400 series wet sleeve o ring grooves

[1967806]

Been seeing a fair share of failing o rings lately on several engines with recent overhauls. Low hours and take the sleeves out and o rings are already brittle and flat. Been wondering if the o ring grooves in the liners ever used to be radiused and not cut square like they are today? 

Also makes me wonder if materials are lacking something now days in the rubber in the o rings.

My last overhaul I got some o rings from cat to try. According to parts chart they were supposed to be oil and glycol resistant. Didn't get much trial out of that one though as a valve spring broke and swallowed valves after about 25 hours. 

[snoshoe]

Look closely in the block where the top oring sets. My money says there will be erosion around the top edge. That allows rubber to squease out reducing pressure on the tapered face. There is quite a bit of pressure there to seal. The controversial part is as far as I can figure the other two orings are just shock absorbers and sound deadeners. If top ring leaks it doesn't even slow down going past the other two. Counterbore repair sleeves are called for. Finding a shop to install them correctly is almost harder than paying for the job

[HydroTek]

Top oring was red
the bottom 2 were black

Pretty sure the groove had a  radius

-- I have an old sleeve over at the other Farm 
will take a look if I remember 

Still need to get SnoShoe those resistor ohm values 
should be a box with several of those resistors 

[dale560]

Drill a hole in block like a JD let the antifreeze escape. Just kidding. I have had fairly good luck with aftermarket orings on the Cummins I have fixed the last few years. 

[dale560]

John Deere had different color orings as far as I remember IH had 3 black orings.

[1967806]

6 hours ago, HydroTek said:

Top oring was red
the bottom 2 were black

Pretty sure the groove had a  radius

-- I have an old sleeve over at the other Farm 
will take a look if I remember 

Still need to get SnoShoe those resistor ohm values 
should be a box with several of those resistors 

Glad to hear that. All kits Ive had last many years have all had black o rings. All aftermarket kits. Thinking we might be on to a junk parts rant here. 

[1967806]

6 hours ago, snoshoe said:

Look closely in the block where the top oring sets. My money says there will be erosion around the top edge. That allows rubber to squease out reducing pressure on the tapered face. There is quite a bit of pressure there to seal. The controversial part is as far as I can figure the other two orings are just shock absorbers and sound deadeners. If top ring leaks it doesn't even slow down going past the other two. Counterbore repair sleeves are called for. Finding a shop to install them correctly is almost harder than paying for the job

Yep, I've seen that and had to have blocks repaired. But been seeing it on prefectly fine blocks too. 

[1967806]

6 hours ago, snoshoe said:

Look closely in the block where the top oring sets. My money says there will be erosion around the top edge. That allows rubber to squease out reducing pressure on the tapered face. There is quite a bit of pressure there to seal. The controversial part is as far as I can figure the other two orings are just shock absorbers and sound deadeners. If top ring leaks it doesn't even slow down going past the other two. Counterbore repair sleeves are called for. Finding a shop to install them correctly is almost harder than paying for the job

One I tore in to was one of my own. 466 in my 5288. Overhauled it in frame 4 years ago. Number 3 o ring counterbore had an issue but we cobbled it to get it back together becasue it was april and we needed it in the field. Last fall it started that famous blowby steam. Before I tore it down I pulled the pan and could see water was coming from number 2. Number 3 was fine. Number 1 and 2 liners came out of the block by had. The other 4 wasnt very hard out either. All 3 or rings on all 6 liners were so brittle and hard they broke when I tried to get them off with a pick. Number 2 hole in the block looked fine. 

[dale560]

39 minutes ago, 1967806 said:

Glad to hear that. All kits Ive had last many years have all had black o rings. All aftermarket kits. Thinking we might be on to a junk parts rant here. 

Way back to the first IH kit I installed in 1989 the orings were all black. I could be wrong. The jd kits had red and black. I will find the engine manual one day to make sure.

[Binderoid]

I would venture to say that the condition of the grooves would not have any bearing on the hardening of the o-rings. If the grooves were the problem they would show evidence of nibbling or cuts, and still be soft.

Ive had Detroits that had loose sleeves in the block,  and this always took out the fire ring and burned a nearby coolant seal.... but the bottom of the sleeves never  leaked. 

