{"id":4439,"date":"2026-10-26T07:05:34","date_gmt":"2026-10-26T07:05:34","guid":{"rendered":"https:\/\/www.hongtengdaparts.com\/product\/caterpillar-587-1312-fan-pump-350\/"},"modified":"2026-10-26T07:05:34","modified_gmt":"2026-10-26T07:05:34","slug":"caterpillar-587-1312-fan-pump-350","status":"publish","type":"product","link":"https:\/\/www.hongtengdaparts.com\/pt\/product\/caterpillar-587-1312-fan-pump-350\/","title":{"rendered":"587-1312 Piston Pump for CAT 350 Excavator, Variable Displacement"},"content":{"rendered":"<p>Most of our pages can quote Caterpillar&#8217;s applicability list for a part. This one cannot, and rather than fill the gap with supplier copy we are going to show you exactly where the evidence stops and what to do about it. That is a more useful page for a purchasing officer than a confident guess.<\/p>\n<h2>What is established<\/h2>\n<p>Caterpillar lists 587-1312 as <strong>PUMP GP-PS-B<\/strong>. That suffix is not decorative: the same PS-B designation appears on other Cat pump listings whose full descriptions read variable displacement axial piston pump, so the type is settled. The physical unit in our photographs carries a plate reading PISTON PUMP, CNR 587-1312, serial 5790442, with a regulator block and solenoid on top and a splined input shaft.<\/p>\n<h2>What is not established, and what we will not claim<\/h2>\n<ul>\n<li><strong>Cat&#8217;s machine applicability for this number.<\/strong> We could not retrieve a first-party applicability list. Everything naming a machine for 587-1312 comes from aftermarket sellers.<\/li>\n<li><strong>The 352.<\/strong> Our own source data listed 350 and 352. The 352 claim is unsupported, and Cat&#8217;s data for the 352 points at a different pump, 524-0924. We have dropped 352 from this page.<\/li>\n<li><strong>That it is the fan pump.<\/strong> The trade sells it as a fan pump and the physical arrangement is consistent with that role on this platform, but Cat&#8217;s title does not use the word fan. Treat the function as confirmed by your parts book, not by us.<\/li>\n<li><strong>Any displacement, pressure or flow figure.<\/strong> None is published for this number. If a listing quotes one, ask for the source.<\/li>\n<\/ul>\n<h2>How to confirm fitment in ten minutes<\/h2>\n<ol>\n<li>Read the number off the plate of the pump already on the machine. This outranks every catalogue, including ours.<\/li>\n<li>Note the machine serial prefix, the first three characters of the serial number, and the engine model from the data plate.<\/li>\n<li>Look the number up against that prefix in Cat&#8217;s parts catalogue, or ask your dealer parts desk for the applicability and any supersession history. Cat&#8217;s own guidance is that parts are listed as designed to fit on the manufacturer&#8217;s specifications and that you should consult a dealer before purchasing.<\/li>\n<li>Send us the plate photograph and the prefix. We will quote against what you have rather than against a model badge.<\/li>\n<\/ol>\n<h2>Machine context for the platform<\/h2>\n<p>Caterpillar lists the 350 as a current model in its excavator range alongside the 352, and publishes first-party data for the 352 of the same generation: net power of 330 kW (443 hp) to ISO 9249 from a C13, operating weight around 50,600 kg, high-ambient working capability of 52 C, standard cold start at \u221218 C and altitude capability to 4,500 m without de-rating. The same page describes the cooling arrangement in terms worth reading carefully before you blame a pump:<\/p>\n<blockquote><p>The high-efficiency hydraulic fan has a programmable automatic reverse function to clear debris from the cores without operator intervention.<\/p><\/blockquote>\n<p>A fan that reverses on a program is a fan whose pump is being commanded continuously. When cooling complaints appear on these machines, the command path fails at least as often as the pump does.<\/p>\n<h2>Diagnosis before replacement<\/h2>\n<p>Work in this order: command and signal, then delivery and pressure, then the unit. Our <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/diagnostico-da-bomba-do-ventilador-hidraulico-da-escavadeira\/\">hydraulic fan pump diagnosis guide<\/a> covers flow and pressure testing, <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/diagnostico-e-ajuste-do-regulador-da-bomba-principal-da-escavadeira\/\">the regulator article<\/a> covers the control signal, and <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/teste-do-sensor-de-temperatura-do-liquido-de-arrefecimento-da-escavadeira\/\">coolant sensor testing<\/a> is the cheapest check on the list. If the machine also lost drive train oil, read <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/diagnostico-de-falha-da-caixa-de-transferencia-da-bomba-da-escavadeira\/\">the transfer case failure guide<\/a> before assuming the pump failed on its own.<\/p>\n<h2>Fitting<\/h2>\n<p>Match shaft spline, pilot, flange, port positions and control orientation against the removed pump. Prime the casing with clean oil before cranking. Fit a new return filter element and clear the suction strainer. Keep the case drain unrestricted to tank. Hold cleanliness around ISO 4406 18\/16\/13, the class Bosch Rexroth guidance gives for axial piston units. Prove full fan speed under thermal load and log both temperatures.<\/p>\n<h2>Terms<\/h2>\n<p>Minimum order one piece. New aftermarket units carry a three to six month warranty as stated on your proforma invoice. Bench tested, photographed against your order before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. If you need certainty on fitment before we ship, we will hold the order until your dealer confirms the prefix. Related: <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/produto\/caterpillar-505-5180-fan-motor-349gc\/\">505-5180 fan motor<\/a> and the full <a href=\"https:\/\/www.hongtengdaparts.com\/pt\/categoria-produto\/motor-do-ventilador-hidraulico\/caterpillar-fan-motor\/\">Caterpillar range<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p><strong>Part:<\/strong> 587-1312 piston pump, listed by Caterpillar as PUMP GP-PS-B, a variable displacement axial piston unit. The unit we photograph carries a plate reading piston pump, CNR 587-1312.<\/p>\n<p><strong>Trade fitment:<\/strong> 349 GC, 350 and 350 mobile hydraulic power unit. Caterpillar&#8217;s own applicability data for this number could not be verified, and we say so below rather than inventing a fitment list.<\/p>\n<p><strong>Supplied as:<\/strong> new HTD-brand replacement, made in China. MOQ 1 piece, wooden case, dispatch 5 to 8 working days.<\/p>","protected":false},"featured_media":4403,"template":"","meta":[],"product_brand":[],"product_cat":[599,37],"product_tag":[651,652,54,643],"class_list":["post-4439","product","type-product","status-publish","has-post-thumbnail","product_cat-caterpillar-fan-motor","product_cat-hydraulic-fan-motor","product_tag-587-1312","product_tag-cat-350","product_tag-caterpillar","product_tag-piston-pump","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/product\/4439","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/media\/4403"}],"wp:attachment":[{"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/media?parent=4439"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/product_brand?post=4439"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/product_cat?post=4439"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/pt\/wp-json\/wp\/v2\/product_tag?post=4439"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}