Easy
30-60 minutes
This is a genuine part assembled by original manufacturer. It is compatible with various Hitachi nailers. An o-ring is a simple yet essential piece which seals connection points, preventing leaks and protecting joints. Each tool may use more than one size of o-ring. For proper performance, be sure the correct o-ring is being used. Sold individually.
Piston O-ring 884958
OEM part for: Metabo HPT (Hitachi)
Part Number: 884958
$4.99
In Stock
Ships within 1 business day 
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Frequently Purchased Together ?
Compatibility
This part will fit the following 13 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.
Still wouldn't nail, after repairing trigger assembly.
Steve - October 2, 2020
Tool Type
Nailer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Screwdriver, 2-Allen wrenches
Opened cylinder, put new peices in place of the old ones, good or not. The valve rubber and exhaust valve rubber, were the original ones were deteriorated, put cylinder back together. Hooked up to air compressor, nailer did its job, nailed the nails again.
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Leaking air and would not fire not leaking air anymore, but still not firing
Jacob - February 13, 2019
Tool Type
Nailer
Difficulty
Easy
Time
1-2 hours
Tools Used
Socket set, Allen wrench
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Driver piston was loose in cylinder
Jason - August 23, 2018
Tool Type
Nailer
Difficulty
Easy
Time
Less than 15 minutes
Tools Used
, Allen wrench
Parts Used
1. Remove top cap from nailer
2. Remove driver piston
3. Replace o-ring and lubricate
4. Re install in reverse order
2. Remove driver piston
3. Replace o-ring and lubricate
4. Re install in reverse order
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Bumper broke and damage the piston o-ring
Roberto - August 6, 2018
Tool Type
Nailer
Difficulty
Easy
Time
30-60 minutes
Tools Used
, Allen wrench
Parts Used
Remove the front part of the nailer remove the remaining bumper pieces and clean the piston chamber and install the new parts
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Hitachi nailer piston failed
Mark - March 8, 2018
Tool Type
Nailer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Socket set, Wrench Set, Pliers
Remove the cylinder head, the cylinder bore and replace all parts in reverse order.
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Nail gun was leaking air
Robert - December 21, 2017
Tool Type
Nailer
Difficulty
Medium
Time
30-60 minutes
Tools Used
Screwdriver, Allen wrench
Replaced all parts that was ordered and when finished the nail gun worked great, will be able to use it on more roof jobs.
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Broken drivers, missing springs,damaged adjuster.
Fernando - August 5, 2017
Tool Type
Nailer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Socket set, Wrench Set
Replaced damaged parts,use new -o- rings lube and adjusted. Tested .
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Air leakage from upper cylinder
Richard - April 29, 2017
Tool Type
Nailer
Difficulty
Medium
Time
30-60 minutes
Tools Used
Screwdriver, Socket set, Hex key, impact diver
Disassembled unit from cylinder cap to piston bumper. Removed all cracked and damaged seals including cylinder plate. Cleaned all old lube and dried paste-like residue. Used plenty of air tool line for seal replacement. I found it was important to warm up the deals to facilitate installation.
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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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