BX 24 hissing from ram

[canbug]

Hi guys, I'm lucky enough to own a BX 24 with back hoe, it has 120hrs of varied use. Light use like cutting grass and some hard use like moving large rocks.
I was digging and moving dirt this weekend and about half way though the job I started to hear a hissing noise coming from one of the bucket lifting arm rams only when I was lowering the bucket. There was no loss of power and the noise only occured when lowering the bucket, loaded or empty.
I'm not worried about it yet but is there anything I should be looking at or for?

Thanks Tim.

 

[powerstroke444e]

Any oil leaks? If not you may just need to grease the pins? Or you may be using the float position and you can here the oil moving threw the valve. Also check to see if you crushed a line.

 

[canbug]

No leaks that I can see, I'll try the paper test. It only happens on the ram retracting. It sounds like air trying to enter the ram, not like that dry steel sqeeking sound, more of a hissing noise.

Tim.

 

[Armchair Ninja]

I just had the same thing start happening with one of the cylinders on my FEL. Not sure what's causing it. It is also only when lowering the loader.

 

[J_J]

If the cylinder has pressure, and seems to be working normally, then,

A remote possibility is that it might be air, but the system would be a little spongy, and if it can draw in air, with a vacuum, then it will leak. What may sound like air, just might be the wiper seals sliding on the cylinder rod. Put a little lubricant on the rod at the seal line and activate the cylinder to spread it out.

 

[soulasphil]

I had exactly the same problem on my JD 3520 after leaving the loader outside in the rain for several days. I still don't really understand what produces the hissing sound while the FEL works perfectly. I thought it was air in the lines as the FEL had been disconnected, but then it should have stopped rapidly. In fact the noise stopped completely after greasing the pins and oiling the cylinder rods.

 

[Skyco]

and if it can draw in air, with a vacuum, then it will leak.

Not sure if you mean it will leak air in or also leak fluid out.
Though uncommon I have seen one way leaks...depending on seal design it can seal one way but not the other!

 

[J_J]

Not sure if you mean it will leak air in or also leak fluid out.
Though uncommon I have seen one way leaks...depending on seal design it can seal one way but not the other!

I was just saying that if there is a way in, there might be a way out. The air would try and stay to the top of the cylinder, and if the air can't get out through the seals, then the fluid will expunge it through regular cylinder action.

I agree. There is another noise that is caused by a large volume of fluid being pushed through a small orifice, and this will generate bubbles, sounding similar to a relief valve going off.