Low compression / weak cylinder

[4wheelfurry]

That would be an assembly error at 40 hours, at 600 it is not. Sounds like ether damage and you had better pull #1 and #2 and inspect them.

I talked to my friend that used it he tried to start it on a gas rag. They way the intake mani is positioned it shoots directly in over #3 cyl head runner. #1,2 are further away. But the rings are only available as a whole kit so I will have the rings set to do them all. Will prob pull 1,2 and re-ring the whole thing.

 

[RickB]

Piston is out. Broken second ring and middle lan. Which is quite unusual, pre-detnation usually effects the top ring and lan.. top ring and oil ring were both free and fine. No chunks missing or even big scratches to the piston beats all I ever seen. Assembly error perhaps? Anyway I have one bad push rod too so all parts ordered. Will clean this weekend and wait reassembly. View attachment 631383

Detonation pressure on the top ring broke the ring land below it. The chunk of ring land took out the second ring. Pretty typical for the circumstances.

 

[HarryVanderpool]

I talked to my friend that used it he tried to start it on a gas rag.

And of course, he's insisting on paying for the repairs; right?
I NEVER borrow or loan.
It ALWAYS ends like this.

 

[4wheelfurry]

LOL yea that isn't how it works. But I have used his tractor many times over the years he has a much larger old Ford as well as some of his other equipment. To be fair he's a diesel guy (pickups, buses, semis, equipment) and starts them all on gas rag when they won't crank. But you can bet I'll never let him forget!

 

[HarryVanderpool]

Not to flame you, but I just don't get it.
The 1540 is THE EASIEST, fastest starting tractor on the planet.
Mine has 4 times the hours as yours.
You glow the plugs for 6 seconds and then you barely hear the starter and it fires.
A gas rag? Why?

 

[4wheelfurry]

Read my above posts, fuel shut off solenoid burned out and he didn't know why it wouldn't start so he tried to get it running. I wasn't told until all attempts to get it going failed.

 

[HarryVanderpool]

Dang it......

 

[Sportsman762]

If you look at the piston you will see that the land is cracked downwards with the narrow part at the top and the wider part at the bottom. This is a clear indicator of detonation as Rick B has stated. What are you plans to address the scratches in the bore? The engine is a parent block, and it appears that they do not offer an oversized piston. This is a sucky situation for you. In Louisiana there should be no need for any type of starting aid ever required for a healthy diesel outside of glow plugs.

The prior owner of my MF used either too much and wrecked all the rings and pistons. I had to rebuild the engine, however since it was sleeved it was not too bad, and Perkin parts are cheap.

 

[4wheelfurry]

The scratches in the bore are actually pretty light I've assembled much worse so I'm just going to put it together and roll with it. As far as starting you are correct down here where I live I never even have to run the glow plugs even in the winter.

 

[rScotty]

LOL yea that isn't how it works. But I have used his tractor many times over the years he has a much larger old Ford as well as some of his other equipment. To be fair he's a diesel guy (pickups, buses, semis, equipment) and starts them all on gas rag when they won't crank. But you can bet I'll never let him forget!

Sounds like your friend learned a few new things too. To be fair to him, a burnt out fuel shutoff solenoid isn't the first thing that most people would look for. That's a good argument in favor of a transparent fuel bowl that is easy to see, but there are motors that don't have that.

That's a real good photo. Thanks for pulling the piston & posting that. I also agree that RickB nailed the cause. The upper part of a piston has a smaller diameter than the lower part, so it is likely that the first thing the detonation ether/gasoline expanding gas front sees is the compression ring which then gets forced down against the land below it.

I believe I'm with you on reassembly as is. I've seen worse scratches in engines that were running fine when disassembled.

Only a couple or more questions: How did you get the piston so clean? And what bent the push rod? Is there any wear step in the cylinder at the top of the ring travel? And do you plan to do a light hone or no?

rScotty

 

[4wheelfurry]

...
Only a couple or more questions: How did you get the piston so clean? And what bent the push rod? Is there any wear step in the cylinder at the top of the ring travel? And do you plan to do a light hone or no?

rScotty

The piston is exactly as it was removed I didn't clean it in any way. Actually the whole engine is this clean I really didn't even get that dreaded diesel oil stained in my hands lol. Guess low hours and good maint is to thank..
As for the push rod it isn't bent the lower end is a male "ball" socket but the top is a female "bell" socket. That bell had come un-pressed from the push rod tube and it separated but it couldn't come apart because it was held squished together... Ever since new I heard a faint noise in the valvetrain but it always ran fine. So when I pulled the rocker rail one of my push rods fell apart and then I know what the sound was lol.
And zero ring grove not even any carbon build up at the top, the piston pushed right out.
Over the years I've built hundreds of small engines mainly ATV and motorcycle engines. Along with quite a few autos but very few diesels I'm just not a fan of diesel grease lol. Anyway I have learned if the cylinder looks good its best not hone it just leave it be. I well understand honing is a hot debated topic and I understand the purpose of what honing does but it also removes material and IMO the oil ring is designed to wipe the oil off anyway. The only time honing is needed is after a bore to rid the screw process of the bore machine but in a perfect world a smooth cylinder is best for a oil ring to work... And I don't buy the wear pattern idea that new rings won't seal because the old rings had a wear pattern relationship with the cylinder I've built enough engines (not honing) to know this isn't true.

 

[HarryVanderpool]

Interested in how the story ends.

 

[rScotty]

Interested in how the story ends.

Me too. It sounds like 4wheel knows his mechanicals. Mine don't ever seem to be as clean as his is. I agree; much nicer to work on a gasser or propane engine.

That push rod construction with the bell and ball swaged into a tube is a popular way to manufacture a push rod. I've seen them with loose ends myself, and wonder how common it is. I doubt that it could cause a problem, but could definitely be the source of some confusing valve train noise. I once took apart a British MC engine in which ALL of the push rod ends were so loose I wondered if it was deliberate.

On cylinders and rings, I've honed and not honed and slightly honed... Frankly I've never been able to determine if honing makes any difference. I don't believe I've ever had a set of rings "not seat" in a rebuild where the piston-to-cylinder clearance was reasonable.

In fact, I'm always surprised at how much you can "get away with" in a repair and still come out with a good running and long lasting repair.
rScotty