hydraulic dieseling

[funwithfuel]

Recently a newbie asked a question about hydraulics and cross contaminating oil with fuel. Long story short, I and others were challenged on the subject of "Dieseling" I was also accused of being a google technician. I really don't care what you guys think of me or my experience. I DO want to point out that dieseling is a real situation. Attached are images of the barrel to head as being separated . The pics are of a dipper cylinder of a 158,000 pound machine. It sits up pretty high. Very difficult to purge air out. This is what happens . I challenge you to find these images on google or tineye or any other image search engine. They are my pics, shot with my phone. I really didn't want to get drawn into a petty argument like this. The pressures were set to spec, the machine was not digging heavy clay. It was strictly material handling, mulch, to be exact. This was not a hard working machine, nor was it abused. We replaced the first cylinder under warranty with less than 700 hours, the second , a couple hundred later. Upon disassembly of the first, we discovered the back up ring and O-ring were both disintegrated. The piston packing was burned and forced back past the ring lands of the piston. The internal seals were also deformed badly. It didn't take long to realize what happened. This was a newer machine, after repacking the first cylinder and replacing the replacement as well as diligently purging air from the circuit , no new leaks have been reported. It has been over 2 years without failure.

MODS, If this post is viewed as inappropriate, please delete or modify as needed.

 

[Junkyard]

For those who understand no explanation is necessary. For those who don’t no explanation is possible.....

Makes sense to me, for whatever that’s worth!

 

[funwithfuel]

Thanks. And its worth quite a bit

 

[Nige]

I’ve come across dieseling a number of times, specifically in the tilt cylinders of large wheel loaders. It’s a known documented phenomenon as far as I’m concerned.

 

[funwithfuel]

Well, that's the point Nige, a senior member who I thought knew better dismissed it is heresy. Like I was preaching flat earth and such. I'm cool with that. I just don't want some newbies thinking its mularkey, when it's not. I ain't calling out names, but I had held this persons input as "solid" prior to this exchange. Maybe I'm just venting like a 8itch. I don't mean to come off as such. Just trying to get the point out there is all.
BTW , thanks for your input as well. Always well thought out and backed up.

 

[RZucker]

Recently a newbie asked a question about hydraulics and cross contaminating oil with fuel. Long story short, I and others were challenged on the subject of "Dieseling" I was also accused of being a google technician. I really don't care what you guys think of me or my experience. I DO want to point out that dieseling is a real situation. Attached are images of the barrel to head as being separated . The pics are of a dipper cylinder of a 158,000 pound machine. It sits up pretty high. Very difficult to purge air out. This is what happens . I challenge you to find these images on google or tineye or any other image search engine. They are my pics, shot with my phone. I really didn't want to get drawn into a petty argument like this. The pressures were set to spec, the machine was not digging heavy clay. It was strictly material handling, mulch, to be exact. This was not a hard working machine, nor was it abused. We replaced the first cylinder under warranty with less than 700 hours, the second , a couple hundred later. Upon disassembly of the first, we discovered the back up ring and O-ring were both disintegrated. The piston packing was burned and forced back past the ring lands of the piston. The internal seals were also deformed badly. It didn't take long to realize what happened. View attachment 189181 View attachment 189182 View attachment 189183 View attachment 189184 This was a newer machine, after repacking the first cylinder and replacing the replacement as well as diligently purging air from the circuit , no new leaks have been reported. It has been over 2 years without failure.

MODS, If this post is viewed as inappropriate, please delete or modify as needed.

I'm not going to argue that it does not happen. But was this machine contaminated with Diesel fuel? Or was the presence of air and hot hydraulic oil vapors enough to cause this? No air... no combustion, I don't care what is in the circuit. In the other thread you stated it was going to happen no matter what because of the fuel contamination. (roughly 10 percent). Again... no air...

 

[funwithfuel]

Oh you got me there. No air intrusion, just fuel contamination. And I stated that if, IF air got in there, damage could occur. And I followed up by suggesting drain and fill, operate and repeat.
Good eye for detail. But no, I didn't state that it would, rather that it could, with air. And it wouldn't even need to be warm out. You're on the right page.
These pics I have posted were strictly hydro dieseling. The post your referencing was cross contamination. But yeah, it could

 

[RZucker]

Oh you got me there. No air intrusion, just fuel contamination. And I stated that if, IF air got in there, damage could occur. And I followed up by suggesting drain and fill, operate and repeat.
Good eye for detail. But no, I didn't state that it would, rather that it could, with air. And it wouldn't even need to be warm out. You're on the right page.
These pics I have posted were strictly hydro dieseling. The post your referencing was cross contamination. But yeah, it could

Not trying to have a p!ssing contest here, just stating the physics of an event like that.

