Perkins — Closed circuit breather (naturally aspirated) - to clean and to renew
Maintenance · Breather system
From a Perkins service manual covering: 403C-11, 403C-15, 404C-22. Check it applies to your exact model before use.
Applies to: Perkins 403C-11, Perkins 403C-15, Perkins 404C-22
Before you start
- Ensure components are fitted in their correct position; incorrect fitting may damage the engine.
- It is important that the area around the vent hole is clean.
Procedure
- Release the four setscrews and remove the breather cover, the spring and the diaphragm assembly.
- Clean the breather cavity in the rocker cover.
- Clean the breather in clean diesel fuel.
- Fit the breather assembly into the cavity in the rocker cover, ensuring the breather cover, diaphragm and spring are assembled correctly and the vent hole faces towards the flywheel.
- Tighten the four setscrews.
Specs & values
- The breather assembly should be renewed every 2000 hours.
Full service-parts list: Perkins 403C-11 →, Perkins 403C-15 →, Perkins 404C-22 →
Source: Perkins 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.