Loader lifting very slowly

[WStringer2]

I have an L4740HST w/ an LA854 loader and the loader recently started lifting very slowly, regardless of engine RPM. It feels like something's out of whack with the control arm, but I can't be sure. It makes the soft hissing sound that it normally does when you're barely moving the control arm. I've visually inspected all hoses and don't see any leaks, and the hydraulic level is between the holes.

All other movements (curl, and down) work normally, and the box blade on the back raises and lowers at a normal speed. The tractor is about 5 years old, but only has 60 hours on it and according to the original owner has been treated well, lubed every 10 hours of loader use, etc.

Any ideas?

 

[Diydave]

I'd start by checking linkages and relief valve...

 

[Shadow]

Lower your 3pt arms slightly, does it work faster and the relief noise go away? More than likely, your 3pt top limit is out of adjustment. There's a rod on the back of the 3pt linkage that has 2 nuts on either side of a bracket that attaches to one of the lift arms. Takes 2 12mm wrenches, adjust those nuts until you have about 1/2" of freeplay, meaning that when the arms are in the topmost position, you should be able to manually pick up on them and get about another 1/2".

 

[WStringer2]

Lower your 3pt arms slightly, does it work faster and the relief noise go away? More than likely, your 3pt top limit is out of adjustment. There's a rod on the back of the 3pt linkage that has 2 nuts on either side of a bracket that attaches to one of the lift arms. Takes 2 12mm wrenches, adjust those nuts until you have about 1/2" of freeplay, meaning that when the arms are in the topmost position, you should be able to manually pick up on them and get about another 1/2".

Thanks Shadow...that was exactly the problem! I didn't notice before because I usually operate the rear hitch and bucket at higher RPM's, but when I lifted the box blade at a slow idle, I could hear the engine bog down when it hit the top limit.

 

[Shadow]

Not uncommon, glad you got it going.

 

[WStringer2]

Well, I spoke too soon! Turns out it worked fine for about an hour, then started getting slower and slower. After the 2nd hour it won't lift at all, even w/ the 3 point hitch totally down. I checked the fluid and it's not milky or foamy.

Any tips? Diydave mentioned checking the relief valve, any tips on how to do that on an L4740 Grand?

Thanks,

Walt

 

[North Idaho Wolfman]

First thing to do is swap the lines out of the valve to the loader so that tilt is lift and vice versa, that will tell you if it's the tractor or the loader.
if the problem swaps then it's in the tractor or valve, if it doesn't move you have a blow seal internally on the loader.

 

[WStringer2]

First thing to do is swap the lines out of the valve to the loader so that tilt is lift and vice versa, that will tell you if it's the tractor or the loader.
if the problem swaps then it's in the tractor or valve, if it doesn't move you have a blow seal internally on the loader.

That's a good idea, I'll give that a shot this afternoon.

It almost seems like the problem is at the control arm in the cab. When I pull back the arm to lift the bucket, it seems to have a very little play before the arm stops. Sometimes if I tap it back a few times it will "catch" and start to lift up slowly.

I'll swap the lines with curl to see if that works. If it does, is there a way to adjust the control arm?

Thanks for your help!

 

[North Idaho Wolfman]

With your last statement I'm thinking your problem is in the cable inkage, probably has come loose.

Depending on which exact model you have (HSTC or HSTC-3) it could be either set up:

HSTC

HSTC-3

 

[WStringer2]

Thanks Wolfman...I think you're right, I need to adjust the linkage; the control arm barely moves towards the back before hitting some sort of limit.

I have the HSTC-3, do you normally adjust at the control arm (near part # 140) or outside near part # 170/120? Actually, 170/120 don't appear to be the adjustment, but the 2 bolts to the left of 170/120 look like they could lengthen/shorten the assembly.

 

[WStringer2]

Thanks a lot for the diagrams, I started with the adjustment nuts on the outside because they were easier to get to, and that was all it took. I just needed to push it in a bit to center the control arm, and now it works like a champ!

One thing though, it doesn't feel as smooth going back as it does going forward. There aren't any grease fittings down there so I'm not sure there's anything I can do. Is that something I should be concerned about?

