Magnum Venus Plastech Powerhead MPH_VPH–4250 Series - Manual (Page 21)

MPH / VPH – 4250 Series Manual
Rev. 05/2012 Page | 21
Pilot Valve Rebuild:
NOTE: The two Pilot Valves in the Upper and Lower End Caps are the same.
1. Remove the Inlet Spring Housing (MPH-2541) from the Upper End Cap (VPH-
4255). Remove Spring (MPH-2533) with Inlet Rod (MPH-2540). Turn the End Cap
over and a small Spring (MPH-2526) will fall out. (See Figure 5)
2. Replace O-ring (O-B-012) on the Spring Housing (MPH-2541) and the O-ring (O-U-
006) on the Inlet Rod (MPH-2540). Coat O-rings and Springs with a light coat of
SUPERLUBE grease (SUPERLUBE). Set Spring (MPH-2533) into the Spring
Housing (MPH-2541) with Inlet Rod (MPH-2540) facing up.
Figure 5:
The MPH-2526 spring will be installed from the
bottom of the end cap.
NOTE: Do not install the small Spring (MPH-2526) at this time. Screw the Inlet
Spring Housing (MPH-2541) into the Upper End Cap.
3. Remove the Stem Seal (MPH-2511-01) from the bottom of the Upper End Cap.
Remove the Seal Guide (MPH-2512) with the Spring (MPH-2528). Replace O-ring
(O-B-012) and lightly coat O-ring and Stem with SUPERLUBE grease
(SUPERLUBE). Drop the small Spring (MPH-2526) into the stem seal bore, the
Spring should center itself onto the end of the Inlet Rod (MPH-2540). (See Figure 6)
MPH-2526 Spring