Hello, have a 721b with brake pressure light on. no 1st or 2nd gear forward or reverse caused by the light being on. 3rd and 4th work just fine. replaced switch on valve behind passenger rear tire, light blinks when unplugged. Machine has 18k hours on it. see it has test ports by valve, but would need to know the specs and where would a guy get the gauges and connectors for the quick connects? Any help would be greatly appreciated.
There is a brake accumulator valve will have to be rebuilt or replaced if you can find one. It is located in the frame behind the left rear wheel. There are two parker pressure gauge connectors inline. The valve is held on by two bolts that go through the valve to a welded mount. You also need to check your accumulator charge pressures.
i checked pressure at the accumulator valve both read 1150 at high idle, low idle was 950. so that means brake pump is weak correct? also pumped brakes down, took approx 10 pumps and the accumulator to get to 825 and than gauge went to 0. So i assume accumulator is working as it should be?
That means the accumulator charge valve need to be rebuilt or replaced. The valve gets its oil from main pump via the pressure reducing valve. You also need to check the nitrogen charge pressure in the accumulators. By the way what is the serial number of your machine?
JEE0055212
How do you check the accumulator? Where should i source the valve or rebuild kit at?
Ok the part number for the complete accumulator charge valve is 232532A1 I would do some research on line to see if you could find it aftermarket. Case wants over 1500 for it. There are two service kits to rebuild your valve though the part numbers for those are 232532A1 & 409474A1 good luck. You will need an accumulator charge kit to test pressure on accumulators and to recharge them unless you take them off and have them recharged at a shop. Probably wouldn’t be a bad idea to have them rebuilt as well.
A little update. Rebuilt valve with no fix, replaced valve and fixed it. Also replaced pump because front seal was leaking hydraulic oil into engine.