{"product_id":"cummins-leak-free-rear-welsh-plug","title":"Leak-Free Rear Welsh Plug for 4BT and 6BT Cummins","description":"\u003ch1\u003eLeak-Free Rear Welsh (Freeze) Plug for 4BT \u0026amp; 6BT Cummins\u003c\/h1\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eThe factory rear welsh plug is a common failure point on Cummins engines, especially in high-performance, towing, and heavy-duty applications. Increased boost and cylinder pressures can cause factory plugs to leak or blow out, leading to coolant loss, downtime, and expensive repairs.\u003c\/p\u003e\n\u003cp\u003eThe \u003cstrong\u003eEPC Leak-Free Rear Welsh (Freeze) Plug\u003c\/strong\u003e is engineered to provide a permanent solution. Precision-machined from billet material and supplied with premium sealing components, it delivers superior strength, reliability, and serviceability compared to the factory design.\u003c\/p\u003e\n\u003ch2\u003eVehicle Compatibility\u003c\/h2\u003e\n\u003cp\u003e✔ 4BT Cummins\u003cbr\u003e✔ 6BT 12 Valve Cummins\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOnly one rear plug is required per engine.\u003c\/strong\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eWhy Choose the EPC Rear Welsh Plug?\u003c\/h2\u003e\n\u003cp\u003e✅ \u003cstrong\u003eBillet Construction\u003c\/strong\u003e\u003cbr\u003ePrecision-machined for exceptional strength and long-term durability.\u003c\/p\u003e\n\u003cp\u003e✅ \u003cstrong\u003eLeak-Free Sealing System\u003c\/strong\u003e\u003cbr\u003eUtilises a high-temperature Viton O-ring to ensure a reliable seal under extreme conditions.\u003c\/p\u003e\n\u003cp\u003e✅ \u003cstrong\u003eBuilt for High-Boost Applications\u003c\/strong\u003e\u003cbr\u003eDesigned to withstand the cylinder pressures and cooling system demands that commonly cause factory plugs to fail.\u003c\/p\u003e\n\u003cp\u003e✅ \u003cstrong\u003eCorrosion-Resistant Components\u003c\/strong\u003e\u003cbr\u003eSupplied with stainless steel hardware for maximum corrosion resistance and service life.\u003c\/p\u003e\n\u003cp\u003e✅ \u003cstrong\u003eAdded M8 threads for EPC solid heater lines (ETA August 2026)\u003c\/strong\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e✅ Integrated pilot dimple to aid in installing sensors.\u003cbr\u003e\u003c\/strong\u003eWe added a pilot dimple for those wanting to use the rear plug for sensors or a coolant bypass. Simply drill and tap to accomodate any threads you need.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eWhat's Included?\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eBillet Leak-Free Rear Welsh (Freeze) Plug\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHigh-Temperature Viton O-Ring\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eStainless Steel Fastening Hardware\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003cp\u003eWhether you're building a competition truck, tow rig, or reliable street-driven Cummins, the EPC Leak-Free Rear Welsh Plug provides peace of mind where it matters most.\u003c\/p\u003e\n\u003ch3\u003eLeak-Free for Life.\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eRecommended product page callout:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e⚠️ \u003cstrong\u003eThis listing is for the REAR Welsh (Freeze) Plug only. One plug is required per engine.\u003c\/strong\u003e\u003c\/p\u003e\n\u003c!----\u003e","brand":"Engineering Performance Concepts","offers":[{"title":"Blue","offer_id":51787358142785,"sku":"BRWPBU","price":99.99,"currency_code":"AUD","in_stock":true},{"title":"Black","offer_id":51787358175553,"sku":"BRWPBK","price":99.99,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0883\/5022\/8801\/files\/WhatsApp_Image_2026-05-22_at_9.57.34_AM.jpg?v=1779407904","url":"https:\/\/engineeringperformanceconcepts.com\/products\/cummins-leak-free-rear-welsh-plug","provider":"Engineering Performance Concepts ","version":"1.0","type":"link"}