Blew Hydraulic hose on FEL, instant drop.

[Industrial Toys]

I am trying to understand how the T would matter. Both sides of the cylinder or cylinders, no matter how many in paralell are closed at the valve when in the neutral position. So if the circuit under pressure failed, the other side would go into suction and that "should" be substantial.

 

[newbury]

My B7800 has been sitting out in the desert sun for 15 years. I have looked at the loader hoses several times as they look like they have hardened. Would it be prudent to replace all the loader hoses?

I asked about the same 8 years ago when I bought my 1995 M4700. The general TBN consensus then was "go till they blow". I've had to replace about 4 or 5 hoses overall so far due to slow leaks and snags on limbs (I work in the woods sometimes).

If I had replaced them all back then now ALL would be 8 yrs old and at least one would have been replaced again due to "snagging".
It would have been prudent to have replaced them all if I needed the tractor for making money but I don't.

 

[cqaigy2]

I've had two hydraulic lines go in the almost 20 years of use, one was to one of the hydraulic motors on the tram circuit, the other was this one, on the FEL. I don't believe the rubber on the outside of the line has much effect on the operation of the line, so i'd be reluctant to swap them all out because the outer covering was cracked, if that is what you are referring to about hardened.

 

[MHarryE]

I’ve wondered why they don’t have safety stops on SCUTs, CUTs, and ag tractors. All construction backhoe loaders I’ve seen have safety stops. My Kubota CTL has a safety stop and instructions on its use being a 2 person operation. Raise the loader, have your assistant secure the stop in place, and only then will it be safe to exit. Some maintenance requires the loader to be raised. It bugs me that when my tractors have been at the dealer, the tech will raise the loader to the max giving extra room to work. I have props I use but why is it possible to have a safety stop on construction equipment yet not supply them for consumer and ag equipment?

 

[4570Man]

My M59 has a stop on the loader to keep it suspended in the air. I don’t know why they don’t offer it on all tractors. Aside from safety when working on it it’s useful for parking the machine in a crowed garage or in too short of a trailer. It’s only a manual stop and does nothing if a hose blows while in operation though. I was considering putting a ball valve on the cylinder port that I could close to keep it held up. The ball valve would benefit from any height locking vs full height only or you could close it part way for man lift use. At least you could have a slowish decent that way.

 

[npalen]

I am trying to understand how the T would matter. Both sides of the cylinder or cylinders, no matter how many in paralell are closed at the valve when in the neutral position. So if the circuit under pressure failed, the other side would go into suction and that "should" be substantial.

It seems that would be true but I'm wondering what caused the OP's loader to fall when the hose failed. He said it "dropped like a ton of bricks".

Edit: I'm wondering if its possible that the extreme vacuum, on the rod side of the cylinder when the hose failed, could shift the valve spool and cause the drop? There would be little if any pressure on the other side of the spool with the failed hose.

 

[npalen]

How could the load fall if there is a vacuum to supposedly hold it up? You guys surely have some thoughts on this.

 

[4570Man]

How could the load fall if there is a vacuum to supposedly hold it up? You guys surely have some thoughts on this.

A perfect vacuum is like -14.5 psi. Not nearly enough to hold the load.

 

[Peter 315]

Its only going to fall as fast as the hyd oil comes out the hose . It has to force the oil out ..

 

[5030]

Pretty easy to fab up a rod stop and use it. Reminds me about before I retired, I ran a 3 axle roll off and hauled scrap steel from our plants to the steel mill, every day, 6 days a week. Always heavy too...lol

Was pulling up a big box of tails and had my stick raised almost all the way up and the main hose to the lift cylinder let go and it shot hydraulic fluid about 60 feet straight up and it came down on me, the parking lot and the employees cars. Went all over and dumped about 80 gallons in a few seconds and of course the stick came down real fast too. What a mess. Glad it was a gravel lot. Kept the dust down for a while. Didn't hurt the cars or me though I needed to change uniforms. All the employees cars that got doused got a free car wash from the company. Gotta love the roll off business.:laughing: