{"product_id":"mercury-diurnal-fuel-tank-cap-36-8m0064067","title":"Mercury – Fuel Tank Diurnal Cap with In-Tank Retainer | Fuel System | 36-8M0064067","description":"\u003cp data-start=\"0\" data-end=\"82\"\u003eMercury – Fuel Tank Diurnal Cap with In-Tank Retainer | Fuel System | 36-8M0064067\u003c\/p\u003e\n\u003chr data-start=\"84\" data-end=\"87\"\u003e\n\u003ch3 data-start=\"89\" data-end=\"103\"\u003eOverview\u003c\/h3\u003e\n\u003cp data-start=\"104\" data-end=\"660\"\u003ePortable fuel tanks take a beating—sun, movement, pressure changes—and the cap is often the first thing to quit on you. When it stops sealing right, you get fuel smell, pressure issues, or a tank that bulges in the sun. This Mercury diurnal cap is the correct replacement for the newer 3.2- and 6.6-gallon tanks. It threads on cleanly, vents the way these tanks are meant to, and uses an in-tank retainer so the cap stays put while you’re fueling. If your cap’s been cracked, loose, or just plain annoying, this one brings the tank back to behaving itself.\u003c\/p\u003e\n\u003chr data-start=\"662\" data-end=\"665\"\u003e\n\u003ch3 data-start=\"667\" data-end=\"685\"\u003eKey Features\u003c\/h3\u003e\n\u003cp data-start=\"686\" data-end=\"1106\"\u003e • \u003cstrong data-start=\"689\" data-end=\"708\"\u003eDiurnal Venting\u003c\/strong\u003e – Manages pressure changes from hot days and cool nights.\u003cbr data-start=\"766\" data-end=\"769\"\u003e • \u003cstrong data-start=\"772\" data-end=\"802\"\u003eStainless Chain \u0026amp; Retainer\u003c\/strong\u003e – Keeps the cap attached so it doesn’t end up in the drink.\u003cbr data-start=\"862\" data-end=\"865\"\u003e • \u003cstrong data-start=\"868\" data-end=\"885\"\u003eEPA-Compliant\u003c\/strong\u003e – Meets 2011 pressed-tank requirements for portable systems.\u003cbr data-start=\"946\" data-end=\"949\"\u003e • \u003cstrong data-start=\"952\" data-end=\"976\"\u003eTight, Reliable Seal\u003c\/strong\u003e – Helps cut down fumes and odd tank pressure issues.\u003cbr data-start=\"1029\" data-end=\"1032\"\u003e • \u003cstrong data-start=\"1035\" data-end=\"1046\"\u003eOEM Fit\u003c\/strong\u003e – Made specifically for Mercury and Quicksilver fuel tanks.\u003c\/p\u003e\n\u003chr data-start=\"1108\" data-end=\"1111\"\u003e\n\u003ch3 data-start=\"1113\" data-end=\"1146\"\u003eEngine \u0026amp; Boat Compatibility\u003c\/h3\u003e\n\u003cp data-start=\"1147\" data-end=\"1269\"\u003e • 3.2-gallon tanks: 8M0054600, 8M0047598\u003cbr data-start=\"1188\" data-end=\"1191\"\u003e • 6.6-gallon tank: 8M0045691\u003cbr data-start=\"1220\" data-end=\"1223\"\u003e • Mercury \/ Quicksilver portable fuel tanks\u003c\/p\u003e\n\u003chr data-start=\"1271\" data-end=\"1274\"\u003e\n\u003ch3 data-start=\"1276\" data-end=\"1314\"\u003ePerformance \u0026amp; Practical Benefits\u003c\/h3\u003e\n\u003cp data-start=\"1315\" data-end=\"1667\"\u003eA proper cap makes the tank behave the way it should. No swelling in the heat, no collapsing at dusk, and no raw fuel smell when you open a storage locker. The venting is tuned for marine use, so the tank breathes just enough without dumping fumes. And the retainer is a simple perk—keeps the cap from rolling around the deck or disappearing overboard.