{"id":7270,"date":"2026-06-20T10:08:51","date_gmt":"2026-06-20T10:08:51","guid":{"rendered":"http:\/\/australianholden.com\/?p=7270"},"modified":"2026-06-22T10:39:44","modified_gmt":"2026-06-22T10:39:44","slug":"hr-holden-cooling-system-problems","status":"publish","type":"post","link":"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/hr-holden-cooling-system-problems\/","title":{"rendered":"HR Holden Cooling System Problems"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The HR Holden is one of the most beloved vehicles ever produced by Holden. Introduced in 1966, it brought improved styling, better handling and the increasingly popular Red Motor engine range to Australian families. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, as these cars approach sixty years of age, cooling system problems have become one of the most common issues affecting surviving examples. Overheating, coolant leaks, blocked radiators and worn water pumps are now frequent concerns for owners. While the original cooling system was more than adequate when new, decades of corrosion, sediment build-up and component wear can significantly reduce its effectiveness.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fortunately, most cooling system problems are easy to diagnose and relatively straightforward to repair.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Understanding the HR Holden Cooling System<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The HR Holden used a simple and effective cooling system design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Major Components<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Belt-driven water pump<\/li>\n\n\n\n<li>Crossflow radiator<\/li>\n\n\n\n<li>Mechanical cooling fan<\/li>\n\n\n\n<li>Thermostat<\/li>\n\n\n\n<li>Upper and lower radiator hoses<\/li>\n\n\n\n<li>Heater core<\/li>\n\n\n\n<li>Engine water jackets<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">When functioning correctly, the system is capable of keeping even a 186 Red Motor operating comfortably in Australian conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The challenge today is that many components are several decades beyond their original service life.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Overheating Problems<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Overheating is by far the most common cooling system complaint among HR Holden owners.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Temperature gauge running high<\/li>\n\n\n\n<li>Steam from engine bay<\/li>\n\n\n\n<li>Coolant loss<\/li>\n\n\n\n<li>Engine pinging<\/li>\n\n\n\n<li>Reduced performance<\/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<\/li>\n\n\n\n<li>Worn water pump<\/li>\n\n\n\n<li>Faulty thermostat<\/li>\n\n\n\n<li>Internal engine corrosion<\/li>\n\n\n\n<li>Restricted coolant flow<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Many overheating issues are caused by multiple contributing factors rather than a single fault.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Blocked Radiators<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The original radiator is often the first component to cause cooling problems.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Why It Happens<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Over decades, rust, scale and sediment accumulate inside the radiator core.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This restricts coolant flow and reduces cooling efficiency.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Overheating at highway speeds<\/li>\n\n\n\n<li>Temperature fluctuations<\/li>\n\n\n\n<li>Cool spots across radiator core<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Professional radiator testing can quickly identify internal restrictions.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Radiator Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Alloy Performance Radiator<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Improved cooling capacity<\/li>\n\n\n\n<li>Lightweight construction<\/li>\n\n\n\n<li>Better heat transfer<\/li>\n\n\n\n<li>Increased reliability<\/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>Warm climates<\/li>\n\n\n\n<li>Touring vehicles<\/li>\n\n\n\n<li>Modified Red Motors<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Modern alloy radiators provide a substantial improvement over ageing factory units.<\/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;HR Holden alloy 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 : \"HR Holden alloy radiator\",\nfu_ebay_query : \"HR Holden alloy 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\">Water Pump Failure<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The water pump is responsible for circulating coolant throughout the engine.<\/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>Bearing noise<\/li>\n\n\n\n<li>Overheating<\/li>\n\n\n\n<li>Coolant circulation problems<\/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>Bearing wear<\/li>\n\n\n\n<li>Seal failure<\/li>\n\n\n\n<li>Corrosion<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Most original pumps have been replaced at least once during the vehicle&#8217;s life.<\/p>\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>Reliable coolant circulation<\/li>\n\n\n\n<li>Quality bearings<\/li>\n\n\n\n<li>Direct fitment<\/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>Standard engines<\/li>\n\n\n\n<li>Rebuilt engines<\/li>\n\n\n\n<li>Preventative maintenance<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Replacing an ageing water pump is often inexpensive insurance against future problems.<\/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;Dayco HR Holden water pump<\/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 : \"Dayco HR Holden water pump\",\nfu_ebay_query : \"Dayco 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 : 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\">Thermostat Problems<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The thermostat controls engine operating temperature.