1996 case 1845c with m46 tandem drive pump. Pump is completely rebuilt and new drive motors as well. When you get into a load in forward and reverse the machine just sits and tires do not spin on either side and engine does not die down it just runs wide open as if . Is it possible that all 4 SCR VALVES are bad? What are some tests I can run? I've already checked the charge pressure and it is fine even when u put it into a load it is still up high.
Will it roll downhill with the bucket up and controls in neutral? If so the bypass valves are open, see pdf. Aside from that check pressures, may be set to a lower than factory setting.
There's 2? And how do you open and close them? If they are tight does that mean they are closed
One for each pump/drive circuit. Back them out three turns (NO more) to tow, *slowly* if you have a dead machine. Turn them in tight to seat the bypass valves. I do not know if that machine has parking brakes or not, that's just what the valves are built into the pumps for.
It has the pins that lock into the drive sprockets vIA cable connected to seat bar. I actually did check those and took them out and put them back in tight and still same issue
Ah, with that system you could actually tow the machine with the bypass valves open, if it had spring applied/hydraulic pressure release parking brakes you couldn't move it if the engine wasn't running.
I meant I checked the bypass valves and put them back in tight and still same issue. Sorry
Oh oops... then it's possible all four SCR valves are the wrong value, were they replaced or?
No they were never replaced when the pump was rebuilt and machine has 3400 hours. It's not odd for all 4 to go bad? They are 300 bar 4350psi. Is there a way to test these?
If all four failed simultaneously you should run out and buy a lottery ticket the odds are astronomical. The MA, MB, MC, MD ports are where you check the high loop pressures:
You might pop one of the plugs off the top of an SCR, make sure there's a spring in there, then the valve cartridge? Grasping at straws...
Some questions...... The pumps were "completely rebuilt" - did you pay someone to do this? - Any warranty?? Were the pumps bench tested? Are both motors brand new? or rebuilt? Why were the pumps "rebuilt"? What was the original fault? Was there a major failure? Was there large amounts of contamination present? Were the original loop hoses reused? If not, were ALL the hoses THOROUGHLY washed before they were refitted? Was the oil cooler flushed? Sorry, this info is required to diagnose such a situation.