 

[willie59]

No air... no combustion, I don't care what is in the circuit.

Correct. In that situation such damage would most likely be caused by cavitation.

 

[funwithfuel]

Not trying to have a p!ssing contest here, just stating the physics of an event like that.

I'm with you, you went back and re read what I posted, right? I ain't out to preach doom and gloom, just trying to help avoid something larger. You are 100% correct, no air , no bang.

 

[funwithfuel]

Correct. In that situation such damage would most likely be caused by cavitation.

And that's a critter of a different hide.
That's what I love so much about this place. Tremendous experience and knowledge from all over.

 

[580bob]

yup where is the diesel fuel in all of this and where is the deformed cylinder?? you needlessly scared the crap out the original poster in that 580 blog with your I know all about all with help of google don't come on so strong with all the technical bs when all it takes is a simple fix

 

[funwithfuel]

That's my point, I informed him of the risk, beyond that, it's his decision. When a youngin asks for help or guidance, we ought to give what's asked. I don't and won't $h!t on what someone advises someone else unless they are trying to put that person in harm's way or are blatantly wrong, then I will invite a "polite" discussion.

 

[580bob]

that's my point you went ballistic in your "guidance" and didn't need to I would call that damage cavatation not dieseling so call it what you may and carry on with all your fancy words and xplanations wherever you get them but you aren't fooling us who have been pulling wrenches and have learned by experience not by the computer

 

[funwithfuel]

Let's agree to disagree
BTW the earth is round

Google says so

 

[Tags]

A couple things, there was aquestion asked, fun responded with an answer of what COULD happen, will it, who knows, could it, absolutely. Does the op need to take action, no, plenty of others chimed in with their opinion, he should do what he thinks is the right course of action for him. Second, how is it just "computer experience" when he posted his own pics of a failure he had to repair?

I don't have a dog in this fight, but I certainly like coming here and seeing what other like minded folks have to say about their experiences, I certainly don't agree with what everyone posts, but who the hell am I to say this that or the other. I haven't been here that long, but I have seen to many fellas get tired of justifying their real world experiences and just don't help out or come around anymore. It's really a shame because there are a lot of interesting things posted here and that comes from people that have interesting experiences....not to mention all the really great free repair/diagnosis advice that gets tossed around on a daily basis....just sayin.....

 

[funwithfuel]

A couple things, there was aquestion asked, fun responded with an answer of what COULD happen, will it, who knows, could it, absolutely. Does the op need to take action, no, plenty of others chimed in with their opinion, he should do what he thinks is the right course of action for him. Second, how is it just "computer experience" when he posted his own pics of a failure he had to repair?

I don't have a dog in this fight, but I certainly like coming here and seeing what other like minded folks have to say about their experiences, I certainly don't agree with what everyone posts, but who the hell am I to say this that or the other. I haven't been here that long, but I have seen to many fellas get tired of justifying their real world experiences and just don't help out or come around anymore. It's really a shame because there are a lot of interesting things posted here and that comes from people that have interesting experiences....not to mention all the really great free repair/diagnosis advice that gets tossed around on a daily basis....just sayin.....

Wonderfully said.

 

[willie59]

I've been away from my computer for a couple of hrs, let's all keep it peaceful in here.

 

[Junkyard]

Tags you beat me to it. Trashing the man for sharing his experience because you disagree, haven’t seen it or don’t think it’s possible is a waste of time. In my humble opinion if you don’t have anything constructive to say it might be better to keep it to yourself.

There have been many brilliant guys run off here over needless drama. I love sharing and helping people on here. In turn I learn a lot myself. Should I be faced with somebody talking smack, and I have been, I have to take a step back. I consider the context, their contributions and if I possibly made a mistake. We’re mechanics, operators etc not English majors so it’s entirely possibly what we’re trying to say doesn’t come across like we want.

On the other hand when somebody is talking $hit and trying to stir the pot for no reason that’s blatantly obvious to me.....

 

[Junkyard]

Let's agree to disagree
BTW the earth is round
View attachment 189193
Google says so