Generac 4700 / QuietPact 40 — Crankcase Breather Inspection
Maintenance
For the Generac 4700 / QuietPact 40, from the Generac service manual.
Applies to: Generac 4700, Generac QuietPact 40, Generac GH-220 engine
Procedure
- Remove the breather tube. Check tube for cracks, hardening or other damage; replace if necessary.
- Clean the rocker arm cover in commercial solvent.
- Make sure the two small drain holes are open; use a length of wire if necessary.
- Check the rivets that retain the check valve, make sure they are tight.
- Seal all holes on the breather plate.
- Apply air pressure of 5 psi (0.352 kg/cm2) through the breather hose hole; no leakage must be observed.
- If necessary, reseal the plate with Type 103 black RTV sealant.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Air pressure 5 psi (0.352 kg/cm2)
- Type 103 black RTV sealant
Full service-parts list: Generac 4700 →, Generac QuietPact 40 →
Source: Generac service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.