New hydraulic hoses

[hdmyers]

Jeff said: "Usually the old metal fittings are used with new hoses." Great advice !? Not hardly.

That might be true in the rare case where the "metal fittings" can be simply screwed apart or together but 99% of the time crimped ends on hoses are involved and essentially they are NEVER reused !! Most of the time they can't be reused even if one were silly enough to try. The most false kind of economy to try. I have never ever seen a shop willing to screw with the old, almost certainly questionable if not outright damaged, connectors !! That is bum info.

You, the OP, were not clear that the leak is in the two hoses themselves or only at the connectors. Obviously you need to check first to see if something threaded just needs tightening. If the hoses ARE leaking through the walls of the hose or at the swaged /crimped spot with the hose end then you need to replace the entire hose and connectors as a unit. You mentioned that the hoses take a real beating -- so after 5 years replace them! And heavier duty has to be a good idea.

I am confident your hoses have permanently attached (swaged , crimped) connectors on each end and you want to have the entire leaky hose or hoses replaced lock, stock and barrel. What you want is a long-term permanent fix. And good to put on heavier duty hoses while you are at it.

Did you read the posts, or just look to give Jeff a peace of your mind? Asking for a friend.

 

[LouNY]

I have replaced literally 100's of hydraulic hoses over the years, of those I can only recall a couple that had the reusable fittings and those where on long hoses were I installed the removable fittings after cutting the old fittings off.
While I try to keep a few hoses in stock they are seldom just the right length, I'll often temporally install a long hose to get equipment back to work then order a new hose to fit.
The other option is either the local NAPA store to get one made or the New Holland dealer or the John Deere dealer to have a hose made.
I have not seen recrimpable (replaceable ferrells) fittings in our ag related area.
I just placed a second order to Surplus center for half a dozen hoses and fittings, previously this month I had ordered 4 hoses and fittings after repairing one of the four on the NH forage chopper at the farm. Got 4 new ones to install either before next summer or when the next one starts leaking then I'll remove my temporary hose that required 4 fittings to get the threads to match.

 

[4570Man]

Jeff said: "Usually the old metal fittings are used with new hoses." Great advice !? Not hardly.

That might be true in the rare case where the "metal fittings" can be simply screwed apart or together but 99% of the time crimped ends on hoses are involved and essentially they are NEVER reused !! Most of the time they can't be reused even if one were silly enough to try. The most false kind of economy to try. I have never ever seen a shop willing to screw with the old, almost certainly questionable if not outright damaged, connectors !! That is bum info.

You, the OP, were not clear that the leak is in the two hoses themselves or only at the connectors. Obviously you need to check first to see if something threaded just needs tightening. If the hoses ARE leaking through the walls of the hose or at the swaged /crimped spot with the hose end then you need to replace the entire hose and connectors as a unit. You mentioned that the hoses take a real beating -- so after 5 years replace them! And heavier duty has to be a good idea.

I am confident your hoses have permanently attached (swaged , crimped) connectors on each end and you want to have the entire leaky hose or hoses replaced lock, stock and barrel. What you want is a long-term permanent fix. And good to put on heavier duty hoses while you are at it.

It can be done. They cut the crimp band off the end and crimp another one around it. But you’d only do it it large diameter hoses where the ends are expensive or on something odd ball that can’t be located. But the diameter hoses the OP is dealing with are cheap. Just have new ones made and go on.

 

[rScotty]

Most hoses in our area are crimped together by our local hydraulic shop using new end fittings.
But because there are many similar hose end fittings and threads, I always take the old hoses WITH their old fittings along to make sure the replacement hose is made to fit.
rScotty

 

[Tony H]

Just make sure the hoe is 'relaxed' before disconnecting the hoses. You don't want something dropping on you when cracking the line loose.
Maybevinvest in Flatenut Wrenches for that better bite the basic Open end wrenches.

 

[JD4102004]

Kubota BX25LDB: After five years and only 180 hours, two of the lines from the tractor to the backhoe are leaking badly. One end of the hoses can be disconnected, the other unscrewed. I could buy the hoses rather than haul the tractor 200 miles for service. I've never worked on hydraulics. I am thinking reduce pressure to zero, remove/replace but how do you bleed the air. Also does the fluid flow out when the hoses are disconnected? Any help appreciated. I've done quick search with nil result. Direct me to info if possible.

I've had to replace 3 hoses on my 2004 3400 already with only 300 hours. It is always kept inside. My 1991 2850 still has all the original hoses with 1600 hours. It is easy to see the quality difference between the 3400 and the 2850. Kubota is not the tractor it once was6. IMO If I ever buy another tractor I will be looking at another brand.

 

[Bentrim]

Just for those who are inexperienced with Hydraulics. Hydraulic hoses are many types sizes and manufacturers. Although hoses are referred to by size 1/4 - 3/8 - 1/2 - 5/8 - 3/4 being the most common. Not that as the sizes get bigger they can carry more volume (gpm) of oil but they can handle less pressure (psi). All manufactures do not make the hose the same overall size. Usually the id is OK but the od will be different. As thickness of outer covering and whether one wire or two wire or four wire.

Now how do you use a hose with out fittings? And what type and size are they? Hose fitting are usually made in one of two types reusable and crimp on. Just as the name implies reusable fittings can be taken off the old hose and reused on a new one as long as it is the exact same type and manufacturer, otherwise you stand a chance of blowoff or they just don't fit. The same applies to crimp on fittings it is recommended to only use the same manufacturers hose and fittings and follow the crimping instructions exactly. Each manufacturer has their specific tooling and instructions on properly crimping the ends on a hose. Now as to the ends available. Do you want pipe thread, JIC, O ring, flat face O ring or some other type someone thought of. AND don't forget each of the preceding needs to be for a specific hose size and can come in different thread sizes. So you want to get in the hose making business? You will always have the wrong fittings on hand and won't be able to make just what the customer wants, Unless you can afford to stock every fitting made.

Now How about a little on hydraulic systems-- Most are made as open center-- Oil flows through the system whenever the pump is running reservoir to pump to valve back to reservoir under a low pressure if any. Now move the valve the oil will be directed to the "work" and pressure will build as the load increases until the load is lifted, if the load is too heavy or the end of the stoke is reached the oil has to go somewhere so the pressure increases until the relief valve opens. Without a relief valve something WILL break, pump, hose, valve etc. Remember the open center system uses a positive displacement pump. These systems are usually always self "bleeding".

Now for a closed center system This system uses a variable displacement pump. Pressure is always maintained at a preset level when the pump is operating. This system is best understood as thinking of the plumbing in your home. It is always up to pressure but has no flow. Open a valve the pressure drops slightly but fluid now flows, If the pressure drops enough the pump now starts pumping until the preset pressure is reached whether the valve closes, the load reaches the end of travel, or the load is too much to move. It is recommended these systems be bled if something has been repaired in the system, trapped air can destroy this system.
Why open or closed systems? Open center uses a set horsepower to operate it all the time but is cheaper to build. A closed center system uses power when it is pumping but frees up power when it is "shut down" or better said pumping very little, it also costs more to build it is usually found on higher priced equipment.

Hope this helps some of you understand hydraulic system and takes the mystery away.

Have a wonderful day and a better tomorrow

 

[AWSubie]

Just for those who are inexperienced with Hydraulics.

Excellent summary, Sir!