LockNLube Pistol-Grip Grease Guns – Heavy Duty & Premium Models (LNL153-450 & LNL252-450) - Troubleshooting
High-quality one-hand operated pistol-grip grease guns designed for reliable, leak-free greasing. The Heavy Duty model (LNL153) features a rugged steel/cast head and outputs up to 5,000 PSI, while the Premium model (LNL252) has a lighter cast aluminum head and can deliver up to 8,000 PSI for the toughest fittings. Both guns include the LockNLube® Grease Coupler, a 20″ high-pressure hose with in-line swivel, an air bleeder valve, and a Loop & Lock™ handle clip for clean storage.
- Loading & Priming
- Pull follower rod fully back and insert grease cartridge
- Thread barrel partially, release follower, then bleed air
- Use bleeder valve or slightly loosen barrel while pumping
- Tighten fully once grease flows
- Air Lock Issues
- If pumping produces no grease, bleed air while pumping
- Premium model primes especially easily due to follower design
- During Use
- Take breaks during extended greasing to reduce hand fatigue
- Avoid forcing grease into fittings that are completely blocked
- Use clog‑clearing tools if necessary
- Hose & Coupler Checks
- Inspect hose for cracks or bulges
- Ensure coupler is fully locked on the fitting
- Tighten hose and coupler connections periodically
- Coupler Wear
- Signs include grease leakage at tip or harder release
- Coupler is rebuildable with inexpensive seal/jaw kits
- Cleaning & Storage
- Wipe coupler before and after use
- Use Loop & Lock to store hose neatly
- Store in a clean, dry place
- Avoid leaving follower fully compressed when stored empty
- Bulk Filling
- Both models support suction fill
- Use bleeder valve to remove air afterward
- Model‑Specific Notes
- LNL252: Stop pumping when handle becomes very hard; do not use cheater bars
- LNL153: Ensure follower rod is properly latched to prevent grease bypass
- Summary
- Minimal routine maintenance required
- Keep clean, properly primed, and inspect wear parts periodically