Farmall 706 engine freshen up??? Head, rings, bearings

I was in need of a 706 gas engine and found one earlier in the week. Engine (263) will be coming out of a very original 1963 706. Looks like it had been taken care of. Cylinder head has been off at sometime as the head had been cleaned and not repainted. This engine starts well, idles well (possible miss), sounds pretty decent under load in high 4th on the road - especially when speeding up. When in road gear and it reaches rated rpm it sort of sounds like it the engine starts to "float" and possibly miss. It looses its strong exhaust sound. The engine never smokes and blow-by is normal in my mind. I sort of think it has an exhaust valve going out as this is very common with these engines. Generally when the valves start to get burnt up it means the engine is burning some oil. Probably needs the valve lash adjusted as well. My question is if I can't get it to sound right with a tuneup and end up pulling the head and checking/grinding the valves can I just do the bearings and then do the rings to stop oil consumption using the existing sleeves and pistons????? Tractor will not see a plow or disk. Maybe an auger or chore tractor. Years ago Farmall H's and M's were just re-rung all of the time. Can I get by with a ring job once if I find the pistons are not all scored up??? I know ideally that sleeves/pistons are best, but the tractor is just going to putz around. Don't beat me up. Just want to know if I can re-ring successfully. Thanks.

Yes, you can get by with replacing the rings only. Not uncommon at all, especially on a gas engine, even more so if it's hard work days are past.

As long as the cylinder walls are not scored, just hit them with a glaze breaker hone, go back with soft rings (iron, not chrome if available). But one thing commonly overlooked is the condition of the piston ring lands. If they are beyond tolerance chances are the rings will not seat or be short lived. Also check the skirt to bore clearance, and the wrist pin bushings. Looseness of either will cause annoying knocking, but will probably still run a long time.

Now, here's the decision you need to make...

Do you go ahead and install it as is? From the description it sounds like a good engine. If it idles well, that is a good indication the compression is good. You may want to go ahead and check the valve clearance, run a compression test while it is still running. Since there is no blow-by or smoke, that is a good indication the rings are good.

Or, do you go ahead and tear into it while it is out? That way, if you find more serious problems, like the crank needing to come out, rear main seal replaced, etc., then everything is accessible. Also no laying under it with oil dripping in your face!

The sound you are hearing, (if the compression is good, no broken valve springs, sticking valves from sitting) it is probably just needing some TLC, tuning, checking the distributor for wear, timing, carb cleaned, etc.

when they run good they run vary good . And if you want it to run good and stay that way and NOT have issues with the exhaust valves then you only run 30 weight LOW ASH OIL . Before you even think about adjusting the valves take a good long look at the rocker arms for the ware pattern as they always ware off to one side of the rocker arm . Now you can have them refaced by a automotive machine shop if and when you are doing the head or you can just watch how you insert the feeler gauge and keep the feeler gauge only on the worn part to get a good valve set . When setting the valves you do not have to run the engine till hot as long as the temp of everything is above 70-75 degrees . Ing timing is vary important with these engines and on a early 263 in a 706 it is set at 23 degrees at rated high ideal . If you get the idea of putting new sleeves in these engines then you need to see what bore class each hole is as one size does not fit all. On the deck of the block at each hole there is two letters stamped , there will be either a A-B or a C-D . A-B is what comes in the off the shelf kits and will fit but will be to loose in a C -D class bore .

I really hope that you get some good advice on your questions. I am certain that if your topic here was about washing machines, world peace, mice, girls bike shorts, etc. you would probably get more replies than something tractor-related like this. LOL

I will have to disagree about using "soft" rings.
While a soft ring will always seat faster than a harder ring, it will also wear out in a much shorter time. Chances are that your original rings were a combination of chrome and cast iron. Most times, the top compression ring is chrome and the second ring is iron followed by an oil control set in the bottom groove.

All things considered, how much would be saved by not just going with a full set of sleeves, pistons, and rings? If you are only tripping over $50 or $100, you might want to rethink the whole thing. You just never know what you might find when you take out the old pistons. Ring lands might be bad, bores could be scored, sleeves could be worn out, piston skirts collapsed, or wrist pin problems. All of this would be taken care of by putting a kit into it. Then you would have an engine in really top condition.

Not long before he passed on my uncle told me how he had the engine of his Ford 860 rebuilt three times in the fifteen years that it was the main horse on the farm. I was later told that to him re-ringing was a rebuild. I think that despite your plan to use it only lightly, that you should base you plan on what you find once you evaluate it.