Piston ring help?

Howdy folks I have ordered some new rings for the 8n as well as all new gaskets, water pump, belt, oil filter ect.. I will also be ordering the valve train kit. My main question is how do I take out the pistons to be able to replace the rings? I am brand new to this and never have worked on engines in this depth. I already have the head off as well as the rest of the components off of the engine block. I suspect that I have the separate the block from the oil pan so I can get to the crank shaft and thus the pistons. I was getting some oil blowing by one of the cylinders and I couldnt get the rings to come back around when it was running. Also the valves look like the original 1951-52 valves. They even say Ford on the top still and have a good amount of carbon on a few of them. I can break the tractor in half if I need to. I heard that this would make the engine rebuild way easier and prob make painting a heck of a lot easier as well once its rebuilt. Anyway I know this is long winded but I appreciate your time and help. Thank you in advance.

Also I did a compression test and I was getting 90psi on all four cylinders except for cylinder 2. It was getting 85. I know it should be much higher. This is why Im doing a complete rebuild.

Probably should replace piston and sleeves together

CTX1836,Replacing rings is not a complete rebuild.You need pistons ,selves rings and a good manual,bearings,oil pump rebuild kit,valves,seats replaced or ground,and much more.Ask on the Ford N board for more help.

Do you have a repair manual for your tractor? That is the first thing you should order. The normal operating compression for that tractor, I believe should be 95 when it was new so I really don't think that is your problem. You may have a broken oil ring depending on the amount of oil blow by you have. Did you do a wet and dry compression test on that engine? That will tell you if it's rings or valves. And I guess question #3 would be, do you have the necessary tools to do the rebuild on the tractor? The guys on here will be glad to help you along but Myself, I wouldn't think of rebuilding it without having a manual so I would know how to do it especially the torque values required. So many tractors rebuilds are begun then end up as scrap because the owner doesn't follow the manual and gets in too deep and gets frustrated and gives up on it. Good luck with the rebuild

I would recommend a complete overhaul, sleeves, pistons and rings. You'll also have to check the crankshaft for wear and also the rod and main bearings.

(quoted from post at 03:23:18 07/23/21) Also I did a compression test and I was getting 90psi on all four cylinders except for cylinder 2. It was getting 85. I know it should be much higher. This is why Im doing a complete rebuild.

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What you're doing is called a "ring job" not a complete rebuild.

As long as you're willing to take the chance of having to do the work all over again if the ring job does not "take" then there is absolutely nothing wrong with doing a simple ring job.

Plenty of old tractors have had their lives extended just pulling the pistons, honing the cylinders, and installing new rings. If you were putting the tractor out in the field and working it hard every day for 10 hours a day, then it would not be a good solution. For a tractor that only sees light occasional use, there is absolutely nothing wrong with a simple ring job.

The oil pan needs to come off to access the crankshaft to remove the connecting rods so the pistons will come out. On an N series, I have no idea if this is possible without removing the engine from the tractor.

You will need to make sure that the cylinders do not have a ridge worn in the top. Severely worn cylinders won't take a ring job. If there is enough of a ridge at the top of the cylinders you will need a special tool called a ridge reamer to get the pistons out. The ridge will catch the rings and not let the piston come out. Figure on replacing sleeves and pistons if there is that much of a ridge.

Also make sure the rod and main bearing caps have a number stamped on them and write down which way they run from front to back and what side the number is on. They need to be put back in that same order.

You may want to ask some questions on the Ford 8n,9n,2n forum for specifics. Disassembly is very important as Danny Prosser mentioned.

You do have to remove the engine as the oil pan is most of the frame of the tractor. First remove front axle then seperate engine from transmission. Do you have the .090 cast sleves, good for just honing and reringing. The .045 steel sleeves are not good for that as they are too thin to stand honing and are likely cracked as well. That is the way my 9N was. And make sure you replace distributor bolts with the exact bolts in same place with the lock washers on them. My tractor had a knock in and was told it was a piston slap by mechanicks but it turned out the bolts were not put in correctly and were hitting cam gear and cutting a grove in it.

Thanks so much for the input. I have more questions and answers Ill post this evening when I get off of work. Maybe I just need to do the valves? Im doin the project as money and time allows. I have been talking with Dan Gingell from J&D productions that make the YouTube videos and sell a lot of parts for old tractors. Bad thing is he charges 15$ per phone call for information. And I dont hVe anyone local here to get advice from.

Replacing rings in an engine with worn cylinder bores usually doesn't work. The cylinder bores need to be round and straight (no or little taper) and properly honed to seat new rings. Measuring a cylinder to determine if it will accept new rings is a job that takes a moderate amount of skill and is best done with a bore gouge. It may work if the cylinder bores can be cleaned up with a rigid hone, an actual rigid hone not a glaze breaker. Then there is the question of worn pistons, especially in the ring grove area. It actually takes a fair amount of skill and knowledge regarding engine rebuilding to successfully re-ring an engine.

Youtube has some good videos of how to overhaul engines.

At least you are starting out on a fairly simple motor. Like someone else said, the internet has a lot of information. Stan

Its good you are keeping one away from the scrapper. While this may be impossible, I strongly urge you to have this first one done by an experienced tech and watch over his/her shoulder while being an apprentice and ask many questions and take lots of notes. It could mean the difference between a successful rebuild or an engine failure. Good luck.

Get you a good college textbook read it understand it and also get the factory service manual and follow it to the letter
Textbook