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Sierra 18-7853-1 Aluminum Fuel/Water Separator Filter Bracket – 1/4" NPT

Original price $56.89 - Original price $56.89
Original price
$56.89
$56.89 - $56.89
Current price $56.89
Item locally warehoused

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Sierra Aluminum Fuel/Water Separator Filter Bracket – 1/4" NPT

Part Number: 18-7853-1 (distributor SKU: 47-78531)
Brand: Sierra International
UPC: 808282236748
Type: Fuel/water separator filter bracket / filter head
Material: Aluminum
Port size: 1/4" NPT

Product Overview

Replacement aluminum filter bracket (filter head) for compatible Sierra spin-on marine fuel/water separator assemblies. This bracket provides the fixed mounting point and fuel-line inlet/outlet connections for the filter. Used in both gasoline engine fuel systems where a spin-on fuel/water separator is installed. Matches multiple OEM cross-references including Mercury/MerCruiser, Yamaha, and other brands.

  • Cast aluminum construction
  • Port size: 1/4" NPT (inlet and outlet)
  • Provides mounting point and fuel-line connections for the filter assembly
  • Weight: 476 g

Compatible Filter Assemblies

  • Sierra 18-79912 — tall-filter fuel/water separator assembly
  • Sierra 18-7983-1 — short-filter fuel/water separator assembly
  • Sierra 18-7982-1 — tall-filter fuel/water separator assembly
  • Sierra 18-7966-1 — high-capacity fuel/water separator assembly

Fitment Note: Confirm the existing filter head uses 1/4" NPT fuel-line ports before ordering. Sierra offers similar brackets in other port sizes — verify both port thread size and spin-on filter family compatibility before purchase.

OEM Cross-Reference

  • Sierra: 18-7853-1 / 47-78531
  • Mercury / MerCruiser: 55481, 89876, 89876A3
  • Yamaha: MAR-FLTHD-AL-12
  • EMP: 35-06050
  • GLM: 25000
  • Mallory: 9-37860
  • UPC: 808282236748

When to Replace

  • Casting is cracked or physically damaged
  • Mounting threads or fuel-line port threads are stripped or corroded
  • Fuel leakage develops at the filter head connections and cannot be resolved with new seals or fittings
  • Upgrading from a non-aluminum or incompatible filter head

Installation Notes

  • Mount the bracket securely in an accessible location for filter service
  • Connect compatible marine fuel lines using fittings suited to 1/4" NPT threads
  • Use an approved fuel-system thread sealant on all NPT fittings
  • Keep open fittings covered until fuel lines are connected to prevent contamination
  • Inspect all connections carefully for fuel leaks before operating the engine

Related Products

Parts Desk Insights

The two critical specifications for 18-7853-1 are aluminum construction and 1/4" NPT ports. The most common ordering issue is customers not confirming port size — Sierra makes similar brackets in different port sizes, and they are not interchangeable. When a customer needs the complete assembly rather than just the bracket, match the bracket to the correct Sierra spin-on filter family (18-7983-1, 18-7982-1, etc.) before selling. For customers who already have an existing bracket and just need replacement filters, point them to the Sierra 18-7862 or the appropriate spin-on filter for their assembly.

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 1-3 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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