{"id":7272,"date":"2026-06-20T09:59:26","date_gmt":"2026-06-20T09:59:26","guid":{"rendered":"http:\/\/australianholden.com\/?p=7272"},"modified":"2026-06-22T10:41:05","modified_gmt":"2026-06-22T10:41:05","slug":"hr-holden-radiator-upgrade-guide","status":"publish","type":"post","link":"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/hr-holden-radiator-upgrade-guide\/","title":{"rendered":"HR Holden Radiator Upgrade Guide"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The HR Holden is widely considered one of Holden&#8217;s finest achievements. Combining attractive styling, improved handling and the durable Red Motor engine family, the HR remains one of Australia&#8217;s most popular classic cars. Whether powered by a 161 or the highly sought-after 186 six-cylinder engine, the HR delivers a driving experience that still appeals to enthusiasts nearly sixty years after its release.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, one area where modern technology can significantly improve the ownership experience is the cooling system. While the factory radiator was perfectly adequate when new, decades of corrosion, sediment build-up and increasing traffic conditions mean many HR Holdens now struggle to maintain ideal operating temperatures.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For owners who regularly drive their cars, tow trailers, travel long distances or have modified engines, a radiator upgrade can dramatically improve reliability and reduce the risk of overheating.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Why Upgrade the HR Holden Radiator?<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Many cooling system problems are blamed on the engine when the radiator is actually the primary culprit.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Common Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Overheating in traffic<\/li>\n\n\n\n<li>Temperature spikes on hot days<\/li>\n\n\n\n<li>Coolant loss<\/li>\n\n\n\n<li>Poor highway cooling<\/li>\n\n\n\n<li>Steam from engine bay<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Causes<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Blocked radiator core<\/li>\n\n\n\n<li>Internal corrosion<\/li>\n\n\n\n<li>Reduced coolant flow<\/li>\n\n\n\n<li>Age-related deterioration<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Even a professionally serviced original radiator may struggle compared to modern cooling technology.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Understanding the Factory Radiator<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The HR Holden originally used a copper-brass radiator design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Advantages<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Durable construction<\/li>\n\n\n\n<li>Easy to repair<\/li>\n\n\n\n<li>Period-correct appearance<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Limitations<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Less efficient than modern alloy radiators<\/li>\n\n\n\n<li>Heavier construction<\/li>\n\n\n\n<li>Smaller cooling capacity<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For original restorations, a rebuilt factory radiator often remains the preferred option.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For regularly driven vehicles, however, upgrades can offer substantial benefits.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Signs Your Radiator Needs Attention<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Before upgrading, it&#8217;s worth identifying common radiator warning signs.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Consistent overheating<\/li>\n\n\n\n<li>Coolant discolouration<\/li>\n\n\n\n<li>Visible corrosion<\/li>\n\n\n\n<li>Coolant leaks<\/li>\n\n\n\n<li>Blocked cooling fins<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Diagnostic Tip<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Use an infrared temperature gun to check temperature variation across the radiator core.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cold sections often indicate blocked tubes.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Direct Replacement Radiator<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Reconditioned Copper-Brass Radiator<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Original appearance<\/li>\n\n\n\n<li>Factory fitment<\/li>\n\n\n\n<li>Maintains authenticity<\/li>\n\n\n\n<li>Easy installation<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Concours restorations<\/li>\n\n\n\n<li>Original vehicles<\/li>\n\n\n\n<li>Collector cars<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A professionally re-cored radiator can often provide decades of reliable service.<\/p>\n\n\n<div id=\"fu_ebay_0\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 0 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_0\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Radiator<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_0 = null;\nvar waitForDepends_fu_ebay_0 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_0);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_0 = jQuery(\"#fu_ebay_0\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Radiator\",\nfu_ebay_query : \"HR Holden Radiator\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 0,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_0.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Best Performance Radiator Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Aluminium Alloy Radiator<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Increased cooling efficiency<\/li>\n\n\n\n<li>Improved heat transfer<\/li>\n\n\n\n<li>Reduced weight<\/li>\n\n\n\n<li>Better performance in hot climates<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Modified engines<\/li>\n\n\n\n<li>Touring vehicles<\/li>\n\n\n\n<li>Summer driving<\/li>\n\n\n\n<li>Daily-driven classics<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Modern aluminium radiators can significantly outperform original copper-brass designs.<\/p>\n\n\n<div id=\"fu_ebay_1\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 1 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_1\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;HR Holden aluminium radiators<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_1 = null;\nvar waitForDepends_fu_ebay_1 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_1);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_1 = jQuery(\"#fu_ebay_1\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"HR Holden aluminium radiators\",\nfu_ebay_query : \"HR Holden aluminium radiators\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 1,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_1.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Single-Core vs Multi-Core Radiators<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">One of the most common upgrade questions involves radiator core design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Single-Core<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Suitable for stock vehicles<\/li>\n\n\n\n<li>Lower cost<\/li>\n\n\n\n<li>Direct replacement<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Triple-Core<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Improved cooling capacity<\/li>\n\n\n\n<li>Better heat dissipation<\/li>\n\n\n\n<li>Ideal for modified engines<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For most HR Holdens fitted with a 186 engine, a quality triple-core radiator offers an excellent balance between originality and performance.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Cooling Fan Upgrade<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Even the best radiator benefits from improved airflow.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Davies Craig Thermatic Electric Fan Kit<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Increased airflow at idle<\/li>\n\n\n\n<li>Reduced engine drag<\/li>\n\n\n\n<li>Better temperature control<\/li>\n\n\n\n<li>Improved traffic performance<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Modified vehicles<\/li>\n\n\n\n<li>Urban driving<\/li>\n\n\n\n<li>Warm climates<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Electric fans solve one of the most common weaknesses of older cooling systems: poor airflow when stationary.<\/p>\n\n\n<div id=\"fu_ebay_2\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 2 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_2\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Davies Craig Thermatic Electric Fan Kit<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_2 = null;\nvar waitForDepends_fu_ebay_2 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_2);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_2 = jQuery(\"#fu_ebay_2\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Davies Craig Thermatic Electric Fan Kit\",\nfu_ebay_query : \"Davies Craig Thermatic Electric Fan Kit\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 2,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_2.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Radiator Hose Upgrades<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Many cooling issues originate from deteriorated hoses rather than the radiator itself.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Coolant leaks<\/li>\n\n\n\n<li>Soft hoses<\/li>\n\n\n\n<li>Swollen sections<\/li>\n\n\n\n<li>Cracking<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Old hoses should always be replaced when upgrading a radiator.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Radiator Hose Kit<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Gates Radiator Hose Kit<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Excellent durability<\/li>\n\n\n\n<li>Reliable sealing<\/li>\n\n\n\n<li>OEM-quality construction<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Cooling system rebuilds<\/li>\n\n\n\n<li>Preventative maintenance<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_3\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 3 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_3\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Gates HR Holden hose kit<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_3 = null;\nvar waitForDepends_fu_ebay_3 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_3);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. 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Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_4 = jQuery(\"#fu_ebay_4\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Tridon\",\nfu_ebay_query : \"Tridon Thermostat HR Holden\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 4,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_4.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Water Pump Upgrades<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Radiators and water pumps work together.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A worn pump can limit coolant circulation regardless of radiator quality.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Overheating<\/li>\n\n\n\n<li>Coolant leaks<\/li>\n\n\n\n<li>Bearing noise<\/li>\n<\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">Best Water Pump Replacement<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Dayco Water Pump<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Improved coolant flow<\/li>\n\n\n\n<li>High-quality bearings<\/li>\n\n\n\n<li>Reliable performance<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Restorations<\/li>\n\n\n\n<li>Touring vehicles<\/li>\n\n\n\n<li>Preventative maintenance<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_5\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 5 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_5\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Water Pump<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_5 = null;\nvar waitForDepends_fu_ebay_5 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_5);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_5 = jQuery(\"#fu_ebay_5\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Water Pump\",\nfu_ebay_query : \"HR Holden water pump\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 5,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_5.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Coolant Selection Matters<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Many cooling problems are caused by incorrect coolant rather than radiator design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Avoid<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Plain water<\/li>\n\n\n\n<li>Cheap universal coolants<\/li>\n\n\n\n<li>Mixing coolant types<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Use<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Quality corrosion-inhibiting coolant<\/li>\n\n\n\n<li>Products designed for classic engines<\/li>\n<\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">Best Coolant for HR Holden<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Penrite Classic Car Coolant<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Corrosion protection<\/li>\n\n\n\n<li>Suitable for older metals<\/li>\n\n\n\n<li>Long service intervals<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Original engines<\/li>\n\n\n\n<li>Restored vehicles<\/li>\n\n\n\n<li>Long-term ownership<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_6\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 6 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_6\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Penrite Classic Car Coolant<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_6 = null;\nvar waitForDepends_fu_ebay_6 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_6);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_6 = jQuery(\"#fu_ebay_6\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Penrite Classic Car Coolant\",\nfu_ebay_query : \"Penrite Classic Car Coolant\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 6,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_6.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Best Cooling System Flush Product<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Before fitting a new radiator, the cooling system should be cleaned thoroughly.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Nulon Radiator Flush<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Removes scale<\/li>\n\n\n\n<li>Cleans cooling passages<\/li>\n\n\n\n<li>Improves coolant flow<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Preventative maintenance<\/li>\n\n\n\n<li>Cooling system upgrades<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A dirty engine block can quickly reduce the effectiveness of a new radiator.<\/p>\n\n\n<div id=\"fu_ebay_7\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 7 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_7\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Nulon Radiator Flush<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_7 = null;\nvar waitForDepends_fu_ebay_7 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_7);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_7 = jQuery(\"#fu_ebay_7\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Nulon Radiator Flush\",\nfu_ebay_query : \"Nulon Radiator Flush\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 7,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_7.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Common Radiator Upgrade Mistakes<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Replacing the Radiator Only<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Many cooling problems also involve:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Thermostat failure<\/li>\n\n\n\n<li>Water pump wear<\/li>\n\n\n\n<li>Blocked engine passages<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Ignoring Airflow<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A larger radiator cannot compensate for poor airflow.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Reusing Old Hoses<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">New radiators deserve new hoses.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Using Incorrect Coolant<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Coolant choice directly affects cooling performance and corrosion protection.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Recommended Cooling Upgrade Packages<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Budget Upgrade<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Radiator flush<\/li>\n\n\n\n<li>New thermostat<\/li>\n\n\n\n<li>New coolant<\/li>\n\n\n\n<li>New hoses<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Result<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Improved reliability at minimal cost.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Mid-Level Upgrade<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Triple-core radiator<\/li>\n\n\n\n<li>Water pump replacement<\/li>\n\n\n\n<li>New thermostat<\/li>\n\n\n\n<li>Fresh coolant<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Result<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Excellent cooling performance for most HR Holdens.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Ultimate Cooling Package<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Aluminium radiator<\/li>\n\n\n\n<li>Davies Craig electric fan<\/li>\n\n\n\n<li>New hoses<\/li>\n\n\n\n<li>Water pump<\/li>\n\n\n\n<li>Premium coolant<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Result<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Maximum reliability for touring and modified vehicles.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The HR Holden remains one of Australia&#8217;s most enjoyable classic cars, but its cooling system deserves careful attention. Many overheating issues stem from ageing radiators that are simply no longer capable of performing as intended. Whether you&#8217;re maintaining a stock 161-powered sedan or a modified 186-powered cruiser, a radiator upgrade is one of the most effective improvements you can make.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Products such as alloy radiators, Davies Craig fan kits, Dayco water pumps, Gates hoses and Penrite coolant can dramatically improve cooling performance and reduce the risk of overheating. For owners who regularly drive their HR Holden, upgrading the radiator is often one of the best investments available.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After all, nothing spoils a weekend cruise faster than watching the temperature gauge climb into the danger zone.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related Articles<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/hr-holden-cooling-system-problems\/\" type=\"post\" id=\"7270\">HR Holden Cooling System Problems<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/holden-186-engine-issues-explained\/\" type=\"post\" id=\"7268\">Holden 186 Engine Issues Explained<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/17\/holden-red-motor-cooling-system-problems\/\" type=\"post\" id=\"7234\">Holden Red Motor Cooling System Problems<\/a><\/li>\n\n\n\n<li>Best Coolants for Classic Holdens<\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/holden-red-engine-oil-leak-guide-2\/\" type=\"post\" id=\"7247\">Holden Red Engine Oil Leak Guide<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/hr-holden-rust-problems\/\" type=\"post\" id=\"7266\">HR Holden Rust Problems<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/16\/how-to-inspect-an-early-holden-before-buying\/\" type=\"post\" id=\"7193\">How to Inspect an Early Holden Before Buying<\/a><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The HR Holden is widely considered one of Holden&#8217;s finest achievements. Combining attractive styling, improved handling and the durable Red Motor engine family, the HR remains one of Australia&#8217;s most popular classic cars. Whether powered by a 161 or the highly sought-after 186 six-cylinder engine, the HR delivers a driving experience that still appeals to [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":581,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1],"tags":[],"class_list":["post-7272","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>HR Holden Radiator Upgrade Guide - Australian Holden<\/title>\n<meta name=\"description\" content=\"While the factory radiator was perfectly adequate when new, decades of corrosion, sediment build-up and increasing traffic conditions mean many HR Holdens now struggle to maintain ideal operating temperatures.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/hr-holden-radiator-upgrade-guide\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"HR Holden Radiator Upgrade Guide - Australian Holden\" \/>\n<meta property=\"og:description\" content=\"While the factory radiator was perfectly adequate when new, decades of corrosion, sediment build-up and increasing traffic 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