743... how hard is this hose to change?

[62Clyde]

I recently got this 743 and knew it would need some repairs. 1st hard work and it sprayed fluid under the seat. This hose looks easy toward the front but gets tight with others toward the back, under the frame and not sure. Trying to decide to try mobile mech or tackle it.
I'm mechanical and work on my old chevy. New to hydrolic stuff. What tools needed? Oh and how does the air get purged?
Thanks.

 

[mrbb]

first off I'm NO expert here,and
I have never replaced that exact hose on your exact model, But it looks like both ends are not that bad to get at, might be tricky some what pending wrench/'s you have, but looks do able to me
if you wanted you can get some caps and plugs to help lessen the mess as fluid drains out of hose, but there not needed, some will drain no matter what you do!
as for air in system, things should self relief as you use the machine, just top system off before starting and check after running some and gravity should bled air out as things cycle thru system


some food for thought thought, is, I would first start with a good de-greaser soaking and mild power wash, as its always nicer to work on a clean machine when possible
plus, it will remove a lot of old grease, and be less of a fire hazard! dirt debris will be less likely to build up not having all that old fluids to stick too

and last the very top hose seems to be in worse condition, I'd be thinking about replacing that one
as it seems to be peeling apart on you!

 

[laurencen]

never replaced this hose on our 243s but what you need first is a good cleaning, way easier to work on and then get a assortment of wrenches you do not need, I found many times a specific wrench bent or welded was needed in some of these spaces, we have quite a collection of these and seems every time we use them its a game changer, also note check other hoses, just because this is the only one leaking does not mean others were not or close to leaking, when you are in there check other hoses for cracks or missing rubber on the outside, easy to replace today, next time you may be on a worksite, nt fun fixing anything away from the workshop

 

[Dave1234]

I have the same hose seeping. Can you keep us posted on what you encounter? I need to get to mine once the weather gets reliable to work outside. Like you, I lack Hyd experience. You at least need a set of crow's foot wrenches, if possible made for tubing fittings rather than standard open end ones. In my so far limited experience, nearly everything is hard to get at. This looks like one of the easier ones. Expect every hose to be hard as rocks and near impossible to flex. I have come to the conclusion they are essentially all worth replacing for that reason alone, but wish I had a list of all hoses with dimensions so I could buy at a better price.

 

[FJRDarksider]

Agreed on the cost of hoses. I took what I needed to replace over to Princess Auto (Ontario) and they custom cut it to match the length/fittings at a fraction of the cost Bobcat charges.

 

[62Clyde]

Yes.. will update. Got a 40 mph wind and dusty today... so a no go on even trying it today. Gona get some degreaser and spay it down atleast.

 

[Markle]

These wrenches help with tight spots also. Also crows foot like Dave said. Your motivation-save shop labor $$$-take pride you did it yourself.
I did a hose on the 873, and only one of the stubby wrenches would fit. Nothing else.

 

[oiu789]

Take some string or wire and lay out in the machine where the hose is routed before pulling the hose out. This way the new one will be put back in the same way the old one came out. So that there will not be any rubbing issues with. On longer ones tie the wire or string to the old hose before pulling it then tie the new hose to the string or wire to pull the new one in.

 

[laurencen]

Take some string or wire and lay out in the machine where the hose is routed before pulling the hose out. This way the new one will be put back in the same way the old one came out. So that there will not be any rubbing issues with. On longer ones tie the wire or string to the old hose before pulling it then tie the new hose to the string or wire to pull the new one in.

thats a good idea, having fighting with a hose on my bucket truck, took hours trying different routes

 

[ward]

Of a note when you look at the hoses the crimp on the fitting showes that hose has been replaced beforeas it has a bell shape where it meets the hose, the hoses lower and alongside the pump do not have a bell shape, the hose closer to the engine looks to be the make up oil hose coming from the hydraulic filter and looks to have cracks in it.
As far as replacing the hose it looks to be pretty straing forward, as I believe that you can reach to the right of the control linkage and underneath and access the fitting to the hose, the other end is going to go to a valve block I would expect down under the cover by your feet.

 

[62Clyde]

Of a note when you look at the hoses the crimp on the fitting showes that hose has been replaced beforeas it has a bell shape where it meets the hose, the hoses lower and alongside the pump do not have a bell shape, the hose closer to the engine looks to be the make up oil hose coming from the hydraulic filter and looks to have cracks in it.
As far as replacing the hose it looks to be pretty straing forward, as I believe that you can reach to the right of the control linkage and underneath and access the fitting to the hose, the other end is going to go to a valve block I would expect down under the cover by your feet.

Ward, when you say "make up" hose.. that mean like a low pressure supply?
Got the de- greasing done.. makes it look more doable for me cleaned up. see if I can get my wrenches on them tomorrow.. purchase more tools if not.
Thanks!

 

[ward]

Ward, when you say "make up" hose.. that mean like a low pressure supply?
Got the de- greasing done.. makes it look more doable for me cleaned up. see if I can get my wrenches on them tomorrow.. purchase more tools if not.
Thanks!

yes like about 300 psi when a hydrostat machine is running the drive motor and pump which run in a close loop have a case drain and the oil returning from the motors is alway a little less then what the pump sent, with out the make up oil you would end up with cavation which is a vacuum buble that inplodes and pulls metal atoms off the lens of the pump ( the lens looks like a bronze plate) and in short order this effect will ruin a pump, when I was working in Northern Virginia, and I was sent to a hydraulic class at Caterpillar and they had a pump assembly out of a 963 loader about a $16,000.00 pump per side at that time and the lens had been ruined in about 2 to 5 minutes due to lack of oil whild driving, the pumps left and right side were 96 gpm each running in a 18 gallon case a full blow hose would take seconds to empty the tank

 

[62Clyde]

Wow... thanks for the education!!

 

[rmshawgs]

N

Ward, when you say "make up" hose.. that mean like a low pressure supply?
Got the de- greasing done.. makes it look more doable for me cleaned up. see if I can get my wrenches on them tomorrow.. purchase more tools if not.
Thanks!

Not that difficult. Get some plastic caps (or metal caps from hyd shop) to plug the fittings when you remove the hose. Take hose to hyd shop and have it made. This is the high pressure hose from hyd pump to the control valve.

 

[62Clyde]

Well got it done today. Changed both hoses. Required tools: crowfoots open and flare, line wrench, std wrenches, magnet to fetch dropped tools.. lol. I followed the torque advice in the shop manual using a marker and amount of flats per size... if any leak will tighten them to good-n-tight. Test tomorrow. Changed the hydraulic filter while I needed to add fluid anyway.
Feels good to gain some confidence and do some hydraulics. Thanks for the help!!

 

[Tlawdogg]

Way to go!

 

[Markle]

Excellent!