My Account
Shopping Cart

Sierra 18-1277 Head Gasket Set for MerCruiser 4-Cylinder 3.7L 470

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

18-1277
09/12/2036 5:43 AM
Sale Price

$117.58

In Stock (10+)

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

Authorize Seller Badge
No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-1277 Head Gasket Set is a comprehensive engine sealing kit engineered for the MerCruiser 4-cylinder 3.7L 470 sterndrive engine. This all-in-one kit includes every critical gasket and seal needed for a complete valve grind or top-end engine rebuild, eliminating the need to source individual components separately.

Kit Contents:

  • Head Gasket (Sierra 18-3878) — Replaces OEM part numbers 27-92166, 27-13709, and 27-13709T
  • Intake Manifold Gasket (Sierra 18-0158) — Replaces OEM 27-70905
  • Quadrajet Carburetor Mounting Gasket (Sierra 18-2848)
  • Valve Cover Gasket — Replaces OEM 27-73666
  • Exhaust Manifold Mounting Gasket — Replaces OEM 27-68715
  • Valve Stem Seals — Replaces OEM 26-75413

Sierra International is a trusted manufacturer of marine engine components, producing parts built to meet or exceed original equipment specifications. The 18-1277 gasket set provides a reliable, cost-effective solution for restoring proper compression and preventing oil, coolant, and combustion gas leaks on the MerCruiser 470 platform. Verify your engine's OEM part numbers against those listed above before ordering to ensure correct fitment.

Need more details about products

shipping is a bit high

Like the free delivery and prices

easy

Will keep in consideration for next purchase.

Competitive pricing. Easy to use website. Very fast shipping. Will be shopping here again in the future!

Great products offered at an amazing price! Quick response times and shipping. Will do business with Autoplicity again!

Fast checkout

This is my first time (but definitely not my last) to use Autoplicity. After doing several searches for the Air Lift helper springs Autoplicity beat everyone by at least 20 dollars. Another nice shock was they have very reasonable shipping rates.

nice offering of piston ring compressors!

It was easy and the price is good, but this is just the order. If I get the product in the same manor, that will be great. Thanks, Mike

Fast and easy

Absolute lowest price on the web. Correspondance was great letting me know every step of the purchase and shipping process right up to a tracking number.<br>Ordered Tue. got tracking number Friday ... great job great savings.<br><br>I highly recommend doing business with this fine company!!

Great prices & fast shipping.

Easy to find parts on web site, great prices, great customer service!

Best price I can find on my item and fast shipping. Thinking about becoming a member to order all my parts for my racing team.

Share icon
Return Policy
Returns are easy at Boatplicity

Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy