Quick answer: Keep a bag closer running by oiling it on schedule (four pumps before starting and every four hours on the Model F; the NP-7A has an automatic oil pump; the Model 100 and Model 101 need oil and filter changes every 500 working hours), keeping it free of dust, replacing dull needles and knives, and letting the machine feed the bag. The manuals warn that pulling or holding the bag is a common cause of poor stitch quality.
Bag closers are simple machines, and most downtime comes from a few preventable problems. This guide pulls the maintenance and troubleshooting advice from our bag closer manuals into one place. Always follow the manual for your specific machine.
Daily checklist for any bag closer
- Check for loose fasteners.
- Check lubrication: oil reservoir full (handheld) or oil level in the window and no leaking seals (pedestal heads).
- Make sure the thread is properly threaded and chained off.
- Clear dust and debris.
- Keep optical sensors clean on pedestal heads.
- Run a couple of test bags before production.
Lubrication by machine
| Machine | Lubrication | Schedule (from the manual or product page) |
|---|---|---|
| NP-7A | Automatic oil pump | Keep the system supplied per the manual |
| Model F | Manual oiling (oil pump) | 4 pumps before operation; oil every 4 hours of operation |
| Model 100 | Self-lubricating | Check oil level before startup; change oil and filter every 500 working hours |
| Empress Model 101 | Patented pressurized self-lubricating system | Check oil level before startup; change oil and filter every 500 working hours |
Use the oil your manual specifies. The Model 100/101 manual warns that substitute oils void the warranty.
Weekly and periodic maintenance
- Model F, weekly: clean the machine in the recommended cleaning solution, as described in the manual.
- Model F, every 100 hours: check the motor brushes and replace them if shorter than ¼ inch (6 mm).
- Pedestal heads, daily: clean with compressed air through an OSHA-approved nozzle or a vacuum, manually lubricate knife blades and presser foot hinges, and check for loose fasteners.
Troubleshooting common problems
| Problem | Likely cause | Fix |
|---|---|---|
| Skipped stitches | Pulling or holding the bag; needle off-center in the guard; dull feed dogs | Let the machine feed; check needle alignment; replace worn feed dogs |
| Thread breaks | Wrong tension; bent or dull needle; threading error | Adjust tension in small steps and test; replace needle; rethread |
| Chain won't start; needle breaks after threading | Chain not started after threading | Model F: turn the pulley by hand clockwise through at least three complete cycles |
| Thread looks torn, not cut | Dull thread knife | Replace knife blades |
| Motor upkeep (Model F) | Brush wear | Check brushes every 100 hours; replace if shorter than ¼" (6 mm) |
Safety every time
- Wear proper eye, hand and foot protection, and tie back long hair.
- Turn off and lock out power and air before maintenance.
- Let the machine do the work. Don't pull the bag.
- The Model F is not suitable for areas where explosive materials are present.
Where to find your manual
Manuals for our bag closers are available to download on each product page: NP-7A, Model F, Model 100 and Empress Model 101.
Frequently asked questions
How often should I oil a portable bag closer?
It depends on the machine. The Model F manual says to press the oil pump four times before operation and apply oil from the pump every four hours of operation. The NP-7A has an automatic oil pump lubrication system.
How often do I change the oil in a pedestal sewing head?
The Model 100/101 manual calls for replacing the oil and the oil filter every 500 working hours, and checking the oil level and seals before startup.
Why is my bag closer skipping stitches?
The most common cause is interfering with the feed: pulling the bag through, holding back the bag or machine, or pulling up on the machine. Let the machine feed itself. Also check needle alignment and replace dull feed dog teeth.
Why does my bag closer thread keep breaking?
Check thread tension first, because improper tension will cause the thread to tear. Then check for a bent or dull needle and make sure the thread is properly threaded through the machine.
Why won't my bag closer start a chain after threading?
On the Model F, after threading, turn the pulley by hand clockwise so the sewn bag moves forward through at least three complete cycles. If you skip this step, the chain won't start and the machine may break the needle.
Should I use generic needles and oil in my bag closer?
Follow your manual. The Model F and Model 100/101 manuals call for the manufacturer's genuine needles, oil and spare parts, and warn that other oils or parts can void the warranty.
How do I clean a bag sewing machine?
Keep it free of dust every day. The Model 100/101 manual says to clean with compressed air through an OSHA-approved air nozzle or with a vacuum. The Model F manual adds a weekly cleaning in the recommended cleaning solution. Always turn off and lock out power and air first.
Need parts or help with your closer?
Tell us your bag material, product and how many bags you close a day, and we'll recommend the right closer. Call 866-888-6327 (Mon–Fri, 8am–5pm CST), email sales@clevelandequipment.com, or browse all bag sewers.