• 144791 Mercury MerCruiser Diaphragm | Genuine Quicksilver OEM Part
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144791 Mercury MerCruiser Diaphragm | Genuine Quicksilver OEM Part

144791 Mercury MerCruiser Diaphragm | Genuine Quicksilver OEM Part

$36.20 AUD
$36.20 AUD
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🔧 Product Description

Genuine Quicksilver Poppet Valve Diaphragm - Part Number: 14479 1

A genuine Quicksilver diaphragm used in Mercury V6 cooling system poppet / pressure relief valve assemblies. This diaphragm is used on selected Mercury 2.5L EFI, DFI, Pro XS, XS, Jet and V6 outboards where the cooling-system pressure relief valve diagram specifies 14479 1.

⚙️ Key Features

  • Genuine Quicksilver OEM diaphragm
  • Correct Mercury part number 14479 1
  • Also commonly written as 144791
  • Supersedes earlier 14479 reference
  • Used in Mercury V6 poppet / cooling system pressure relief assemblies

🚤 Compatibility

Commonly used on

  • Mercury 2.5L V6 cooling system pressure relief / poppet valve assemblies
  • Mercury EFI / DFI / Optimax / XS / Pro XS poppet valve diaphragm service
  • Mercury Jet and performance V6 outboard cooling systems where 144791 is specified

Typically suits

  • Engine models:
  • Mercury 110 Jet 2.5L - serial 1B690542 to 1B974227
  • Mercury 135HP V6 2.5L - serial 0T178500 to 0T800999
  • Mercury 135HP V6 2.5L - serial 0T801000 to 1B226999
  • Mercury 135HP V6 2.5L - serial 1B227000 to 1B417701
  • Mercury 135HP V6 2.5L - serial 1B417702 to 1B737495
  • Mercury 140 Jet - serial 0G960500 to 0T178499
  • Mercury 150 Pro XS 2.5L - serial 1B690542 to 2B535572
  • Mercury 150HP V6 2.5L - serial 0T178500 to 0T800999
  • Mercury 150HP V6 2.5L - serial 0T801000 to 1B226999
  • Mercury 150HP V6 2.5L - serial 1B227000 to 1B417701
  • Mercury 150HP V6 2.5L - serial 1B417702 to 1B580029
  • Mercury 175 Pro XS 2.5L - serial 1B516339 to 2B535624
  • Mercury 175HP V6 2.5L - serial 0T178500 to 0T800999
  • Mercury 175HP V6 2.5L - serial 0T801000 to 1B226999
  • Mercury 175HP V6 2.5L - serial 1B227000 to 1B417701
  • Mercury 175HP V6 2.5L - serial 1B417702 to 1B508457
  • Mercury 200 XS 2.5L - serial 0T235000 to 0T818180
  • Mercury 200 XS 2.5L - serial 0T818181 to 1E000796
  • Mercury 200 XS 2.5L - serial 1E000797 to 1E002110
  • Mercury 200 XS 2.5L ROS - serial 1E050852 to 1E053876
  • Mercury 200 XS SST 2.5L - serial 1E050629 to 1E053875
  • Mercury 225X EFI Pro Max - serial 0T430254 to 0T819605
  • Mercury V-135 - serial 0G960500 to 0T178499
  • Mercury V-140 International - serial 0T178500 to 1B226999
  • Mercury V-150 - serial 0G960500 to 1B226999
  • Mercury V-150 EFI 2.5L - serial 0T409000 to 0T800999
  • Mercury V-150 EFI 2.5L - serial 0T801000 to 1B226999
  • Mercury V-150 EFI 2.5L - serial 1B227000 and up
  • Mercury V-175 EFI 2.5L - serial 0T409000 to 0T800999
  • Mercury V-200 - serial 0G960500 to 1B226999
  • Mercury V-200 EFI 2.5L - serial 0T409000 to 0T800999
  • Mercury V-200 EFI 2.5L - serial 0T801000 to 1B226999
  • Mercury V-200 EFI 2.5L - serial 1B227000 and up
  • Mercury XR-6 / Magnum III - serial 0G960500 to 1B226999
  • HP Range: commonly 110 Jet - 225HP where specified
  • Engine Type: Mercury 2.5L V6 EFI / DFI / Optimax / performance outboard
  • System Type: Cooling system poppet / pressure relief valve diaphragm

🔌 Function

The diaphragm forms part of the poppet / pressure relief valve assembly. It responds to cooling-system pressure and helps regulate water flow through the engine at different RPM and load conditions.

⚠️ Common Signs of Failure

  • Overheating at idle or high RPM
  • Weak or inconsistent cooling water pressure
  • Diaphragm torn, stiff or distorted
  • Water leakage around poppet valve cover
  • Engine temperature fluctuating under load
  • Cooling-system service required after salt or debris build-up

🔄 Supersession & Cross Reference

OEM Supersession Chain

  • 14479 1 → Supersedes 14479
  • 14479 earlier diaphragm reference

OEM / Related Numbers

  • 14479 1
  • 144791
  • 14479
  • 27-8M0046715 related gasket set reference in some 2.5L powerhead assemblies
  • 828343A05 related exhaust divider plate kit reference
  • 814754 related seal reference
  • 19050 6 related gasket reference
  • Poppet valve diaphragm reference for 2.5L Mercury V6 cooling-system assemblies

Aftermarket / Verified Equivalents

  • No aftermarket equivalent

📦 Condition

  • Genuine Quicksilver part
  • Brand new
  • Supplied in original or equivalent packaging

Shipping & Delivery

Flat-rate shipping Australia-wide — $14.99 per order, no matter how many parts you add. Orders dispatch from our Kadina, South Australia store. Need it urgently or want to collect in person? Call us on 0412 532 984 before ordering.

Returns & Warranty

14-day change-of-mind returns — if it's not right or you ordered the wrong part, send it back within 14 days in new, unused condition for a refund or exchange. Manufacturer warranties apply to new parts. Full details in our Refunds & Returns policy.

Not sure this fits?

Ask us before you buy — we check part numbers and fitment every day. Call 0412 532 984 (Mon–Fri 8.30am–4.30pm) or message us through the contact page with your engine or vehicle details.

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