\u003c\/p\u003e\n\u003chr data-start=\"1669\" data-end=\"1672\"\u003e\n\u003ch3 data-start=\"1674\" data-end=\"1691\"\u003eWhy Buy OEM\u003c\/h3\u003e\n\u003cp data-start=\"1692\" data-end=\"1995\"\u003eOEM caps match the threads and sealing surface exactly. They vent correctly and keep pressure where the tank expects it to be. Aftermarket caps often look the part but don’t regulate pressure right, which can lead to hard starts or starving the engine. With an OEM cap, the tank works the way it should.\u003c\/p\u003e\n\u003chr data-start=\"1997\" data-end=\"2000\"\u003e\n\u003ch3 data-start=\"2002\" data-end=\"2011\"\u003eFAQ\u003c\/h3\u003e\n\u003cp data-start=\"2012\" data-end=\"2168\"\u003e\u003cstrong data-start=\"2012\" data-end=\"2061\"\u003eQ1: How do I know my old cap needs replacing?\u003c\/strong\u003e\u003cbr data-start=\"2061\" data-end=\"2064\"\u003e\u003cstrong data-start=\"2064\" data-end=\"2070\"\u003eA:\u003c\/strong\u003e Fuel smell, loose or cracked plastic, or a tank that swells or sucks in with temperature changes.\u003c\/p\u003e\n\u003cp data-start=\"2170\" data-end=\"2274\"\u003e\u003cstrong data-start=\"2170\" data-end=\"2208\"\u003eQ2: Do I need tools to install it?\u003c\/strong\u003e\u003cbr data-start=\"2208\" data-end=\"2211\"\u003e\u003cstrong data-start=\"2211\" data-end=\"2217\"\u003eA:\u003c\/strong\u003e No—just twist off the old one and thread the new cap on.\u003c\/p\u003e\n\u003cp data-start=\"2276\" data-end=\"2417\"\u003e\u003cstrong data-start=\"2276\" data-end=\"2323\"\u003eQ3: What does the diurnal vent actually do?\u003c\/strong\u003e\u003cbr data-start=\"2323\" data-end=\"2326\"\u003e\u003cstrong data-start=\"2326\" data-end=\"2332\"\u003eA:\u003c\/strong\u003e It lets the tank breathe slowly as temperatures change so pressure stays controlled.\u003c\/p\u003e\n\u003cp data-start=\"2419\" data-end=\"2529\"\u003e\u003cstrong data-start=\"2419\" data-end=\"2470\"\u003eQ4: Will this help with tank over-pressurizing?\u003c\/strong\u003e\u003cbr data-start=\"2470\" data-end=\"2473\"\u003e\u003cstrong data-start=\"2473\" data-end=\"2479\"\u003eA:\u003c\/strong\u003e Yes—a proper diurnal cap keeps pressure in check.\u003c\/p\u003e\n\u003cp data-start=\"2531\" data-end=\"2678\"\u003e\u003cstrong data-start=\"2531\" data-end=\"2576\"\u003eQ5: Is the stainless chain really useful?\u003c\/strong\u003e\u003cbr data-start=\"2576\" data-end=\"2579\"\u003e\u003cstrong data-start=\"2579\" data-end=\"2585\"\u003eA:\u003c\/strong\u003e Definitely—keeps the cap with the tank while fueling and saves you from losing it overboard.\u003c\/p\u003e","brand":"Mercury","offers":[{"title":"Default Title","offer_id":46940407234851,"sku":"36-8M0064067","price":33.34,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0783\/7410\/9475\/files\/8m0064067_main.jpg?v=1760631329","url":"https:\/\/partsvu.com\/en-ca\/products\/mercury-diurnal-fuel-tank-cap-36-8m0064067","provider":"PartsVu","version":"1.0","type":"link"}