LockNLube Grease Coupler (Standard 1/8″) – (GC81011-NPT/GC81068-NPT) / (GC81011-BSPT/GC81068-BSPT) - Troubleshooting
The original, patented LockNLube® Grease Coupler, a quick-connect grease gun coupler that locks onto grease fittings (zerks) and stays on without leaking up to 10,000 PSI. With a thumb lever, it releases instantly even under pressure, ending the common frustrations of greasing (couplers popping off, messy spurts, stuck couplers). Fits all standard grease guns via 1/8″ connection and is fully rebuildable.
- Attaching the Coupler
- Press thumb lever fully to open jaws
- Push coupler fully over the grease fitting
- Release lever to lock; slight click or feel indicates engagement
- Tug gently to confirm it is locked
- During Greasing
- Pump grease normally once locked
- If grease leaks from the sides:
- Fitting may be completely clogged (use Grease Buster)
- Or coupler may not be fully seated—reattach properly
- Detaching the Coupler
- Press thumb lever and pull off
- Small hiss during release is normal pressure bleed‑off
- If stuck, press lever firmly and wiggle gently
- Do not yank without releasing the lever
- Compatibility Checks
- Designed for standard Zerks (~0.390″ head diameter)
- Clean heavy paint or rust from fittings if needed
- Button‑head or flush fittings require different adapters
- Routine Maintenance
- Wipe jaws clean to prevent abrasive wear
- Periodically apply light oil to jaw mechanism
- Avoid impacts that could bend the lever or misalign jaws
- Leakage or Weak Grip Over Time
- Indicates worn internal seal or jaws
- Rebuild using a coupler rebuild kit
- Pressure Management
- Coupler can be released under pressure
- For electric or pneumatic guns, relieving hose pressure first improves cleanliness
- Installation Notes
- Fits grease gun hoses with 1/8″ threads
- Use thread tape or sealant during installation
- Summary
- Minimal maintenance required
- Keep clean, lightly lubricated, and rebuild when wear appears