Brand new L2501 started making a nasty noise at 6 hours

[sd455dan]

The plot thickens and we were all wrong.



There was some kind of metal FOD in one of the cylinders. It trashed the cylinder, head, valves, and piston.

Waiting on pictures now, Kubota is apparently sending someone up to investigate.


Also, they've already approved a new engine, so the shop is waiting on that.

Wow - foreign metal in a cylinder on a new tractor that ran perfect for 6 hours??

Pictures would be interesting for sure. Would like to see the Valve and Seat faces to see if it really came thru the intake port. Is the piston crown still fully intact?? Yes the plot did thicken

Glad to hear Kubota is sending a NEW engine.

 

[Diggin It]

I want to congratulate you on having a dealer who can pick up your tractor late morning one day and by first light the next day have removed the head, discovered the problem and have a new engine on order. !!! Post their name and give them some well-deserved recognition.

I have a feeling they were as curious as any of us. My LS dealer did more or less the same thing with my traction issue, but of course they didn't have to do that much disassembly.

 

[JWR]

I want to congratulate you on having a dealer who can pick up your tractor late morning one day and by first light the next day have removed the head, discovered the problem and have a new engine on order. !!! Post their name and give them some well-deserved recognition.

Very true. Any/all Kubota dealers SHOULD do exactly that, go to battle stations immediately when a brand new tractor with only 6 hours has an infant mortality of some sort. Hard to say how many really would. Good idea to publicize the excellent response. I have no question that Kubota will make all that right.

Looking like a piece of welding rod is wild/alarming of course. Maybe it is a piece of a piston ring, maybe a fragment of casting debris, maybe a chunk of the piston itself, maybe something left loose in the intake area and sucked in during running? Be very interesting to find out. One strange thing is that most mfrs run up the engines and do at least a quick running test on it before in goes into a finished tractor. Wonder why it did not show up then? That's why I'd lean slightly toward a speculative guess at something being sucked in via the intake a little later in the sequence.

p.s. : Having trashed so many things -- piston, head, etc. it may be nearly impossible to figure out what came first and what was a subsequent victim.

 

[diesel85]

I want to congratulate you on having a dealer who can pick up your tractor late morning one day and by first light the next day have removed the head, discovered the problem and have a new engine on order. !!! Post their name and give them some well-deserved recognition.

It was probably how the OP handled the situation.

In any event, interesting scenario. -- It can happen!

 

[goeduck]

I had a liner break loose and about 1/4 of the liner ended up getting smashed by the piston into the head. Sounded just like your engine did. Kubotas do not have liners so that is not it but the effect is the same. My head magnafuxed fine so I dodged a bullet. Glad to hear they are giving you a new engine.

 

[MHarryE]

I thought that rap was too sharp to be a bearing. Had something similar happen on a prototype engine. It ran fine for about 36 hours and then had a similar sharp rap noise. When we tore the head off we found the head had broke off a valve. As it was built as a prototype and not production, it was more prone to mistakes. The timing gears were assembled 1 tooth off. New computer controlled timing compensated so it made full power but valves being slammed by pistons couldn’t take the beating and one head broke off causing a similar noise.

 

[robertm]

Arcli9ht, didn't you post prior to purchase about your dealer dragging their feet on the sale, you couldn't pick it up without a tow vehicle upgrade, and had a bunch of concerns about the dealer? Didn't someone say the implements delaying the sale was "service" and that spoke volumes?
Well, unless I'm confusing you with someone else, I'd say after all the concerns, your dealer certainly stepped up to the plate. And some say "I've never had to take mine back to the dealer in 2,500 hours". Imagine the extra hassles if you had purchased from another dealer. Glad you have a winner there. Good luck and hope to hear you working that rig again real soon.

 

[goeduck]

I had a liner break loose and about 1/4 of the liner ended up getting smashed by the piston into the head. Sounded just like your engine did. Kubotas do not have liners so that is not it but the effect is the same. My head magnafuxed fine so I dodged a bullet. Glad to hear they are giving you a new engine.

I listened to the post again.. yes, the that is exactly what I heard in my situation. I shut mine down immediately. Very nice to see Kubota atepping up so fast. Shlt happens in the factory, there is always the potential of something like this happening.

 

[auroraproject]

My jaw dropped when I saw these. It's amazing how much damage something the size of a fence staple can do. Also amazing how little clearance is in these engines, they're real marvels.

It's definitely not part of the cylinder, piston or liner.


With that huge hump in the air intake, I have a hard time believing this wasn't in the head or in the cylinder from where it was manufactured. Poor kid never had a chance.

 

[auroraproject]

Arcli9ht, didn't you post prior to purchase about your dealer dragging their feet on the sale, you couldn't pick it up without a tow vehicle upgrade, and had a bunch of concerns about the dealer? Didn't someone say the implements delaying the sale was "service" and that spoke volumes?
Well, unless I'm confusing you with someone else, I'd say after all the concerns, your dealer certainly stepped up to the plate. And some say "I've never had to take mine back to the dealer in 2,500 hours". Imagine the extra hassles if you had purchased from another dealer. Glad you have a winner there. Good luck and hope to hear you working that rig again real soon.

I did, and it is. I'd move their name from that thread to this if editing was allowed.

Shame after all that time the tractor was a dud, but they had it picked up the first business day after I emailed them on Sunday and torn apart that same day.