{"id":2523,"date":"2026-06-15T07:34:49","date_gmt":"2026-06-15T07:34:49","guid":{"rendered":"https:\/\/www.hongtengdaparts.com\/?post_type=product&p=2523"},"modified":"2026-06-15T07:34:49","modified_gmt":"2026-06-15T07:34:49","slug":"hitachi-ex400-ex400-1-hydraulic-main-pump","status":"publish","type":"product","link":"https:\/\/www.hongtengdaparts.com\/nl\/product\/hitachi-ex400-ex400-1-hydraulic-main-pump\/","title":{"rendered":"Hitachi EX400 \/ EX400-1 Hydraulische Hoofdpomp \u2013 In China Gereviseerd (4622371 \/ 4246412)"},"content":{"rendered":"

Detail Informatie<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nWaarde<\/th>\nOpmerking<\/th>\n<\/tr>\n
Herkomst<\/b><\/td>\nChina<\/td>\nGereviseerd<\/td>\n<\/tr>\n
Garantie<\/b><\/td>\n3-6 maanden afhankelijk van productspecificaties; Wij verlenen geen garantie op originele en gebruikte producten.<\/td>\n\u2013<\/td>\n<\/tr>\n
Minimale bestelhoeveelheid<\/b><\/td>\n1 stuk<\/td>\n\u2013<\/td>\n<\/tr>\n
Monthly Output<\/b><\/td>\n300 stuks\/maand<\/td>\n\u2013<\/td>\n<\/tr>\n
Verpakkingsgegevens<\/b><\/td>\nHouten kistverpakking of maatwerk<\/td>\n\u2013<\/td>\n<\/tr>\n
Betalingsvoorwaarden<\/b><\/td>\nT\/T, XT, PayPal, Western Union<\/td>\n\u2013<\/td>\n<\/tr>\n
Levertijd<\/b><\/td>\n5-8 werkdagen (afhankelijk van de ordersituatie)<\/td>\n\u2013<\/td>\n<\/tr>\n
Verzendmethode<\/b><\/td>\nZeevracht, luchtvracht of via DHL\/FEDEX\/TNT\/EMS<\/td>\n\u2013<\/td>\n<\/tr>\n
Guarantee Measures<\/b><\/td>\nWij inspecteren het product en sturen gedetailleerde foto's naar de koper ter bevestiging.<\/td>\n\u2013<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The 40\u2011Ton Dilemma: Repair, Replace, or Gamble?<\/span><\/h3>\n

You have an EX400 or EX400\u20111 that has lost its edge. The boom rises slower than it used to. The swing hesitates. The oil runs hot. The mechanic says \u201cthe pump is tired.\u201d Now you face the same decision every owner of an older 40\u2011ton machine faces:<\/span><\/p>\n

    \n
  • \n

    Buy new genuine<\/span><\/strong>\u00a0\u2013 Safe, but the price tag could buy a small car. Hard to justify on a machine that already has 10,000+ hours.<\/span><\/p>\n<\/li>\n

  • \n

    Buy a used pump<\/span><\/strong>\u00a0\u2013 Cheap upfront, but you have no idea how many hours are on it, whether it was run with contaminated oil, or if its bearings are already pitting. You are buying someone else\u2018s hidden failure.<\/span><\/p>\n<\/li>\n

  • \n

    Send your pump for \u201crepair\u201d<\/span><\/strong>\u00a0\u2013 Usually means a set of seals and paint. It will leak again in 500 hours.<\/span><\/p>\n<\/li>\n

  • \n

    Choose a proper remanufactured pump<\/span><\/strong>\u00a0\u2013 This is where the smart money goes. But only if the reman process actually replaces the right parts.<\/span><\/p>\n<\/li>\n<\/ul>\n

    Let\u2019s talk about what \u201cremanufactured\u201d actually means \u2013 and why most shops get it wrong.<\/span><\/strong><\/p>\n

    The Myth of \u201cRe\u2011sealed\u201d<\/span><\/h3>\n

    Many hydraulic shops offer \u201crebuilt\u201d pumps. They disassemble, clean, replace O\u2011rings and shaft seals, slap on new paint, and call it done. The problem? The cylinder block and valve plate are still worn. The bearings are still fatigued. The piston slippers are still scored. Within 500\u20131,000 hours, internal leakage returns, oil temperature climbs, and you lose power again. You paid for a band\u2011aid, not a fix.<\/span><\/p>\n

    Our remanufacturing process is different because we start from a simple truth: worn metal does not un\u2011wear itself. You must replace it.<\/span><\/strong><\/p>\n

