Echo MS-53BPE, Use And Care Manual

9E

5) Remove the three bolts attaching the piston cylinder to the bottom of 
the tank (Figure 4).

 6) Reach in through the tank fill opening and remove the piston cylinder.

7) Remove check valve cartridge assembly from bottom of piston cylinder 
utilizing pump handle clip (clip has flat blade incorporated into end).  Place 
flat blade into slot in bottom of cartridge and unscrew (Figure 5 and 6).

8) Once cartridge has been removed it can either be replaced as an 
assembly or rebuilt.

9) To rebuild disassemble two halves of cartridge and replace seal and/
or ball. Replace cartridge (Figure 7). The seal mounts inside the larger of 
the two halves of the cartridge. The seal counterbore side mounts into the 
grooves in the cartridge halve. Pump performance my be affected if this is 
not assembled correctly.

10) At this point the piston cylinder itself and/or piston cylinder stud 
gaskets can be replaced. The piston cylinder stud gaskets must be oriented 
correctly or leakage may result (Figure 8).

11) Reassemble piston cylinder using washers and bolts on the underside of 
the base.

12) Replace pump assembly into tank and into the piston cylinder which is 
mounted on the bottom of the tank (see important notes regarding gasket 
and felt washer in Pump and Disassembly and Rebuild section). Be careful 
not to damage the plunger seal as it seats into the piston cylinder. It is 
recommended that you  look through the tank fill opening while performing 
this to achieve better alignment.  If necessary you can also reach in and use 
your hand to guide the plunger seal into the piston cylinder.

13) Position the pump outlet (hose connection) in the desired position. 
Tighten the pump retaining ring onto the tank. 

14) Reach into tank fill opening and attach agitator to pressure chamber 
body.

15) Connect linkage arm to the top of the pump assembly (see section 
covering Installing the Pump Handle)

Figure 5

Piston Cylinder

Figure 4

Check Valve

Flat side

Seal

Ball

Counterbore Side

Figure 6

Figure 7

Stud Gaskets

Figure 8