Sundstrand 15 Series Inline Hydraulic Pump
When you don’t need the relief valve parts (8,9,10,11 & 12), these are being changed with the charge relief valve parts (23,24,25,26 & 27. Now the port where the charge relief valve parts use to go is abetted.
Now you will need to take off the plug #23, take out the spring #26 and poppet #27 out of the housing part. There will be no need to mess with the shims #25 or switch out parts that go to another valve. Look over the poppet and make sure it is down in the housing to take away any debris that is in the valve. If you need to replace parts and put them back in the housing unit.
If you want to put in the relief valve you need to take out the plug #12 then push in the spring #9 & poppet #8 out of the housing. There is no need to mess with the shims #25 or try to get parts from another valve and try to put them on this one, will not work correctly. And keep your eye out for debris getting in the valve space.
To do the acceleration valves take out plugs #20 from both sides of the housing and push out one valve assy. #22 and spring #16 from either side or the other valve assemblies #22. Always look over your parts before putting them back into the housing or if you need to replace your parts do that before you close up your housing.