    What We Actually Replace (Not Just Clean)<\/span><\/h3>\n

    When we remanufacture your EX400\/EX400\u20111 pump (OEM 4622371 \/ 4246412), every single one of these components is inspected and almost always replaced:<\/span><\/p>\n

    \n\n\n\n\n\n\n\n\n\n\n\n
    Onderdeel<\/span><\/th>\nWhy It Fails<\/span><\/th>\nWat we doen<\/span><\/th>\n<\/tr>\n<\/thead>\n
    Cylinder block<\/span><\/td>\nScoring from contaminated oil<\/span><\/td>\nRe\u2011grind or replace<\/span><\/td>\n<\/tr>\n
    Valve plate<\/span><\/td>\nWear grooves, loss of flatness<\/span><\/td>\nSurface grind to <0.002mm flatness<\/span><\/td>\n<\/tr>\n
    Piston assemblies<\/span><\/td>\nSlipper wear, cylinder bore scoring<\/span><\/td>\nReplace as matched set<\/span><\/td>\n<\/tr>\n
    Swashplate<\/span><\/td>\nGrooving from piston shoes<\/span><\/td>\nRecondition or replace<\/span><\/td>\n<\/tr>\n
    Bearings (all)<\/span><\/td>\nFatigue cracks from load cycles<\/span><\/td>\nAlways new \u2013 never reused<\/span><\/td>\n<\/tr>\n
    Shaft seal<\/span><\/td>\nHardening, lip wear<\/span><\/td>\nNew (fluororubber, high\u2011temp)<\/span><\/td>\n<\/tr>\n
    All O\u2011rings and gaskets<\/span><\/td>\nCompression set, chemical degradation<\/span><\/td>\nNew<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

    That is a full restoration, not a cosmetic refresh.<\/span><\/strong><\/p>\n

    The Real Test: Not a Spinning Shaft, But a Loaded Dyno Run<\/span><\/h3>\n

    Any pump can turn by hand. A proper reman pump must prove itself under full working pressure. After reassembly, every EX400 pump we reman goes onto a hydraulic test stand and runs through a complete test cycle:<\/span><\/p>\n

      \n
    • \n

      Pressure ramp to 34.3 MPa (4,975 psi)<\/span><\/p>\n<\/li>\n

    • \n

      Flow measurement at rated speed<\/span><\/p>\n<\/li>\n

    • \n

      Case drain leakage check (internal wear indicator)<\/span><\/p>\n<\/li>\n

    • \n

      Load\u2011sensing response time<\/span><\/p>\n<\/li>\n

    • \n

      Pressure cut\u2011off verification<\/span><\/p>\n<\/li>\n<\/ul>\n

      You get a test report with actual numbers. No guessing. No \u201cfeels strong.\u201d You see the data before you pay.<\/span><\/p>\n

      Why This Matters for Your EX400 \/ EX400\u20111<\/span><\/h3>\n

      Your machine weighs 40 tons. It moves thousands of cubic meters of material every day. When the main pump loses just 10% of its efficiency, you lose:<\/span><\/p>\n

        \n
      • \n

        10\u201315% in cycle time<\/span><\/strong>\u00a0\u2013 slower loading, fewer trucks per hour<\/span><\/p>\n<\/li>\n

      • \n

        Higher fuel burn<\/span><\/strong>\u00a0\u2013 the engine works harder to compensate for internal leakage<\/span><\/p>\n<\/li>\n

      • \n

        Overheated oil<\/span><\/strong>\u00a0\u2013 wasted energy turns into heat, cooking seals and hoses<\/span><\/p>\n<\/li>\n

      • \n

        Unpredictable failures<\/span><\/strong>\u00a0\u2013 a tired pump does not die slowly; it fails suddenly<\/span><\/p>\n<\/li>\n<\/ul>\n

        A proper reman pump restores original flow, pressure, and efficiency. Your EX400 digs like it did 8,000 hours ago. Not \u201calmost.\u201d Not \u201cgood enough.\u201d Exactly.<\/span><\/p>\n

        The Simple Offer<\/span><\/h3>\n

        We keep remanufactured EX400\/EX400\u20111 pumps (4622371 \/ 4246412) on the shelf in our Guangzhou warehouse. Not a core that we hope to rebuild next month. A finished unit, tested, painted, capped, and ready to bolt on.<\/span><\/p>\n

