Support the discharge manifold (3) and tap from the backside with a soft mallet to separate from the crankcase
and gradually work free from cylinders.
Pump models with the o-ring groove on the outside of the valve seat (4) require the assistance
of a reverse pliers to remove the valve seat.
Valve assemblies will remain in the manifold (3). The valve (5), spring (6), o-ring (7), back-up ring (8), and
retainer (9) will then fall out when the manifold (3) is inverted.
Pump models without the o-ring groove on the outside of the valve seat (4) permit the seat,
valve (5), spring (6), o-ring (7), backup ring (8) and retainer (9) all to fall out when manifold (3)
Replace retainers (9) in manifold chambers. Next insert spring (6) into center of retainer.
Inspect the valves (5) for wear, ridges or pitting and replace if necessary. Note: Seating side of flat valves may
be lapped on flat surface using 240 grit paper. Quiet valves due to their shape must be replaced.
Insert valve (5) over spring (6) with recessed (dish) side down.
Next examine the seating surface of the flat valve seats (4) and lap with 240 grit paper or replace if evidence of
excessive wear. Quiet valve seats should be replaced if worn. Lap new quiet valve and seat to assure positive
Examine o-rings (7) and back-up rings (8) and replace if worn. Always lubricate o-rings for ease of installation
and to avoid damaging elastomers.
First install o-ring (7) in groove on seat (4) (towards seating surface), then back-up ring (8).
Models without outer groove on seat require the o-ring to be placed on lip of retainer.
Insert valve seats (4) into manifold chambers. Position manifold (3) back onto pump.
Lubricate o-rings on cylinder and exercise caution when slipping manifold over cylinders to
avoid damaging cylinder o-rings.