Loader Left side of loader not lifting

[Thumper1]

Hello,

I'm new to tractoring so please forgive my ignorance, at least for a month or so.

I'm using a JD 4500 with a 460 loader, the left side of the loader dosn't seem to want to lift, like it's weak.

I re-built the lift cylinder trying to correct this problem, however, that didn't help. The good thing is I can add cylinder re-building to my list of can do's.

I was going to look at the control unit next but the thing is, even though I know what I'm looking at, I really don't know what I'm looking for. There are no leaks in the system, and it doesn't sound like there is a restrection in the line.

Truth is I need some help

Thank you in advance

Thumper1

 

[kennyd]

Welcome to TBN

I can't see the valve being a problem if the other side is lifting fine as you say-that only leaves the cylinder. I would recomend swapping the cylinders from side to side to see if anything changes. There are ways to test the cylinder also. Could one of the hydraulic tubes that cross the loader torque tube be crushed?

 

[Thumper1]

I'll give swapping the cylinders a try, I didn't see any crushed lines, however, two of them have been replaced, I know this because they don't have any green paint on them and the others do.

I'll look around for crushed lines and swap cylinders and post the results results.

 

[B8FISH]

I'd also look at those two replaced lines--maybe even take them off, clean up the threads etc and re-connect. Make sure they are sized correctly (were they sourced via JD from the prior owner??). It doesn't take much (a little teflon tape??) to slow things down.

 

[Thumper1]

Thanks B8,

I worked my butt off today, I didn't have time to even look at the tractor, let alone as my wife would say "play with it". Where do they get that stuff anyway? I'm using the tractor to landscape and build her flower beds but if I have to work on it, I'm playing with it.

I'll give the lines a shot, I noticed when I lift the bucket, the left cylinder bounces a bit, not a lot just a few mm or so, I've always thought it had a air lock but I can't find where it would be locked up at.

Thumper1

 

[KWentling]

After you put the cylinder back on, did you stroke it completely both ways and hold it against the relief to push all the air out? If not, you probably do have air in it.

Kim

 

[Barely Smokin']

x2 on swapping the cylinders to see if that isolates the problem. That should tell you a whole lot. Also, x2 on stroking the cylinder back and forth to the limit a few times and make sure your hyd fluid is topped off.

If you find that it's not the cylinder, I'd start by visually inspecting the fittings in the suspect circuit. I had a similar problem on my backhoe, which I traced down to a fitting that, instead of having a 3/8" opening in it, had a 1/16" hole in it. Big difference! You couldn't tell the difference from the outward appearance of the fitting. It was either a flow-restricting fitting or a manufacturing defect. I switched it out and voila! fixed.

Also, maybe check how evenly the cylinders stroke when one end of each is not connected. You could possibly be seeing some kind of bind in your loader.

 

[Thumper1]

Thanks for all you're help so far, wanted to get that out of the way so I don't forget.

No I didn't stroke the cylinder, I'm not sure I really know how to do that without running the other cylinder. Do I unhook both cylinders from the loader and work them that way? or do you mean for me to run the loader up as far as it goes then back down a couple of times? I'm trying not to be a complete moron here, I just don't know. I work on equipment and machines for a living, just not this type.

Thumper1

 

[KWentling]

Thumper; Just run the loader all the way up until it tops out and hold the lever until you hear the pressure relief open (will be kind of a squealing sound and the engine will load up), and then do the same lowering it. Do it a couple of times each way. That will push all the air out of the system and you won't hurt a thing. See if that doesn't cure you're problem.

Kim

 

[RoyJackson]

Thumper; Just run the loader all the way up until it tops out and hold the lever until you hear the pressure relief open (will be kind of a squealing sound and the engine will load up), and then do the same lowering it. Do it a couple of times each way. That will push all the air out of the system and you won't hurt a thing. See if that doesn't cure you're problem.

Kim

Good idea and this is the first thing to try. If this doesn't work, and Thumper doesn't find any kinked or crushed lines (don't forget to check out the hoses, Thumper...one or more may be deteriorating), then Kennyd's idea of swapping the cylinders is next.

Thumper, I'm pretty late to this thread..but when did you notice this problem? Was it from day 1 of ownership? Was it after a particular type of loader work?