BTW - regarding the shop manual for the L4740, is Messick's $90 version my only option? Do you know if Messick's version is an original manual, or if it's just a photo-copy?

Thanks again for all your help!

 

[Tooljunkie]

Guess theres no way to get some lubricant on/in those cables?
Im sure something will help. A corroded cable will pull better than it pushes. It doesent take much for them to hang up.


So a little search gives me some generic information.
Remove swivel end off cable,find a foot of hose to slip over cable shield and clamp hose to shield. Now fill hose with a silicone based lubricant and push in a tire valve stem ground down to fit hose and clamp it. Apply no more than 50 psi air pressure until oil is seen leaking out other end. Clean up and reassemble.i know silicone base is preferred but i run with what i have.

This process is used in marine industry, about 3 oz lube for 20 feet cable. Juice of choice is marvel mystery lube. I would use sea foam up here.

Im editing this, as i just tried it. It will push lubricant down cable if there is no seals on the shield to cable. I just give the valve stem a little shot and let it sit. Went back a while and another shot of air. It did move lubricant down cable, but it was too far gone for lube to help.

 

[coachgeo]

Guess theres no way to get some lubricant on/in those cables?
Im sure something will help. A corroded cable will pull better than it pushes. It doesent take much for them to hang up.


So a little search gives me some generic information.
Remove swivel end off cable,find a foot of hose to slip over cable shield and clamp hose to shield. Now fill hose with a silicone based lubricant and push in a tire valve stem ground down to fit hose and clamp it. Apply no more than 50 psi air pressure until oil is seen leaking out other end. Clean up and reassemble.i know silicone base is preferred but i run with what i have.

This process is used in marine industry, about 3 oz lube for 20 feet cable. Juice of choice is marvel mystery lube. I would use sea foam up here.

THANK YOU. Never seen/heard of this before. You've earned yourself a place in form of a link in the ultimate READ ME.

 

[North Idaho Wolfman]

Regarding the shop manual for the L4740, is Messick's $90 version my only option? Do you know if Messick's version is an original manual, or if it's just a photo-copy?

It will be an original.

 

[WStringer2]

Thanks for the info guys, I really appreciate it!

 

[Rascal]

Guess theres no way to get some lubricant on/in those cables?
Im sure something will help. A corroded cable will pull better than it pushes. It doesent take much for them to hang up.


So a little search gives me some generic information.
Remove swivel end off cable,find a foot of hose to slip over cable shield and clamp hose to shield. Now fill hose with a silicone based lubricant and push in a tire valve stem ground down to fit hose and clamp it. Apply no more than 50 psi air pressure until oil is seen leaking out other end. Clean up and reassemble.i know silicone base is preferred but i run with what i have.

This process is used in marine industry, about 3 oz lube for 20 feet cable. Juice of choice is marvel mystery lube. I would use sea foam up here.

What a GREAT idea! !

 

[WStringer2]

Hey Guys,

I thought I'd give you an update on what I found out. On the 4740 the cable that connects isn't a braided cable, but more like a flexible rod. I did drip some 3in1 oil into the sheath as I worked the cable back and forth and that seemed to (eventually) penetrate the length of the rod and make the action a bit smoother, but it still felt like I was hitting some sort of invisible stop that was preventing the loader from lifting.

I wound up pulling the spool valves out expecting to see some corrosion or shavings, but it was clean as a whistle. The only thing I noticed was that one of the o-rings didn't appear to be seated properly. After seating the o-ring and putting it all back together, it works fine now.

Thanks again for everyone's help and advice!

 

[Tooljunkie]

Glad you got it solved. I ran a near new green one that uses cables. Not impressed at all. Could never landscape with it.
Tried to convince buddy to adjust/lube linkage and see if it improves. Nope,works fine for what i do.

Gonna have to borrow it again.and fix without his blessing.

 

[Clementine21]

L

THANK YOU. Never seen/heard of this before. You've earned yourself a place in form of a link in the ultimate READ ME.

Iused to have a cable pressure lube device for motor cycle which I used on mountain bikes. Loaned it out never got it back. Surely still available.

 

[Greg2]

L

Iused to have a cable pressure lube device for motor cycle which I used on mountain bikes. Loaned it out never got it back. Surely still available.

I was going to suggest the same item.