I think you're on the right track with Cat o-rings.

[FarmerFixEmUp]

The kit I had issues with years ago from Reliance, the orings dumped anti freeze in the oil within 200 hours. the couterbore sleeves were replaced first time around, took the orings to the machine shop and they were just crumbling apart.  He said it's like they had brake fluid on them, I had used the JD oring soap. New orings from IH and no problem since. 

[HydroTek]

Top groove is also a different depth than the lower 2 

The red oring was on some kits -- we got kits from IH, but also other places 
I dont remember which had the red oring 
in the early years with the oil consumption problems -- kits were in short supply 
I have seen 6 or 8 tractors down in our shop at one time , from either engine or rear end problems 
worked on them in the isle way or in the warehouse a few times 

Not the largest dealer around -- the tractors were just that popular in our area 
I am sure others have similar stories 
For the first couple of years when the '66 came out we were selling a bunch of them 
tires set, weights/fluid, washed / waxed -- Boss liked to run them on the dyno -- sometimes 2 or 3 a day between 2 of us "school kids" 

Common for the lower 2 orings to get "crunchy" 
usually a fail of the top ring can be seen in the block counter bore
I have used JBweld in a pinch and it worked to smooth out pits 

[acem]

If you know the specifications you can buy o rings yourself.

Exact size, normally a dash size.

Material 

Hardness 

Quality level.

You can buy arrospace quality o rings of your willing to pay the price. Of course the challenger explosion was a famous o ring failure.

 

 

[TeachersPet1066]

12 hours ago, acem said:

you can buy o rings yourself.

Exact size, normally a dash size.

Material 

Hardness 

Quality level.

Correct.  We would order them from McMaster for the 466 in the pulling engine.

[acem]

I get most of my o rings from RGA in Fort Smith. Very knowledgeable and good prices.

Here's a good online source. They offer aerospace quality o rings if you need them.

https://www.theoringstore.com/store/index.php?main_page=index

And good reference material 

https://oringhandbook.com/#find-oring

 

[1967806]

On 9/13/2026 at 2:25 PM, dale560 said:

Drill a hole in block like a JD let the antifreeze escape. Just kidding. I have had fairly good luck with aftermarket orings on the Cummins I have fixed the last few years. 

Got one of them that haunted me for a few months untill it finally sealed up. 

[1967806]

I still think if the grooves in the liners were rounded the o rings would seal better in the block. At least one side of them would not get flat. 

[dale560]

2 minutes ago, 1967806 said:

Got one of them that haunted me for a few months untill it finally sealed up. 

Of all the jds I have done never had one leak out the holes afterwards but we spent a lot of time cleaning those grooves in block. I had 2 2510 jd gas tractors I pulled pistons and sleeves together to change orings after about ten years of previous overhaul. Left pistons in sleeves knocked them up with a brass operating rod from a fire hydrant and reinstalled with new orings and rod bearings cleaned and same place.

[1967806]

36 minutes ago, dale560 said:

Of all the jds I have done never had one leak out the holes afterwards but we spent a lot of time cleaning those grooves in block. I had 2 2510 jd gas tractors I pulled pistons and sleeves together to change orings after about ten years of previous overhaul. Left pistons in sleeves knocked them up with a brass operating rod from a fire hydrant and reinstalled with new orings and rod bearings cleaned and same place.

What do you use to clean the grooves? I was never to satisfied with the way a wire brush on a die grinder left things. But I never knew what else to use. Pretty sure that left some pitting in the bottom of that groove. 

[dale560]

11 hours ago, 1967806 said:

What do you use to clean the grooves? I was never to satisfied with the way a wire brush on a die grinder left things. But I never knew what else to use. Pretty sure that left some pitting in the bottom of that groove. 

Oring pick. To scrape everything and a cotter pin screwdriver type puller. Then a wire brush mounted on an extended shaft run with air drill. Two types of brushes a harder bristle then a softer to finish stuff up. Water quality in areas though makes a huge difference for pitting. If they hard ground water of high mineral and conductivity it pits bad.

[acem]

Water quality effects so many things.