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Thermostat Cover Gasket 27-8503181

Satisfaction rating 5 out of 5 (18 Ratings)
$3.95
You save $0.85. (18%) $4.8
ONLY 3 REMAINING
Ships Immediately
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Product Description

Mercury factory part. Search for more factory parts & parts diagrams.

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18 Product Reviews

Mercury Optimax 225 Hp

Repair Difficulty
Medium
Repair Time
30 to 60 mins
by

Problem fixed: Cleaning thermostats

Removed thermostat covers Cleaned old gasket material off both surfaces Cleaned and tested thermostats Replaced covers with new gaskets This was done without removing or backing off the fuel rails.

by

225 mariner

Très bonne expérience
by

Mercury optimax 225hp

It was a good run I received the parts that I ordered in a timely manner Will check store as my go to if and when I need parts again. THANKS
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My go to store for mercury parts
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Great place to buy from
by

Repair Difficulty
Easy
Repair Time
Less than 30 mins
Great
by

225 optimax

Repair Difficulty
Medium
Repair Time
1 to 2 hours
Great, got all parts ordered in a timely manner.
by

Problem fixed: Coolant flow issues

Replaced thermostats and temp sensors.

by

Greate services.
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They went out of their way to make sure I got my parts when they said I would.
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Crowley provides a great service for do it yourself boat owners. You provide a single source for many parts that I would have to special order from a local marina. And best of all they get delivered to my doorstep.
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merc optimax 225

Repair Difficulty
Easy
Repair Time
1 to 2 hours
purchased parts, all were correct. received in acceptable time frame. no problems.
by

Problem fixed: engine overheat

replace thermostat gaskets and poppet valev gaskets. replace flush port check valve

2005 Mercury optimax 225

Repair Difficulty
Professional
Repair Time
1 to 2 hours
Awesome. I'm a full time charter captain and Crowley has the best parts diagrams and part price/availability. Makes it easy to do my own mechanic work and maintenance.
by

Problem fixed: Stalling at idle, oil leak, saltwater leak at compressor

Replaced parts according to your diagrams

Product Fitment Grid

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Customers Also purchased

Supersession Chain

Name SKU Superceding SKU
Thermostat Cover Gasket VIEWING THIS PRODUCT 8503181 CURRENT
Thermostat Cover Gasket 850318 8503181

Aftermarket Product Interchange

Name SKU Price Brand
Thermostat Cover Gasket 18-3675 - Sierra Marine
Due to manufacturer policy OEM Mercury products can only be shipped to addresses within the United States.