{"product_id":"engine-block-heater-for-jeep-wrangler-1987-2006-4-0l-4-2l","title":"Engine Block Heater for Jeep Wrangler (1987-2006) 4.0L 4.2L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eCold-Start Freeze Plug Engine Block Heater for 1987-2006 Jeep Wrangler (YJ \/ TJ)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The \u003cstrong\u003eZerostart 3100072\u003c\/strong\u003e Engine Block Heater directly warms internal engine coolant on the 1987-2006 Wrangler to eliminate severe cold-start wear and provide immediate cabin heat in freezing ambient conditions.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Jeep Wrangler Cold Weather Weakness\u003c\/h3\u003e\n\u003cp\u003eThe heavy cast-iron construction of the \u003cstrong\u003eAMC 242\u003c\/strong\u003e (4.0L) and \u003cstrong\u003eAMC 258\u003c\/strong\u003e (4.2L) inline-six engines acts as a massive thermal sink in sub-freezing weather. Frigid temperatures drastically thicken motor oil, delaying hydrodynamic oil pressure to critical flat-tappet camshaft lobes, lifters, and rod bearings during initial cranking. This severe friction accelerates internal bore wear, strains the starter motor and battery, and results in extended cold-idle fuel wash down the cylinder walls.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis 600-watt, 120-volt direct immersion heating element installs directly into the engine water jacket via a 2-inch freeze core hole. By transferring heat straight into the engine coolant through thermal convection, it maintains elevated block temperatures overnight. The unit features heavy-duty brass element construction for galvanic corrosion resistance and a positive O-ring seal to prevent coolant seepage under thermal expansion cycles. Pre-heating the iron block preserves oil viscosity, ensures immediate cold-weather ignition, and drastically mitigates bearing starvation on sub-zero starts.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\n  \u003ctable width=\"100%\" style=\"border-collapse: collapse; border: 1px solid #e0e0e0; font-size: 14px; min-width: 300px;\"\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eFitment\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e1987-2006 Jeep Wrangler\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eEngine \/ Chassis\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eAMC 242 (4.0L) \u0026amp; AMC 258 (4.2L) \/ YJ \u0026amp; TJ\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eStock Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e112-190 hp \/ 210-235 lb-ft\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eReplaces OEM Part #\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eZerostart 3100072 (Replaces Mopar 82201506)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1987-1990 Jeep Wrangler YJ (4.2L AMC 258 Inline-6)\u003c\/li\u003e\n  \u003cli\u003e1991-1995 Jeep Wrangler YJ (4.0L AMC 242 Inline-6)\u003c\/li\u003e\n  \u003cli\u003e1997-2006 Jeep Wrangler TJ (4.0L AMC 242 Inline-6)\u003c\/li\u003e\n  \u003cli\u003e2004-2006 Jeep Wrangler Unlimited LJ (4.0L AMC 242 Inline-6)\u003c\/li\u003e\n  \u003cli\u003eNote: Fits 2-inch freeze plug ports only; does not fit 2.4L, 2.5L, or modern V6\/V8 conversions.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the YJ and TJ Wrangler?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 1987-2006 Jeep Wrangler equipped with the AMC 242 4.0L or AMC 258 4.2L inline-six engine.\u003c\/p\u003e\n\n\u003ch4\u003eWhich block location is used for installation?\u003c\/h4\u003e\n\u003cp\u003eThis unit installs directly in place of a factory 2-inch freeze (core) plug on the engine block after draining the cooling system.\u003c\/p\u003e\n\n\u003ch3\u003eThe Jeep Trail Durability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to handle extreme winter conditions, this immersion heater maintains cast-iron block readiness so your Wrangler cranks reliably without mechanical wear on frozen backcountry trails.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":67539486834936,"sku":"DS-E9QABEQE7","price":64.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/engine-block-heater-for-jeep-wrangler-1987-2006-4-0l-4-2l-1.jpg?v=1790650237","url":"https:\/\/performancechiptuning.com\/products\/engine-block-heater-for-jeep-wrangler-1987-2006-4-0l-4-2l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}