{"id":721,"date":"2017-12-14T13:13:53","date_gmt":"2017-12-14T21:13:53","guid":{"rendered":"http:\/\/loggersretreat.com\/rebuild\/?p=721"},"modified":"2017-12-14T13:20:48","modified_gmt":"2017-12-14T21:20:48","slug":"and-a-glowing-report","status":"publish","type":"post","link":"https:\/\/loggersretreat.com\/rebuild\/2017\/12\/14\/and-a-glowing-report\/","title":{"rendered":"And a Glowing Report"},"content":{"rendered":"<p>At the end of my &#8220;Clearance: Half Off&#8221; post I mentioned that we still had a problem with the Bobcat: its glowplugs were not working.<\/p>\n<p>Unlike gasoline engines, Diesels do not have spark plugs.\u00a0 To ignite their fuel they use the fact that the temperature of any gas will increase as you compress it. The piston compresses air inside a cylinder until it is hot enough to ignite diesel fuel.\u00a0 Then at the proper time the engine injects fuel into the cylinder to ignite it, which then drives the piston back down.<\/p>\n<p>But this only works if the temperature inside the cylinder gets hot enough to ignite diesel fuel.\u00a0 If the engine is too cold a diesel engine can&#8217;t start without some help.\u00a0 This is what glowplugs are for.<\/p>\n<p>A glowplug is essentially a small electric heater installed at the top of the cylinder.\u00a0 When the engine is cold the glowplug will heat the air in the cylinder enough to ignite the fuel.\u00a0 Once the engine is running and warm, the additional heat is not needed.\u00a0 So glowplugs are only needed when the engine is cold.<\/p>\n<p>When it got cold enough outside, our Bobcat started warning us that the glowplugs were not working right.\u00a0 And sure enough: the colder it got outside, the more difficult it was to start the Bobcat.<\/p>\n<p>Now remember, the main reason we need the Bobcat is to clear snow from the driveway. So a glowplug warning in cool weather is quite likely to become a show-stopper in cold, snowy weather, right when we need the Bobcat most.\u00a0 This was a problem that we needed to fix <strong>before<\/strong> we got snow.<\/p>\n<p>Fortunately, glowplugs are pretty simple devices. And a quick review of the Bobcat wiring diagram confirmed that the circuit was pretty simple too.\u00a0 The problem had to be either a bad glowplug or a bad relay.\u00a0 And since there is one glowplug for each cylinder, the Bobcat would likely still start easily if only one glowplug were bad.\u00a0 So it would seem that either all glowplugs had failed (not likely) or something common to all glowplugs had failed (much more likely).<\/p>\n<p>The only thing common to all glowplugs is the relay, which supplies power to them when it is cold out.\u00a0 The relay is located in the Bobcat&#8217;s fuse box, plugged into a socket there.<\/p>\n<figure id=\"attachment_671\" aria-describedby=\"caption-attachment-671\" style=\"width: 400px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-671\" src=\"http:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/FuseboxOpen-400x300.jpg\" alt=\"\" width=\"400\" height=\"300\" srcset=\"https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/FuseboxOpen-400x300.jpg 400w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/FuseboxOpen-200x150.jpg 200w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/FuseboxOpen-768x576.jpg 768w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/FuseboxOpen-800x600.jpg 800w\" sizes=\"auto, (max-width: 400px) 100vw, 400px\" \/><figcaption id=\"caption-attachment-671\" class=\"wp-caption-text\">The Bobcat&#8217;s fusebox, with relays installed<\/figcaption><\/figure>\n<p>So our problem could be that the relay was bad, or there was a bad connection in the relay socket.<\/p>\n<p>Last weekend I finally had the chance to investigate on-site.\u00a0 I quickly proved that it was the glowplug relay itself by swapping the relay with another, known-good relay nearby.<\/p>\n<p>No more flashing warning light, and the Bobcat fired right up.\u00a0 Victory!<\/p>\n<p>I could have just left it at that, with the relays swapped. (The known-good relay had controlled the rear floodlights.)\u00a0 But I noticed that it was possible to pop off the relay cover and peek inside.\u00a0 This is what that looks like.<\/p>\n<figure id=\"attachment_670\" aria-describedby=\"caption-attachment-670\" style=\"width: 400px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-670 size-medium\" src=\"http:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/RelayExposed-400x300.jpg\" alt=\"Image of a relay and its cover in the sunlight\" width=\"400\" height=\"300\" srcset=\"https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/RelayExposed-400x300.jpg 400w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/RelayExposed-200x150.jpg 200w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/RelayExposed-768x576.jpg 768w, https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/12\/RelayExposed-800x600.jpg 800w\" sizes=\"auto, (max-width: 400px) 100vw, 400px\" \/><figcaption id=\"caption-attachment-670\" class=\"wp-caption-text\">The relay and cover separated.<\/figcaption><\/figure>\n<p>It was pretty clear that the relay had gotten wet; it was dirty and corroded inside.\u00a0 But mechanically it still seemed to work.\u00a0 So I spent a few minutes cleaning it, blowing out the dirt and exercising the mechanism.<\/p>\n<p>After that, poking around with a volt-ohm meter suggested that it was working again.\u00a0 So I snapped the cover back on and tried it in the Bobcat. Joy ensued.<\/p>\n<p>Now I have working glowplugs<strong> and<\/strong> rear floodlights.\u00a0 Bring on the snow!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>At the end of my &#8220;Clearance: Half Off&#8221; post I mentioned that we still had a problem with the Bobcat: its glowplugs were not working. Unlike gasoline engines, Diesels do not have spark plugs.\u00a0 To ignite their fuel they use the fact that the temperature of any gas will increase as you compress it. The &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/loggersretreat.com\/rebuild\/2017\/12\/14\/and-a-glowing-report\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;And a Glowing Report&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":451,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"status","meta":{"_crdt_document":"","jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1],"tags":[],"class_list":["post-721","post","type-post","status-publish","format-status","has-post-thumbnail","hentry","category-uncategorized","post_format-post-format-status"],"jetpack_publicize_connections":[],"cc_featured_image_caption":{"caption_text":"The Bobcat's fusebox and its relays are conveniently located below the seat","source_text":"","source_url":""},"jetpack_featured_media_url":"https:\/\/loggersretreat.com\/rebuild\/wp-content\/uploads\/2017\/10\/S185FuseboxLocation.png","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p9iwY6-bD","_links":{"self":[{"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/posts\/721","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/comments?post=721"}],"version-history":[{"count":9,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/posts\/721\/revisions"}],"predecessor-version":[{"id":731,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/posts\/721\/revisions\/731"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/media\/451"}],"wp:attachment":[{"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/media?parent=721"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/categories?post=721"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/loggersretreat.com\/rebuild\/wp-json\/wp\/v2\/tags?post=721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}