<\/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>Slow warm-up<\/li>\n\n\n\n<li>Temperature fluctuations<\/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>Thermostat sticking closed<\/li>\n\n\n\n<li>Internal corrosion<\/li>\n\n\n\n<li>Age-related failure<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A faulty thermostat can quickly cause overheating.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fortunately, replacement is inexpensive and straightforward.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Thermostat Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Tridon Thermostat<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Reliable operation<\/li>\n\n\n\n<li>Consistent temperatures<\/li>\n\n\n\n<li>High-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>Routine maintenance<\/li>\n\n\n\n<li>Cooling system rebuilds<\/li>\n<\/ul>\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;Tridon<\/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 : \"Tridon\",\nfu_ebay_query : \"HR Holden Tridon thermostat\",\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\">Internal Engine Corrosion<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Many HR Holden engines have spent decades running poor-quality coolant or plain water.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Chronic overheating<\/li>\n\n\n\n<li>Rust-coloured coolant<\/li>\n\n\n\n<li>Blocked cooling passages<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Why It Happens<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Internal rust gradually reduces coolant flow through the block and cylinder head.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The problem is particularly common in engines that have sat unused for long periods.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Coolant Leaks<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Coolant leaks are another frequent issue.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Common Leak Locations<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Radiator tanks<\/li>\n\n\n\n<li>Hose connections<\/li>\n\n\n\n<li>Heater hoses<\/li>\n\n\n\n<li>Water pump<\/li>\n\n\n\n<li>Core plugs<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Coolant smell<\/li>\n\n\n\n<li>Wet engine bay<\/li>\n\n\n\n<li>Falling coolant level<\/li>\n\n\n\n<li>Overheating<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Leaks should be repaired promptly to prevent major engine damage.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Hose Deterioration<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Rubber hoses naturally degrade with age.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Symptoms<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Soft hoses<\/li>\n\n\n\n<li>Cracks<\/li>\n\n\n\n<li>Bulging sections<\/li>\n\n\n\n<li>Coolant seepage<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Why It Happens<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Heat cycles gradually weaken rubber compounds.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Many HR Holdens still contain hoses that are decades old.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Cooling Hose Upgrade<\/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>Improved durability<\/li>\n\n\n\n<li>High-quality rubber construction<\/li>\n\n\n\n<li>Reliable fitment<\/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>Preventative maintenance<\/li>\n\n\n\n<li>Long-distance touring<\/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<\/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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Overheating, coolant leaks, blocked radiators and water pump failures are among the most common issues owners encounter today.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fortunately, modern replacement parts and upgrades can dramatically improve reliability. Products such as Dayco water pumps, Gates hose kits, Tridon thermostats, Penrite coolant and Davies Craig electric fans help ensure these classic Holdens remain enjoyable to drive in modern Australian conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Whether you&#8217;re restoring a factory-original HR Special or building a dependable weekend cruiser, maintaining the cooling system should be one of your highest priorities. Few mechanical problems can damage a classic Holden faster than an overheating engine.<\/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\/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><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-transmission-problems\/\" type=\"post\" id=\"7274\">HR Holden Transmission Problems<\/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\/20\/hd-holden-electrical-problems\/\" type=\"post\" id=\"7264\">HD Holden Electrical Problems<\/a><\/li>\n\n\n\n<li>Best Coolants for Classic Holdens<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The HR Holden is one of the most beloved vehicles ever produced by Holden. Introduced in 1966, it brought improved styling, better handling and the increasingly popular Red Motor engine range to Australian families. However, as these cars approach sixty years of age, cooling system problems have become one of the most common issues affecting [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3567,"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-7270","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 - 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\/>\n<meta property=\"og:site_name\" content=\"Australian Holden\" \/>\n<meta property=\"article:published_time\" content=\"2026-06-20T10:08:51+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-06-22T10:39:44+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/uploads\/2026\/04\/HR-Holden.png?fit=1024%2C680&ssl=1\" \/>\n\t<meta property=\"og:image:width\" content=\"1024\" \/>\n\t<meta property=\"og:image:height\" content=\"680\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Administrator\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Administrator\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutes\" \/>\n<script type=\"application\/ld+json\" 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