# Cat 252B machine gun



## NICHOLS LANDSCA (Sep 15, 2007)

On Friday out of the blue My 252 started to act up. What first caught my attention was after I dumped the bucket I went to lower the arms and curl the bucket all at once. IT went into slow motion ?? I backed up and went into the pile and tried to curl the bucket it moved a little and made a clunk/pop and stopped I moved the stick agian and it curled back. After playing with it here is what I found, it still is doing the slow mo thing, if you dead head the hyd. normally you just hear it stall now it sounds like a machine gun weather it's curling the bucket or lifting the arms all the way up or rolling the switch for the aux. hyd. (as if you had an attachment on) it sounds like a machine gun. Like it's bleeding off the pressure. It doesn't do it for the power attach or the drives. A main pressure relief gone bad? Called Cat dealer to ask ?? they said to bring it in, never heard of that before BS. Anyone had this happen?


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## powerjoke (Nov 13, 2004)

if i had to guess....and that's all it is.

it's got fluid in it right? 

it sounds as if the variable displacement pump took a crap on you. 

or maybe a colapsed filter?.........i'll ask a buddy that works at CaT if he's ever herd of it. i am sure it's happened before

PJ


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## Pirsch (Jun 1, 2007)

I'm not into the heavy equipment but used to use hydralic tools to cut things apart. Dirt in the Fluid causing the valve to stick closed letting the axl pump kick just so your not hung up and can't move? I'm just guessing but I like what PJ said... pump could have crapped out on you!

I've had the "Jaws O' Life" do that when I'm ripping a car door off. Dirt in the line. Just gave me enough power to close it down. Luckly had a sales truck for that kind of tool drive by. Took his stuff off his truck and used it and he fixed it w/o charge! Just had to pay him for the fluid.


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## Zodiac (Jul 9, 2008)

I've heard pumps make that noise before.

Sometimes it is the pressure relief too. 

Any fluid leaking anywhere?


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## NICHOLS LANDSCA (Sep 15, 2007)

No leaks, full of fluid, and it drives fine in low and high. Seems to be in the (lift circuit)? I will try a new filter in the morning just cause. Any help/ideas would be appreciated, I have no problem tearing into it just don't want to throw parts at it or take it in payup


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## Zodiac (Jul 9, 2008)

If you've got pressure gauges, you can test the pressure of the lift cylinders and see what they are at, it'll give you an idea if it's a pump or a valve.


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## NICHOLS LANDSCA (Sep 15, 2007)

I replaced the main relief valve $102 and about 2 min. to replace. All fixed.


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