Allmand — Check Valve Blocked Flow Repair
Repair & overhaul
From a Allmand service manual covering: M-250 Series, M-258, M-259, M-301, M-303, M-304, M-310, M-311, M-313, M-314, M-319, M-326…. Check it applies to your exact model before use.
Procedure
- Remove check valve components and replace the spring.
- If problem persists, replace ball type with poppet type as they cannot completely block flow.
- Adjust screw to proper depth.
Source: Allmand 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.