 ozs to 5 gal) Previously heard this on the board and tried it myself............

Either way, 4 cylinders running is a lot better than 3 Good Luck

Well, I got a chance to get out and try to mow today. I'm still having a little problem with it. At first, when I tried to mow, it just bogged down and would move, but would never recover, just kept bogging, even with the mower off the ground. Then I ran the mower without being in gear, and it ran full power, and the governor engaged to bring it up to speed. Then I tried it again, while in gear, and let the clutch out really really really slow, really, and it was able to run and mow quite normally. Then I hit a patch of heavier grass, and it bogged down. When I got past the heavy grass to already cut grass and lifted the mower, it wasn't able to recover until I pressed the clutch. Any ideas whats going on here? It like once it starts to bog, it stays bogged.

This is what I've done so far.

Rebuild and cleaned the carb. Straightened the warpage. Seams to have good gasket seal.

Running out of a clean plastic gas tank till I get the regular one cleaned up.

Took slack out of governor rockarm with aluminum foil shim. I think the spring needs to be replaced, though, cause the whole cup and rockarm moves a little bit together.

The mower blades are pretty sharp, and the spindles move very easily.