{"product_id":"koyorad-radiator-cap-sk-c13-16-lb-pressure-oe-grade-universal-fit-corrosion-resistant","title":"Koyorad Radiator Cap SK-C13 16 lb Pressure — OE-Grade Universal Fit, Corrosion-Resistant","description":"\u003cp\u003e\u003cstrong\u003eThe Koyorad Koyo SK-C13 Radiator Cap is a 16 lb, OE-grade replacement cap engineered to maintain proper cooling-system pressure and reliable seals for Koyorad radiators and universal applications.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eBuilt from durable materials selected to match original-equipment standards, the SK-C13 cap is designed for long-term exposure to engine bay heat and road conditions. Koyorad uses aluminum, brass, copper and heat-resistant plastics in its components so the cap resists corrosion, spring fatigue and seal hardening that can lead to coolant loss or pressure failure. This is a simple, direct part intended to restore correct pressure control in compatible radiators.\u003c\/p\u003e\n\n\u003ch3\u003eHow does the SK-C13 maintain the correct cooling-system pressure?\u003c\/h3\u003e\n\u003cp\u003eThe SK-C13 holds a 16-pound (psi) pressure rating to keep coolant in the radiator until the system reaches the intended boiling point. A calibrated spring-loaded valve opens at the set pressure to let excess coolant flow to the overflow reservoir, then closes to reseal the system as it cools. The reliable spring and valve tolerances help reduce premature venting and coolant evaporation.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e16 lb pressure rating suitable for higher-boiling coolant performance\u003c\/li\u003e\n  \u003cli\u003eSpring-loaded relief valve calibrated for repeatable opening\/closing\u003c\/li\u003e\n  \u003cli\u003eDurable elastomer seal to prevent slow leaks and vapor loss\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat materials and construction features extend the cap’s lifespan?\u003c\/h3\u003e\n\u003cp\u003eKoyorad selects OE-grade metals and plastics that withstand heat cycling and corrosive coolant environments. Key components — such as the valve, spring and sealing surfaces — are crafted from corrosion-resistant metal and high-temperature elastomers, minimizing wear and seal degradation over time. This construction reduces the need for frequent replacements in most driving conditions.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCorrosion-resistant metal components (aluminum, brass, copper)\u003c\/li\u003e\n  \u003cli\u003eHeat-stable plastic and elastomer seals resistant to hardening\u003c\/li\u003e\n  \u003cli\u003ePrecision assembly that maintains valve tolerances across cycles\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eIs the SK-C13 compatible with my radiator or vehicle?\u003c\/h3\u003e\n\u003cp\u003eThe SK-C13 is specified as a universal-type 16 lb radiator cap intended for use with Koyorad radiators and many aftermarket or OE systems that accept this size and pressure rating. Confirm fitment by comparing cap diameter, seat style and pressure rating to your original part. When in doubt, check Koyorad compatibility charts or consult a service manual for seat dimensions and required pressure.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eUniversal 16 lb cap fits many radiators using the same seat style\u003c\/li\u003e\n  \u003cli\u003eRecommended for direct replacement on compatible Koyorad radiators\u003c\/li\u003e\n  \u003cli\u003eMeasure cap seat and verify 16 psi requirement before installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow should I install and maintain the SK-C13 for best results?\u003c\/h3\u003e\n\u003cp\u003eInstallation is straightforward: ensure the radiator neck and mating surfaces are clean, press the cap on and twist until it locks into place. Inspect the seal periodically for cracks or hardening and replace the cap if the spring feels loose or if coolant leaks occur. Proper coolant level and overflow tank condition also help the cap function correctly.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eClean filler neck before mounting to ensure a tight seal\u003c\/li\u003e\n  \u003cli\u003eTurn to lock; listen and feel for secure engagement\u003c\/li\u003e\n  \u003cli\u003eInspect seals and spring annually or during coolant service\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho this product is for: The Koyorad Koyo SK-C13 Radiator Cap is aimed at DIY mechanics, professional technicians and vehicle owners who need a durable, OE-grade 16 lb replacement for Koyorad or similarly configured radiators. It's a practical choice when restoring proper pressure control after maintenance, replacing a worn or leaking cap, or upgrading to a reliable, long-lasting component for everyday driving and performance applications.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: What pressure rating does the Koyo SK-C13 have?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: The SK-C13 is rated at 16 psi, designed to maintain proper system pressure until the relief valve opens.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can I use this cap on non-Koyorad radiators?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes, if the filler neck seat style and 16 psi requirement match your radiator; verify dimensions before installing.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Koyorad","offers":[{"title":"Default Title","offer_id":48086764978334,"sku":"B007TNIOCC","price":53.15,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/koyorad-koyo-sk-c13-front-view.jpg?v=1785904137","url":"https:\/\/northtrailauto.ca\/products\/koyorad-radiator-cap-sk-c13-16-lb-pressure-oe-grade-universal-fit-corrosion-resistant","provider":"North Trail Auto","version":"1.0","type":"link"}