2040 #1 low compression- did ether do this?

[fixitforfree]

After finding our 2040 had low compression in cylinder #1 (210psi vs 360psi in #2) I pulled the head and piston today. Given I learned my father in law used ether to try to crank it when we ended having an injector pump problem all along I fully expected a hole in the piston, broken ring land or broken ring. I found none of this. The cylinder looks great but look close at my attached photos of the piston. The top and middle ring have very noticeable pits in them. They are easily seen and can be felt with your finger even though the pictures don’t reveal the pits too well. Are these pits from over use of ether that one time and are these pits enough o cause low compression in that cylinder? I was hoping to find a more obvious reason for my low compression. Right now I’m scratching my head wondering if this is it. Suggestions?

 

[used red MN]

I would say no on either. It looks to me like it may have set with water or antifreeze in the cylinder, is there any sign of this in the sleeve where it may have set in one place on the cylinder wall? It may be that some type of coating or plating like chrome is failing or flaking off in those spots.

 

[Mcrafty1]

I don't see enough damage to cause 150lbs of compression loss, but why does it look like the back side of that piston skirt in the first picture is missing? What does the valves look like? The head in general?

 

[Jim.ME]

Let's see the other side of that piston.

 

[fixitforfree]

Tractor wa bought new by our family in 81 or 82. Does not use oil or lose water and never has. Has always cranked immediately regardless of temp outside but we live in east Texas. Cylinder looks great. I have attached photos of the cylinder and more of the piston. There is no wear that can be felt in the top of the cylinder. I have no dismantled the head yet but just see valves from the bottom side dot have any obvious damage such as cracks or breaks. We got in this place because the tractor quit one day after about 30 minutes of use just like the due had been shut off. No warming, no noises just quit. Turns out the main shaft in the pump broke. Got that fixed and got it running no problem but #1 now has low compression. I also notice the top of #1 piston has a gouge on top that is fresh. Looks like something limit enough to gouge it which is noticeable by eye then went out the exhaust I assume. I attached a pic of that as well. I’m just wanting to put my finger on the low compression issue but haven’t yet. Maybe the answer lies in the head that I haven’t torn down yet.

 

[Jim.ME]

Ok, the piston is all there the angle of the first phot left the question of whether or not some of the skirt had broken away.

 

[fixitforfree]

You guys have any suggestions other than me checking the head before deciding a path forward? Aside from maybe a valve issue I just don’t see why I have a sudden loss of compression in that cylinder unless those pits in the top and middle ring are the reason.

 

[wore out]

I would say no on either. It looks to me like it may have set with water or antifreeze in the cylinder, is there any sign of this in the sleeve where it may have set in one place on the cylinder wall? It may be that some type of coating or plating like chrome is failing or flaking off in those spots.

I agree. Those rings are worn & pitted, the oil control ring is no longer "sharp".

Also, it would have been GREAT to have done even a basic cylinder leakdown test BEFORE tearing it down to determine if the valves were "holding" and/or if the leakage was all past the rings.

I can't imagine that the rings on the other pistons look much better.

 

[MSD]

You have the head off you might as well run it into a machine shop and get it checked and refurbished. Make sure they have JD's before so they know about setting the valve head height.

 

[used red MN]

You guys have any suggestions other than me checking the head before deciding a path forward? Aside from maybe a valve issue I just don’t see why I have a sudden loss of compression in that cylinder unless those pits in the top and middle ring are the reason.

A quick check for valves is set the head on its side and fill the ports with diesel or solvent and see how fast it leaks out of the valves on the bad cylinder compared to the one that had good compression. Repeat on the intake side, might take a bit of fluid to fill the head since it has a cast in common intake.

 

[fixitforfree]

For sure I have it checked but any ideas on the root cause of my low compression based on details I’ve given and the photos? Something happened in #1 and I can’t explain it. I see no evidence of what is causing it. This engine was super tight until this incident. It cranked quick with #1 low on compression. My initial thoughts are to put new rings in #1, hone the cylinder, have the head worked and put it back together.

 

[joeysmith]

You guys have any suggestions other than me checking the head before deciding a path forward? Aside from maybe a valve issue I just don’t see why I have a sudden loss of compression in that cylinder unless those pits in the top and middle ring are the reason.

Tip broken off the injector?
Seen washed out cylinders from a bad injector look similar

 

[fixitforfree]

Tip broken off the injector?
Seen washed out cylinders from a bad injector look similar

Maybe so. Problem is when we had the initial problem with the injector shaft broken I had no idea I had this low compression issue also. I took the injectors and pump to a shop. They rebuilt the pump and swapped my injectors for new ones so I never looked that close at the tip. I wonder if that injector tip is what damaged the top of that piston? I still have no idea even if that is what happened and ruined my injector pump shaft how did it also kill compression in that cylinder? All of this happened at the same time. Still scratching my head.

 

[Fixingfarmer]

With a broken tip it’s possible it have pumped enough in to miss and smoke like crazy for a second and then cause it to lock and that would be hard on everything. I’m surprised the tip isn’t laying anywhere might want to check the manifolds. It’s the right shape to be an injector. Broken Off valve stem would be the other thing that shape

 

[buickanddeere]

After market high compression pistons and set the valves high for max compression. Nobody looks at camshafts, cam followers , oil pump drives and oil pumps until they completely fail. I would not be surprised if there is valve train problem on that cylinder.

 

[fixitforfree]

After market high compression pistons and set the valves high for max compression. Nobody looks at camshafts, cam followers , oil pump drives and oil pumps until they completely fail. I would not be surprised if there is valve train problem on that cylinder.

I'll be removing the valves soon to take a closer look. So far I've only visually looked at the valves and nothing is obvious but maybe when I remove the springs and can see the valves closer I'll be able to see something. Thanks.

 

[fixitforfree]

I removed #1 valves and see nothing out of the ordinary. Seats and valves look fine and in good shape. Very little play could be felt between valve and guide. Outside of the pitting on that top and middle ring I don’t see a thing that could result in such a large drop in compression so quick. Still scratching my head. Given this tractor won’t be sold and will remain in our family I could go all in and buy a kit with new pistons, rings, liners, gaskets and have the head reworked. Or it seems simply replacing the rings only in #1 would work as well. In a my years working on engines I have never seen such a dramatic change in a motor like this one had only to tear it down and still wonder exactly the problem lies. Usually it’s not hard to find but this stinker has me puzzled.

 

[used red MN]

What’s this in the photo? Do you have a Scotch Brite pad or use some finer emery cloth. Go around that valve seat face quickly and wipe it clean, just enough to clean of the good face surface and leave the black in pitted areas. Then repost some pictures of it preferably not on a red background. That valve obviously wasn’t sealing the best. Did you check to see if it had adequate valve lash before you pulled the head? It doesn’t look “sucked down” like clearance would be a problem but you never know if some yahoo set it wrong.

 

[fixitforfree]

Valve lash was spot on plus no one has ever messed with it. Valve cover has never been off this tractor in its 5000hr life. We bought it new. Also, no flat cam lobe as the rockers rocked fully on all valves. I looked close at this before head removal. Let me clean that valve as you said with Emory cloth. Give me a little bit. I’ll be right back.

 

[fixitforfree]

Used red MN, I used Emory cloth and attached more photos of that exhaust valve. It has pitting and wear on that portion that contacts on the seat but nothing irregular in any one location. I think that in the original photo was a piece of fuzz from my paper towel I wiped it down with. I did attach another close up of the worst pitting on the top #1 ring. I think this photo better shows the depth if you zoom in than my previous photos.