How to Clean or Replace Bypass Poppet On A GPRO PRO20/PRO35 Pump

Replacing the poppet within a PRO20/PRO35 pump is straight forward. Here's how you can do it.


If you need to clean or replace the bypass poppet inside a GPRO PRO20/PRO35 Fuel Transfer Pump, watch the instructional video above or read the instructions below. Remember to wear properly fitting PPE when doing this task!

  1. Turn off the pump and disconnect from power
  2. Use a pipe wrench to unscrew the bypass plug, spring and bypass poppet from the pump
  3. Inspect the o-ring on the poppet (part numbers: 133505-01, 133505-04) for damage or wear
  4. If poppet components contain debris, wipe them clean with a clean cloth
  5. Before reassembling, remove the bypass plug o-ring and lightly coat with grease, then reinstall it back on the bypass plug
  6. Reinsert the bypass poppet, spring, and plug into the pump. Tighten in place



Offerings covered by this post:

GPI PRO20 115V Fuel Transfer Pump, 1″ Manual Nozzle, 18′ Hose & Tank Adapter Mount (20 GPM) – PRO20-115MD
GPI PRO20 115V Fuel Transfer Pump w/QM Meter (20 GPM) – PRO20-115PO/QM40G8N
GPI PRO20 115V Fuel Transfer Pump w/QM Meter, 18′ Hose & 1″ Auto Nozzle (20 GPM) – PRO20-115AD/QM40G8N
GPI PRO20 115V Fuel Transfer Pump, 1″ Auto Nozzle, 18′ Hose & Tank Adapter Mount (20 GPM) – PRO20-115AD
GPI 115V/230V PRO35-115AD Fuel Transfer Pump, 1″ Auto Nozzle & 18′ Hose (35 GPM) – PRO35-115AD
GPI 115V/230V PRO35-115 & QM40 Combo, No Nozzle (35 GPM) – PRO35-115PO/QM40G8N
GPI 115V/230V PRO35-115 & QM40 Combo w/1″ Automatic Nozzle (35 GPM) – PRO35-115AD/QM40G8N