{"product_id":"mercury-water-pump-base-face-plate-gasket-27-39625","title":"Mercury 27-39625 Water Pump Base-to-Face Plate Gasket – Lower","description":"\u003csection class=\"product-description\"\u003e\n\n\u003cp\u003eThe \u003cstrong\u003eMercury 27-39625\u003c\/strong\u003e is a genuine OEM \u003cstrong\u003elower water pump gasket\u003c\/strong\u003e used in selected Mercury and Mariner outboard lower units. It installs between the \u003cstrong\u003ewater pump base and the stainless face plate\u003c\/strong\u003e, sealing that joint so the impeller maintains proper suction and cooling-water flow to the powerhead. One gasket is required per applicable water-pump assembly.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Applications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMercury 20 HP\u003c\/strong\u003e — from approximately serial number 1558310 and up\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMercury 200 \/ 20 HP-series\u003c\/strong\u003e models — confirm by serial number range and water-pump diagram\u003c\/li\u003e\n\u003cli\u003eAny Mercury or Mariner lower unit where the \u003cstrong\u003ewater pump parts diagram calls for 27-39625\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eAlways confirm fitment using the outboard model, horsepower, serial number, and the applicable water-pump parts diagram before ordering. Mercury uses different water-pump gasket shapes across lower-unit families.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch2\u003eWhere It Fits – Assembly Stack\u003c\/h2\u003e\n\u003cp\u003eThis gasket occupies the \u003cstrong\u003elower position\u003c\/strong\u003e in the water pump assembly stack:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWater pump base (bottom)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e27-39625\u003c\/strong\u003e — this gasket (base-to-face plate)\u003c\/li\u003e\n\u003cli\u003eFace plate 39624 (stainless wear plate)\u003c\/li\u003e\n\u003cli\u003e27-396231 \/ 27-39623 — upper face-plate-to-pump-body gasket\u003c\/li\u003e\n\u003cli\u003eWater pump body (top)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eDo not confuse this lower gasket with \u003cstrong\u003e27-396231\u003c\/strong\u003e, which seals the upper side of the face plate to the pump body. They are separate parts and both should be replaced during a full water-pump service.\u003c\/p\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Part Number:\u003c\/strong\u003e 27-39625\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlso Referenced As:\u003c\/strong\u003e 39625\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGTIN:\u003c\/strong\u003e 745061141346\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFactory Description:\u003c\/strong\u003e Gasket, Water Pump Base to Face Plate (Lower)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Paper-composite water pump gasket\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSystem:\u003c\/strong\u003e Outboard raw-water cooling \/ lower-unit water pump\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuantity Required:\u003c\/strong\u003e 1 per water-pump assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen to Replace\u003c\/h2\u003e\n\u003cp\u003eReplace this gasket whenever:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe water pump impeller is being serviced\u003c\/li\u003e\n\u003cli\u003eThe water pump base or face plate is removed for any reason\u003c\/li\u003e\n\u003cli\u003eThe old gasket is torn, compressed, swollen, or brittle\u003c\/li\u003e\n\u003cli\u003eOverheating or weak cooling-water flow is being diagnosed\u003c\/li\u003e\n\u003cli\u003eLeakage is found around the pump base during a lower-unit inspection\u003c\/li\u003e\n\u003cli\u003eThe face plate or water pump base is being replaced\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eA new impeller can still deliver poor cooling performance if this gasket cannot maintain a proper seal at the pump base.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cp\u003eBefore installing the new gasket:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRemove all traces of the old gasket from the pump base and face plate surfaces\u003c\/li\u003e\n\u003cli\u003eClean the mating surfaces carefully — do not gouge aluminum or stainless sealing areas\u003c\/li\u003e\n\u003cli\u003eInspect the \u003cstrong\u003eface plate (39624)\u003c\/strong\u003e for scoring or wear\u003c\/li\u003e\n\u003cli\u003eReplace the upper gasket (\u003cstrong\u003e27-396231\u003c\/strong\u003e) and the base-to-gear-housing gasket (\u003cstrong\u003e27-39626\u003c\/strong\u003e) at the same time when doing a complete service\u003c\/li\u003e\n\u003cli\u003eInspect the impeller, key, pump housing, and O-ring while the assembly is apart\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFollow the applicable Mercury service manual for assembly sequence, impeller-vane orientation, fastener torque, and any required sealing compound. Do not reuse the old gasket or stack gaskets.\u003c\/p\u003e\n\n\u003ch2\u003eAlternate \/ Cross-Reference Part Numbers\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e27-39625 — Mercury OEM\u003c\/li\u003e\n\u003cli\u003e39625 — short-form Mercury reference\u003c\/li\u003e\n\u003cli\u003eSierra 18-2828 — aftermarket cross-reference\u003c\/li\u003e\n\u003cli\u003eGLM 31200 — aftermarket cross-reference\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eCross-reference numbers should be verified against the outboard serial number and water-pump diagram before use as a substitute.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch2\u003eRelated Parts\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/8131442016292\"\u003eMercury MerCruiser Quicksilver Water Pump Repair Kit 8M0135821\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/11167581601828\"\u003eMercury Quicksilver Heavy-Duty Water Pump Kit 8M0137849 – 15 \u0026amp; 20 HP EFI FourStroke\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/8131441983524\"\u003eMercury Outboard Water Pump Impeller 8-Blade – 8M0135803\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/8131399417892\"\u003eMercury Quicksilver Water Pump Base O-Ring 25-26722\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eParts Desk Insights\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eBest Use Case:\u003c\/strong\u003e This is the right part to have on hand any time a customer is servicing the water pump on a Mercury or Mariner 20 HP outboard. At a few dollars, it’s inexpensive insurance during an impeller change — if the pump is already apart, replacing this gasket along with the upper gasket and base O-ring ensures the whole pump assembly seals correctly from the start.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCommon Issues:\u003c\/strong\u003e The most common mistake is ordering only the impeller and skipping the gaskets. Mercury uses two separate gaskets above and below the face plate — 27-39625 below and 27-396231 above — and both should be replaced at the same time. If only one gasket is swapped, a leak at the unsealed joint can reduce cooling efficiency even with a brand-new impeller installed.\u003c\/p\u003e\n\n\u003c\/section\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563856986148,"sku":"39625","price":5.91,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/56b86d8a-a55b-46b3-83e2-e2432305c5eb.png?v=1782769690","url":"https:\/\/marisolmarine.com\/products\/mercury-water-pump-base-face-plate-gasket-27-39625","provider":"Marisol Marine Company","version":"1.0","type":"link"}