I am working on a TO30 that has been plagued with oil building up in the combustion chambers. I put in new oil guard seals on the intake valves but that did not help, so I pulled the head. I found that the pistons were installed with the word "front" and arrows pointing toward the back of the tractor which puts the T slots and oil holes on the wrong sides. The pistons and sleeves look OK (like almost new). I am thinking about honing the sleeves and putting the pistons in correctly with new rings. Seems like backwards pistons might be the cause of the oil fouling. Anyone with some experience care to comment? Thanks.
- Thread starter John (AR)
- Start date
John Deere D
Well-known Member
As the PISTONS are in stalled 180 deg out you may wish to verify if the Connecting Rods were installed properly (they also may be 180 deg out)?. Also check to see if the PISTON RINGS are installed properly? Rings do have a proper orientation once installed on the Piston. They should have a DOT or some other identification on the ring?
Steve@Advance
Well-known Member
Not real sure what backward pistons would cause. Suspect the rods being backward would cause some type oiling problem...
Look the oil control rings over when you get it apart. Probably they were improperly installed, like the expander springs were overlapped instead of butted together. When you get the new rings, check the end gaps and the land clearance. Both are critical for rings to seal properly.
Might want to double check the rod and main bearing clearances while you're in there... (And everything else since such an obvious mistake was made on the pistons, anything is possible). Loose bearings cause more oil to be thrown off the crank, causing more oil to hit the cylinder walls.
Other obvious stuff... Right dipstick, right oil level? Is the crankcase vent tube and baffle clean? Even though you added the intake stem seals, good time to take the valves out and check the stems and guides, seals can only do so much.
Remember, the cylinder liners just sit in the block. If you're not taking them out, be sure to bolt them down while the head is off!
Look the oil control rings over when you get it apart. Probably they were improperly installed, like the expander springs were overlapped instead of butted together. When you get the new rings, check the end gaps and the land clearance. Both are critical for rings to seal properly.
Might want to double check the rod and main bearing clearances while you're in there... (And everything else since such an obvious mistake was made on the pistons, anything is possible). Loose bearings cause more oil to be thrown off the crank, causing more oil to hit the cylinder walls.
Other obvious stuff... Right dipstick, right oil level? Is the crankcase vent tube and baffle clean? Even though you added the intake stem seals, good time to take the valves out and check the stems and guides, seals can only do so much.
Remember, the cylinder liners just sit in the block. If you're not taking them out, be sure to bolt them down while the head is off!
Thanks for the comments and suggestions. Here some photos of the pistons as they look right after removal. There is no carbon on top of them, but lots of oil. I am not knowledgeable about pistons and rings, but the oil control rings are worn and flaking off in places (except the one of different design) and they do not have any spring in them like the compression rings do. Also are the compression rings installed correctly? They have no dot that I can find, but it seems like the wide part of the bevel should be up(?). Also the gaps were not on alternate sides of the piston. The pistons look OK to me with good lands and grooves. I will measure them to be sure before reusing them. They are standard size. The connecting rod oil spray holes are on the correct side, away from the cam. The con rod bearings and journals look OK. The cylinder walls are glazed but not scratched up. So I might hone them and put in new rings and go on. Does that sound reasonable? I think the previous work was not done right and the saving grace was that there were other issues that kept the tractor from running and causing more damage.
<image src="http://forums.yesterdaystractors.com/photos/mvphoto20597.jpg"/>
<image src="http://forums.yesterdaystractors.com/photos/mvphoto20598.jpg"/>
<image src="http://forums.yesterdaystractors.com/photos/mvphoto20597.jpg"/>
<image src="http://forums.yesterdaystractors.com/photos/mvphoto20598.jpg"/>
Steve@Advance
Well-known Member
From the pictures, the oil rings appear to be severely worn.
Yes, you could probably get by with turning the pistons around, honing it, and replacing the rings. Most of these old tractors don't get worked real hard, but if this is a working tractor, a new set of pistons and liners would give a more permanent fix.
If you do hone and ring it, try to find some iron rings if possible. They seat easier, more forgiving of "less than perfect" conditions than chrome or molly rings.
The new rings will come with installation instructions. Follow those instructions over the manual or any other advise.
Yes, you could probably get by with turning the pistons around, honing it, and replacing the rings. Most of these old tractors don't get worked real hard, but if this is a working tractor, a new set of pistons and liners would give a more permanent fix.
If you do hone and ring it, try to find some iron rings if possible. They seat easier, more forgiving of "less than perfect" conditions than chrome or molly rings.
The new rings will come with installation instructions. Follow those instructions over the manual or any other advise.
Chrome rings are more forgiving of an out of round bore and dirt,but they are harder to seat. If I was to make a recommendation for rings I would get a set of Hastings rings. That is who made the oil ring on the oddball piston. They are fair priced and good rings.https://www.hastingsmfg.com/RingFin...lated Cylinders)(Listed by Cylinder Diameter)
Similar threads
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.
Copyright © 1997-2024 Yesterday's Tractor Co.
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy