Mercury Quicksilver NEW OEM Piston Ring Set 39-88392A12 .030 OS 35-115HP 0810

Mercury / Quicksilver OEM Piston Ring Set — Part Number 39-88392A12
Brand: Mercury / Quicksilver | Condition: New Old Stock (NOS)

You are purchasing a genuine Mercury / Quicksilver OEM Piston Ring Set, part number 39-88392A12. This .030" oversize ring set contains 12 piston rings for use during engine rebuilds on Mercury and Mariner 35HP–115HP 3-cylinder and 4-cylinder 2-stroke outboard motors. Oversize rings are required when the cylinder bores have been re-bored .030" over standard diameter during engine reconditioning. This is an authentic factory original part — never installed, never used.

Condition Details: This is a New Old Stock (NOS) part. The ring set itself is in new, uninstalled condition. As is common with NOS inventory, the original packaging may show signs of age, including shelf wear, dust, or minor cosmetic blemishes on the bag or box. The parts are new and fully functional.

Specifications:

• Type: Piston Ring Set
• Oversize: .030" (0.76mm) over standard bore
• Quantity: 12 rings per set
• Application: 3-cylinder and 4-cylinder 2-stroke engines

Part Number / Supersede Information:

• Primary OEM Part Number: 39-88392A12 / 88392A12
• This part number may have been superseded by an updated Mercury/Quicksilver part number. We recommend verifying any current supersede numbers through your local Mercury Marine dealer or the official Mercury parts catalog prior to ordering.

Compatible Equipment (partial list — Mercury/Mariner 2-stroke outboards):

• Mercury/Mariner 35HP–115HP — 3-cylinder and 4-cylinder 2-stroke outboard engines (select models requiring .030" OS pistons)
• Confirmed use in 4-cylinder crankshaft/piston assembly (ref. #90-13289) and 70HP 3-cylinder assembly (ref. #90-90647)
• ⚠ Oversize rings — for use only when cylinder bores have been re-bored .030" over standard diameter. Verify bore size and engine specifications before ordering.

Why Choose OEM Parts? OEM parts are engineered and manufactured to exact factory tolerances, ensuring a precise fit, reliable performance, and long service life. Unlike aftermarket alternatives, OEM parts are designed specifically for your equipment — no modifications, no guesswork.

Returns: We proudly offer hassle-free returns. If you are not completely satisfied with your purchase for any reason, simply open a return request through eBay within 30 days of purchase and we will take care of you promptly.

Thank you for choosing QBS Parts Inc! We truly appreciate your business. If you have any issues whatsoever with your order, please give us the opportunity to resolve it before leaving feedback — we are committed to making every transaction a great experience.

Please verify fitment and bore size using your engine's model and serial number before purchasing. Feel free to message us with any questions — we're here to help!

QBS Parts, Inc. — Gardena, CA