Hard
1-2 hours
Piston Bumper 885289
OEM part for: Metabo HPT (Hitachi)
Part Number: 885289
$10.37
Usually ships in 7 - 12 business days
Leaves our warehouse within 7 - 12 business days
Compatibility
This part will fit the following 5 machines
Metabo HPT (Hitachi)
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This item works with the following types of products:
- Nailer Parts
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Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
Misfiring nail gain. It needed an overhaul.
Martyn - August 14, 2018
Tool Type
Nailer
Difficulty
Hard
Time
1-2 hours
Tools Used
Screwdriver, Pliers, Wrench Set, Allen keys, snap ring pliers, iPhone camera
Parts Used
1. Complete tear-down of the Hitachi gas nail gun cylinder assembly. The metallic cylinder assembly must be removed from the outer plastic casing. There are also two bright metallic guides that need to be removed before the two-part cylinder assembly can be separated. There are steel pins that locate those parts. Little teensy rubber O-rings retain the pins.
2. Removed the snap ring allowing the piston to be removed from cylinder
3. Removed and discarded the old piston bumper (it was in bad shape)
4. Cleaned all metallic parts with brake cleaner
5. Cleaned out the cylinder exhaust port and cleaned filter elements
6. Installed the new piston bumper
7. Lightly lubricated the cylinder with an approved gas nail gun oil (Pasload)
8. Lightly lubricated other sliding metal parts with the approved gas nail gun oil (Pasload)
9. Installed the cylinder carefully. Compressing the two rings was initially challenging. I ended up using 12 gauge copper electrical wire electrode and inserted those into the small recesses around the entry of the cylinder. I bent the wire pieces back over the edge of the cylinder housing to hold them in place and then inserted the piston. The wires acted as little ring squeezers (compressors) and allowed the piston to slide into the bore of the cylinder (this really deserves a picture). Make sure the rings gaps are opposite each other before installing the piston.
10. Re-install the snap ring
11. Then it was a matter of checking the piston was oriented correctly and could slide freely.
12. Reassembly - hard to detail here in this forum; there are at least 10 steps
13. The gun now works like new.
2. Removed the snap ring allowing the piston to be removed from cylinder
3. Removed and discarded the old piston bumper (it was in bad shape)
4. Cleaned all metallic parts with brake cleaner
5. Cleaned out the cylinder exhaust port and cleaned filter elements
6. Installed the new piston bumper
7. Lightly lubricated the cylinder with an approved gas nail gun oil (Pasload)
8. Lightly lubricated other sliding metal parts with the approved gas nail gun oil (Pasload)
9. Installed the cylinder carefully. Compressing the two rings was initially challenging. I ended up using 12 gauge copper electrical wire electrode and inserted those into the small recesses around the entry of the cylinder. I bent the wire pieces back over the edge of the cylinder housing to hold them in place and then inserted the piston. The wires acted as little ring squeezers (compressors) and allowed the piston to slide into the bore of the cylinder (this really deserves a picture). Make sure the rings gaps are opposite each other before installing the piston.
10. Re-install the snap ring
11. Then it was a matter of checking the piston was oriented correctly and could slide freely.
12. Reassembly - hard to detail here in this forum; there are at least 10 steps
13. The gun now works like new.
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Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
Based on data from past customer purchasing behaviors, these parts are most commonly purchased together along with the part you are viewing. These parts may be necessary or helpful to replace to complete your current repair.
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