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Transfer Port Cover Gasket – Fits Mercury 80-85 HP Outboards (Replaces 27-62107)

Regular price $6.50
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You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This aftermarket Transfer Port Cover Gasket is a direct-fit replacement for Mercury Merc 800 & 850 model 4-cylinder outboards from 1970–1975, with 80-85 HP ratings.

It serves as a direct interchange for Mercury part number 27-62107, Sierra 18-0906, and Quicksilver 27-62107.

  • Installs as a direct replacement for the original part.
  • Designed for use on Mercury transfer port cover assemblies.
  • Includes one gasket.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number Notes
Mercury 27-62107 Related Part: 508788
Quicksilver 27-62107 OEM Manufacturer
Sierra 18-0906 Aftermarket Replacement

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This gasket is designed for specific 4-cylinder Mercury outboards. Please verify your model and serial number range below.

Brand Model Rated HP Years OEM Part No. Notes
Mercury 800 (4 CYL.), 80 (4 CYL.) 80 1970–1975 27-62107 Serial numbers 2559001-3493912
Mercury 850 (4 CYL.) 85 1970–1975 27-62107 Serial numbers 3493913-4366801
Mercury 850 (4 CYL.) 85 1970–1975 27-62107 Serial numbers 7010108-7071372
Mercury 850 (4 CYL.) 85 1970–1975 27-62107 Serial numbers 8005440-8043774
Mercury 850 (4 CYL.) 85 1970–1975 27-62107 Serial numbers 9011604-9110013

Technical Specs

Product Type
Transfer Port Cover Gasket
Installation
Direct replacement
Dimensions
43.0 cm x 16.5 cm x 0.3 cm
OEM Reference
Mercury 27-62107
Manufacturer
Quicksilver (OEM) / Sierra (Aftermarket)
Application Note
Used on Mercury transfer port cover assemblies

What’s in the Box

  • 1 x Transfer Port Cover Gasket (27-62107)

Installation Notes

  1. Ensure the engine is off and the battery is disconnected.
  2. Remove the transfer port cover and the old gasket.
  3. Thoroughly clean and dry the mating surfaces on both the engine block and the cover. Remove all old gasket material and residue.
  4. Carefully place the new gasket in position, ensuring it aligns with all bolt holes.
  5. Reinstall the transfer port cover and tighten the bolts in a crisscross pattern to the manufacturer-specified torque.
  6. Reconnect the battery, start the engine, and inspect carefully for any fuel or exhaust leaks around the cover.

Troubleshooting & FAQ

How do I verify this gasket fits my exact Mercury outboard?

Check the Engine & Model Compatibility table. Your engine model, year, and serial number must fall within the specified ranges. Comparing your old gasket to the product images is also a reliable way to confirm fitment.

What are common signs of a failing transfer port cover gasket?

Symptoms include a visible fuel/oil leak around the transfer port cover, poor engine idling, loss of power, or difficulty starting. A visual inspection may reveal a cracked or deteriorated gasket seal.

Is any sealant or adhesive required during installation?

Generally, this type of gasket is installed dry on clean, smooth mating surfaces. However, always consult your engine's specific service manual for the manufacturer's recommendation, as some applications may call for a light application of a non-hardening sealant.

What is the difference between this part and the original OEM gasket?

While the original Mercury part (27-62107) is no longer available from most sources, this aftermarket replacement is manufactured to meet or exceed original specifications for material and fit. It provides a reliable seal at a better value.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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