Hello new to the site looking for some help. I have a diesel 71 or 72 JD 310 backhoe a recently purchased. The brakes are very spongy and do not hold. I know where to find the bleeders but not where to add the fluid during the bleeding process. I am not sure what type of fluid to add. I did not see that information in my manual. Also front loader bucket movement seems to labor the engine more than the digging end. It can easily stall the engine if the RPM is not above 1200 moving the front loader.. Any help will be appreciated
Some backhoes are set up so the brake master cylinders are supplied with fluid from the main hydraulic fluid return system- like my old IH 250A.
Early JD 310 I have the same machine...the hydraulic fluid sump/reservoir in the transmission is drawn by the braking system to operate the brakes. I would suggest you change the transmission and hydraulic filters...when you pull the horizontal transmission filter on the right side under the frame, the housing is attached to the transmission sump/reservoir with a 3/4" hose about 2-3" long. Behind the short hose, inside the transmission is a long filter screen that could be sludged up...I live in CT, where are you located?