        What you get:<\/span><\/strong><\/p>\n

          \n
        • \n

          A pump restored to OEM performance standards<\/span><\/p>\n<\/li>\n

        • \n

          New bearings, new seals, re\u2011ground wear surfaces<\/span><\/p>\n<\/li>\n

        • \n

          Hydraulic test report upon request<\/span><\/p>\n<\/li>\n

        • \n

          Heavy\u2011duty wooden case, fumigation\u2011free, export ready<\/span><\/p>\n<\/li>\n

        • \n

          5\u20138 working days to most global destinations<\/span><\/p>\n<\/li>\n<\/ul>\n

          What you do not get:<\/span><\/strong><\/p>\n

            \n
          • \n

            A used pump with fresh paint<\/span><\/p>\n<\/li>\n

          • \n

            \u201cAs\u2011is\u201d gamble<\/span><\/p>\n<\/li>\n

          • \n

            A 500\u2011hour band\u2011aid<\/span><\/p>\n<\/li>\n<\/ul>\n

            Voordat u bestelt \u2013 \u00e9\u00e9n foto, \u00e9\u00e9n serienummer<\/span><\/h3>\n

            Because EX400 and EX400\u20111 have minor variations (different regulator settings, different port orientations), we need two things from you:<\/span><\/p>\n

              \n
            1. \n

              Machineserienummer<\/span><\/strong>\u00a0(starts with EX400 or EX400\u20111)<\/span><\/p>\n<\/li>\n

            2. \n

              A clear photo of the old pump\u2019s nameplate<\/span><\/strong>\u00a0(showing the OEM part number, even if faded)<\/span><\/p>\n<\/li>\n<\/ol>\n

              We will confirm exact fitment and send you a firm quote within 24 hours. No guesswork. No \u201cthis should fit.\u201d<\/span><\/p>\n

              \n
              \n

              Installation in plain language:<\/span><\/strong>
              \n\u2013 The small drain line from the pump to the tank must be open. If it is pinched or blocked, pressure will build inside the pump and blow the main shaft seal the first time you start the engine.<\/span>
              \n\u2013 Before you bolt the new pump on, change all hydraulic filters and flush the tank if the old pump failed catastrophically (metal in oil). Debris kills a reman pump just as fast as a new one.<\/span>
              \n\u2013 Use new copper washers or O\u2011rings on every hose connection. Old seals will leak.<\/span>
              \n\u2013 After installation, idle the engine for a few minutes and slowly move each lever (boom, arm, bucket, swing, travel) to get the air out of the system. The machine may be sluggish at first \u2013 that is normal.<\/span><\/p>\n<\/blockquote>\n

              \n

              Warranty \u2013 honest and upfront:<\/span><\/strong>
              \nGarantieperiode is 3 tot 6 maanden afhankelijk van productspecificaties.\u00a0<\/span>We do not provide warranty for original used or remanufactured parts.<\/span><\/strong>\u00a0We believe in doing the job right before we ship, not promising to fix it later. Our value is in the work \u2013 new parts, precise assembly, full testing, and photos before dispatch. If you need a traditional warranty, ask us about new aftermarket options.<\/span><\/p>\n<\/blockquote>\n

              Your EX400 or EX400\u20111 has years of work left in it. The main pump should not be the reason you park it. Send us your machine details \u2013 we will get you a reman pump that actually works.<\/span><\/strong><\/p>","protected":false},"excerpt":{"rendered":"\n\n\n\n\n\n\n\n\n
              Parameter<\/th>\nWaarde<\/th>\n<\/tr>\n
              Toepasselijk model<\/b>}]<\/td>\nEX400, EX400-1<\/td>\n<\/tr>\n
              Productnaam<\/b><\/td>\nHitachi Hydraulische Pomp<\/td>\n<\/tr>\n
              Onderdeelnummers<\/b><\/td>\n4622371, 4246412<\/td>\n<\/tr>\n
              Product Type<\/b><\/td>\nHydrauliekpomp<\/td>\n<\/tr>\n
              Categorie<\/b><\/td>\nHydraulisch Systeem<\/td>\n<\/tr>\n
              Merk<\/b><\/td>\nHTD<\/td>\n<\/tr>\n<\/tbody>\n<\/table>","protected":false},"featured_media":2527,"template":"","meta":[],"product_brand":[],"product_cat":[68],"product_tag":[],"class_list":["post-2523","product","type-product","status-publish","has-post-thumbnail","product_cat-hitachi-hydraulic-pump","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/product\/2523","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/media\/2527"}],"wp:attachment":[{"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/media?parent=2523"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/product_brand?post=2523"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/product_cat?post=2523"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.hongtengdaparts.com\/nl\/wp-json\/wp\/v2\/product_tag?post=2523"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}