2007 CAT 262C Bucket Curl function- bucket slowly uncurls - does not hold position

[Terminator]

Hello,

Greetings from the sunny Caribbean.

I have a nice 2007 CAT 262C (CAT0262CAMST00397) I bought online and just had delivered from the recent Ritchie auction and the bucket curl function has an issue: The bucket slowly uncurls- it does not hold its position at all. Loader arms are rock steady- only the bucket uncurls.

Machine has 5,000 hours and that is the only fault I find with it at this time.

Any ideas? - Seals? There is no outside hydraulic oil leak.

Thanks,

Bobby

 

[Huntoon]

debris in the lines?

 

[Terminator]

No. Hydraulic filters regularly changed. Also, loader arms operate and hold steady. All other hydraulic functions strong and ok.

 

[JDOFMEMI]

The most likely culprit is an internal leak in the bucket curl cylinders. Get 2 sets of seals and the problem will likely be solved. The curl cylinders take a lot of abuse. My 287 does the same under a heavy load, and I am preparing to do the same thing.

The second, and less likely culprit would be the valve, but it is not as likely, IMHO

 

[durallymax]

Repack cylinders.

 

[KSSS]

I had a similiar issue with a CASE machine once. It was a valving issue as I recall.

 

[Terminator]

Thanks for all the replies.

I ordered a CAT 262C Service Manual for this serial number machine but it will take a while to get down here. Does anyone have a page(s) from a service manual regarding the bucket curl cylinders and the seal replacement procedure/ steps? I would like to order the seal parts and have my crew do this repair ourselves.

Thanks

 

[Mjrdude1]

We have a Cat MTL that has this problem intermittently. We have isolated it down to a solenoid valve that is tied to the "Auto level" function. This function is an option on several Cat machines. You might check if yours is equipped... there is a rocker switch on the upper left side of the cab with a picture of a bucket and a couple of lines under it. We haven't repaired ours yet, as moving the switch to off and back on cures the drift issue. Just an idea of something to check before tearing down the cylinders.

 

[Terminator]

Fixed it!

Problem Fixed!

Had a good friend look at it.

Lifted up cab to look inside - saw new hydraulic pump- Hmmm...


Listened to hydraulic fluid hiss as it flowed through this valve block as the bucket uncurled.

Took apart the valve in the block and found the problem!



Broken spring inside valve. This damaged the actual valve block so that valve could not form a seal.



Bought new valve block, installed and Cat 262C working perfectly!



Seems somebody assembled the valve spring wrong, it sheared off during hydraulic operation, and particles of spring flew into hydraulic pump. We only found a small remaining piece of the broken spring still in the valve. Rest of it must have wreaked havoc with the hydraulic pump and that is why they replaced it.

Lucky they replaced it and I did not have to replace the hydraulic pump.

Also, found a valve spring on the floor of the undercarriage when the cab was lifted up. This spring was intact and we found it was missing from yet another valve in the block.

 

[SVTSHELBYGT500]

Just Had Same Problem On A 279C . Self Leveling Valve The Problem . Machine Had Approx. 1100 Hrs. Repaired By Cat Dealer .

 

[Terminator]

We changed the hydraulic filter after doing this repair. Although with the new hydraulic pump someone had put on, I assume the broken spring had already flowed around inside and did its damage to the hydraulic system with the filter catching what bits were left.

I do not know who did the initial repair (replacing the hydraulic pump) but I wonder why they did not find the source of the problem. That valve block is very close to the hydraulic pump. You can hear the 'Whooshing' sound of hydraulic fluid leaking past the valve as the bucket uncurls when you have the cab up and your ear close to the valve block.

Scary that when we found the original cause of the problem in the valve block, we still found that small broken bit of spring inside (see above pictures). Glad that small remaining piece did not shift and flow through the machine as we were operating the machine when we first bought it from Ritchie. It had the bucket uncurl problem from the very start when it arrived and we were operating it to check all systems.

 

[spatterfree]

is that while machine is stopped? i noticed our 262c is slowly tilting forward from day one on, can hear the increments as it's working it's way down, deere did the same thing, but this is a cat,
just wondering if it's normal.

 

[kuangqy]

I had a similiar issue with my machine too, change the self leveling valve was fixed.