Aftermarket GRACO® 4426-G Gun Repair Kit - includes: "G" thread diffuser (7/8") & ball holder (Non-OEM)
Aftermarket GRACO® 4426-G Gun Repair Kit - includes: "G" thread diffuser (7/8") & ball holder (Non-OEM)
Manufacturer: Total Finishing Supplies
Part Number: 13278
Comparable OEM Part Number: 4426-G
Description: Total Finishing's part # 20-2392 is a direct-fit replacement for the 300/400 Gun "G" Diffuser & Ball Mount assembly, a wear-prone component in Graco's 300 and 400 series spray guns. This kit supplies the diffuser and ball mount elements that control fluid atomization and spray pattern consistency during high-volume coating work.
Professional painting contractors and airless spray equipment specialists rely on this assembly to maintain uniform spray characteristics across exterior and industrial finish applications. When the diffuser or ball mount degrades, spray pattern quality deteriorates and material waste increases—making timely replacement essential for job site efficiency.
Common reasons for replacement:
Diffuser erosion or scoring from prolonged fluid contact, causing uneven or fan-shaped spray patterns
Ball mount wear or sticking that restricts fluid flow adjustment or creates dead spots in coverage
Corrosion or material buildup on diffuser surfaces, reducing atomization efficiency
Improper spray pattern or pulsing during application, indicating internal component degradation
Manufactured to OEM-equivalent dimensions for proper fit and performance. Compatible Graco equipment models are listed in the Compatible Equipment section below, where available.
Comparable to GRACO® 4426-G
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