With all the glass in our articulated I noted a hydraulic whine much like when a power steering pump is running low. Very annoying and not something I had noticed earlier. Outside the cab not so bad but very loud inside.
Dawned on me it might be from closing the cab in with the glass, good clue was when you shut the door it got much worse. Th only thing the hydraulic pump runs at this time is the steering. From the pump the fluid goes to a priority valve which allocates the first 4 gallons to the steering the rest going back to the reservoir.
This cast iron valve is bolted to the back of the cab with a couple 1/4 inch bolts. unbolting the valve and letting it hang resolved the issue short term.
Last night I built a bracket for the valve then bolted the bracket up to the cab via four rubber isolators. Worked much better then I could have hoped for. Guess the cab was acting as a sounding board. Odd as the valve was bolted to a pretty stout three by three x 3/16 square tubing which an integral part of the cab frame.
Dawned on me it might be from closing the cab in with the glass, good clue was when you shut the door it got much worse. Th only thing the hydraulic pump runs at this time is the steering. From the pump the fluid goes to a priority valve which allocates the first 4 gallons to the steering the rest going back to the reservoir.
This cast iron valve is bolted to the back of the cab with a couple 1/4 inch bolts. unbolting the valve and letting it hang resolved the issue short term.
Last night I built a bracket for the valve then bolted the bracket up to the cab via four rubber isolators. Worked much better then I could have hoped for. Guess the cab was acting as a sounding board. Odd as the valve was bolted to a pretty stout three by three x 3/16 square tubing which an integral part of the cab frame.