Allmand — Adjustable Needle Valve 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.
Before you start
- Do not jam needle on seat or permanent damage could result.
Procedure
- Open needle by loosening jam nut on stem and turn stem out.
- Inspect for dirt in ports and remove if possible.
- Blow compressed air through valve.
- Turn needle to full closed position (do not jam on seat).
- Blow compressed air into one port and check if blocked from exiting other; replace if dirt cannot be removed.
Tools required
- Compressed air Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
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.