Farmall Cub

Fellas, what's the prognosis for fixing a smoking engine (Super A.)

I plan to work it through the summer and then take it apart and try to fix it myself as much as I can...

Is it possible to just install new rings and valve guides myself and button it back up? Or could it be smoking for some other reason?

It won't get a heck of a lot of use, either way, I tend to use the Cub a lot more.

Allen - the feasability of just replacing rings is slight. If you have smoking, that is indication of significant wear. The cylinder walls are most certainly worn to an oval or egg shaped configuration and the amount of wear is no doubt too great to allow for good fit of over-size rings only. The cylinder walls will need to be bored to a uniform size and either over-size rings or pistons and rings will need to be used. Also, most likely, there will be bearing wear as well. Either way, I don't think rings alone will solve your problem.

So everything has to be machined back to round, instead of just putting in oversize sleeves and undersize bearings.

I would first take the head off. Take some measurements and go from there. The first thing to look at is the ridge thickness at the top of the cylinder, which is the first indication of the amount of wear. If the tractor hadn't been used for a while, the rings may be stuck and you could let it soak in Country Elliot's Kroil. Depending on the color of the smoke it could be a fuel/air mixture problem. Or it could be valve seals. Check it out in a methodical manner. Do the compression test with and without oil in the cylinder. One of these days I'm going to practice what I preach! Larry

Me too Larry. My Super A smokes like I do and the front seal has been leaking for 30+ years. It's had two sets of rings and bearings since new and neither time helped it at all. Never touched the sleeves or head, had 2 oil changes since new. I would do all that now, but when I die my son is going to either tear it up more or let it rot down. It runs as if it were still new, so I'm not going to do a thing to it but maybe fog mosquitoes.

The super A has wet sleeves as I recall, and if the cylinders are bad out of round or worn, you cna repalce the sleeves and pistons yoursel rather than needing a machine shop to bore it.

Hi Allen

Are you getting a lot of blow by out the crankcase vent If not I would look to the valve guides. The SA being overhead valves the valve seals get old and hard or break off at least in car engines.

Just a thought Billy

I do get what I consider to be excessive blowby out of the oil breather, but I don't know what I'm talking about - I just know that sometimes the oil seems to be flying out the oil cap as hard as it is flying out of the muffler

I was hoping I could buy one of those "tune up" kits on eBay for $300 and put in the new sleeves myself, along with the new domes pistons and rings...

allen, that sounds like sticking rings. Have you tried putting some SeaFoam in the oil and gas and working it for a while. Not just idling, but actually working it.

Allen,

If you think the SA has power now try this if you rebuild it.
An SC engine rebuild kit will fit the A block making a SC out of an SA
This will allow you to do things in 3RD gear that you you could only do in 2nd before.
I know this for a fact as my brother & I did this to his SA in the 70's.

Can you picture your SA running a 9' cut New Holland hay bind
or how about a John deer 14T bailer.

John, what does sticking rings mean?

The tractor did sit for a very, very long time without being run. I put SeaFoam in the oil immediately and ran it for a while, mostly idling, for several hours, then changed out the oil and put fresh in just yesterday. I didn't dare add more SeaFoam for fear it would thin the oil and make it smoke more.

I have SeaFoam in the gas for sure. (Based on your recommendation.) Thankfully NAPA carries it here now, as well as PB B'laster by the gallon!

Allen With that much blow by I would say stuck rings too. A "stuck" ring is one (or many) that is stuck into the ring lands on the piston which keeps it from expanding and making a seal on the cylindrer walls. I would take out the plugs put koil in the cylinders for a week and turn it over once a day adding koil as needed.

I run seafoam in the oil of my ranger with + 200,000 miles on it for some reason if I add 2 ounces every 1,000 miles it keeps it from spark knocking. I have been doing that for the last 20,000 miles so I do not think adding it to your oil would thin it out any and it will help.

Billy

Aha! Gotcha. I don't have any KROIL, but I will take out the plugs tonight if I get a chance and put in a couple teaspoons of SeaFoam.

Oh, and yes, the tractor sat for a long time without being run, so stuck rings is a possibility! I sure hope that's it

Allen you may wat to use PB blaster or breakaway I do nto think it would hurt to mix it with the seafoam.

Billy

I just put new oil into it, would the PB B'laster leak down into the crankcase and screw up all that nice fresh new oil?