I have a 77 4500 tlb and just finished my first ditch project and have a puzzler. I suspect the pump has a problem but it doesn't look to easy to pull, so I thought I would ask for advice. My book cover 5500 hydraulics and it had the pump on the PTO. Any way all the controls work to a certain pressure and stop (bypassing) and the pumps is loud and vibrates. Front end loader, all the backhoe functions either against the stops or digging, stabilizers etc. Does the pump have a built in bypass? Any suggestions or info would be appreciated. thanx steve
hydrolic pump I have a 1973 4500 TLB, There is a screen filter in the bottom of the hydraulic reservoir, to get to it remove the front cover to get to the pump. there you will find a pipe w/a 4 bolt flange coming off the bottom of the reservoir and connecting to the hose that connects to the loader frame. to remove the oil from the reservoir remove the large cap on top next to the hydraulic dip stick and remove the filter. use a hand transfer pump and remove the oil to a clean 5 gal bucket. the reservoir holds 4 1/2 gals. using a 1 gal bucket remove the hose clamp and drain the remaining oil in the pipe flange. remove the 4 bolts & pull straight down on the pipe the screen may have an O ring securing it. if so remove the O ring and the screen filter can be removed . this is recommended every 500 hours. the gasket can be purchased at the ford dealer and the reservoir filter napa can order make sure to take the old filter with you cause there are several different sizes
Randy-Thanx for the info. Not that it matters much but mine is not a 77 but 71/72. I had a guy that knows a lot more about hydraulics than I do (not hard) look at it and he feels it might be in the backhoe valves, possibly system relief valve. He recommended changing the filter and cleaning the screen, and cutting the filter apart to look for metal. I may have to pull the hoe off but it doesn't look that hard, just dangerous. When he has some time he is going to put his gauges and it and check pressures.