Power Head Base Gasket for Mercury & Mariner Outboards

Premium-quality aftermarket power head base gasket for selected Mercury and Mariner 30 HP, 40 HP, 50 HP, 55 HP and 60 HP 2-stroke outboard engines.

Suitable for selected 2-cylinder and 3-cylinder models from 1991 onwards.

Designed to seal between the powerhead and exhaust / driveshaft housing and manufactured to OEM specifications for accurate fitment and reliable sealing.

Fits Mercury & Mariner Outboards

30 HP

2 Stroke
2 Cylinder & 3 Cylinder
Selected 1991 & Up models

40 HP

2 Stroke
2 Cylinder & 3 Cylinder
Selected 1991 & Up models

50 HP

2 Stroke
3 Cylinder
Selected 1991 & Up models

55 HP

2 Stroke
3 Cylinder
Selected 1991 & Up models

60 HP

2 Stroke
3 Cylinder
Selected 1991 & Up models

Replaces Mercury / Mariner Part Numbers

27-8M0000822
8M0000822
27-812865
812865
27-822420
822420
27-828553
828553

OEM part numbers are used for reference only.

Product Features

Power head base gasket
For selected Mercury & Mariner outboards
30 HP, 40 HP, 50 HP, 55 HP & 60 HP
2-stroke applications
Selected 2 & 3-cylinder engines
Selected 1991 & Up applications
Premium-quality aftermarket replacement
Marine-grade construction
Manufactured to OEM specifications
Designed for accurate fitment and reliable sealing
New replacement part

Important – Power Head Base Gasket

This is the power head base gasket, used between the powerhead and lower engine / driveshaft housing assembly.

It is not a cylinder head gasket.

Please check your original part number and engine details before ordering.

Important – Please Check Compatibility

Please do not order by horsepower or appearance alone.

Mercury and Mariner produced numerous 2-stroke configurations, and the same horsepower can use different gaskets depending on model, cylinder configuration and serial number.

Before purchasing, please check:

Engine horsepower
2 or 3-cylinder configuration
Engine model
Engine serial number
Existing gasket
Original Mercury / Mariner part number

If the gasket looks the same as yours, this does not always mean it is the correct one for your outboard.

If you are unsure, please send us your engine serial number before purchasing and our technical team will be happy to check compatibility.

Why Buy From SSI Marine?

Premium aftermarket & OEM-spec marine parts
Workshop-tested products
More than 10 years supplying outboard parts
UK stock
Same working day dispatch before 1 PM Monday–Friday
Royal Mail Tracked 24
Technical support from experienced outboard specialists
Collection available from Leigh, Greater Manchester

Mercury Mariner Outboard 30 HP 40 HP 50 HP 55 HP 60 HP 2 Stroke Power Head Base Gasket 8M0000822