Ford 550 Backhoe Hydraulic noise.

[RamblerRebel]

I have a 1976 Ford 550 Backhoe Loader that has noise somewhere in hydraulic system. All hydraulics are working fine, but at certain RPM ranges noise comes from under the rear main control valve area. This noise occurs when speeding up or slowing down. It gets quite loud with movement of loader in conjunction with movement of machine. For instance, raising or lowering loader while pushing at the same time. Also noisiest while raising/tilting or dumping and moving at the same time. Like the more hydraulic pressure put on some valve or valves someplace makes it rattle or vibrate. I can minimize the rattling by lifting /tilting at idle and while not increasing engine speed or machine movement. No noise comes from front hydraulic pump. Hope someone has knowledge of the Ford 550 hydraulic system and can give me an idea of what the problem may be.

 

[Tom in Mo.]

Your flow from the pump first travels to the rear in steel tubing to feed the hoe control valve assembly before heading back forward to the loader control valve so all that flow when you use your loader is chattering back there someplace. My first check would be the pipe or hoses rubbing/vibrating against something else under the hoe deck. Simple things first. Inspection will be simpler with a hoe/tractor split which is not difficult. If the chattering turns out to come from the hoe control valve body then it's time to get the Service Manual for troubleshooting/servicing the hoe control valve body.

 

[RamblerRebel]

Thank you for the reply, but the "chattering" is not steel lines banging together. That would be a noise that could be pinpointed and distinguishable. The "chattering" occurs with multiple uses of tilt/raise/pushing and in unison with movement as well. A pipe would occur in on generalized location as well. This seems to travel from back valve body to tilt/loader valve. Sometimes I can feel it in the loader control lever. I have looked at and around hoses and lines looking for a clue but nothing seemed unusual. My suspicion is that it is some where in valve body as you suggest as well. Thank you for the time and advice..

 

[Tom in Mo.]

There is a anti cavitation relief valve on your loader control valve that may be suspect and backfeeding vibration thru the system. Note: i am not an expert, but I do own a 550 so I just surfed thru my service manual to see what I could find.

 

[RamblerRebel]

There is a anti cavitation relief valve on your loader control valve that may be suspect and backfeeding vibration thru the system. Note: i am not an expert, but I do own a 550 so I just surfed thru my service manual to see what I could find.

Yes, I saw that as well and have suspicions about the relief valve too. Wondering how hard it would be to service it and what if anything could be done. I think there is a relief valve on the main valve body If I am not mistaken. Thanks again.