{"title":"Cummins 4-Stroke 170HP Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;max-width:980px;\"\u003e\n  \u003cp\u003e\n    This page supports Cummins 4‑Stroke 170 HP marine diesel engines and helps you find compatible parts and practical service information. Below you’ll find maintenance tips, frequently replaced components, and troubleshooting guidance. You can also browse our main Cummins-related parts categories, and at the bottom of the page you’ll find a quick way to start browsing parts for this engine. On collection pages, use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category.\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Cummins Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 170 HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eFind the engine dataplate: typically on the rocker cover, front gear housing, or starboard side of the block. Record the full engine serial number.\u003c\/li\u003e\n    \u003cli\u003eNote the CPL (Critical Parts List) if present. The CPL and serial number determine filter part numbers, belt sizes, seawater pump style, and other service components.\u003c\/li\u003e\n    \u003cli\u003eConfirm fuel system type: mechanical B‑series (6BT\/6BTA) vs. electronic common‑rail (QSB). Many 170 HP ratings are mechanical B‑series; parts differ by platform.\u003c\/li\u003e\n    \u003cli\u003eCheck marinization details (heat exchanger, aftercooler, seawater pump orientation) as these affect anodes, pump kits, and hose routing.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eEngine Platform Overview\u003c\/h2\u003e\n\n  \u003ch3\u003eCummins B‑Series 5.9 (6BT\/6BTA) — 170 HP\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInline‑6, 4‑stroke diesel, mechanical fuel system; heat‑exchanger cooled, seawater pump driven off front gear.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eOften labeled as 6BT5.9‑M or 6BTA5.9‑M (ratings vary by CPL\/marinization).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eProven durability, simple mechanical service, broad parts availability, excellent torque for cruising.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eMany filters and pump kits are CPL‑specific. Seawater pumps and anodes differ by heat‑exchanger\/aftercooler setup; verify by serial\/CPL.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eQSB Common‑Rail (5.9\/6.7) — General Reference\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInline‑6, 4‑stroke diesel with electronic common‑rail injection and ECU control.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eQSB5.9 or QSB6.7 marine variants. Ratings vary widely; some repowers may be detuned near 170 HP.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eRefined operation, strong mid‑range torque, improved fuel efficiency and diagnostics via ECU.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eFilters, sensors, and belts differ from mechanical B‑series. Always match parts by serial and calibration ID.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are common guidelines for marine diesels; always follow your official Cummins service manual and local operating conditions.\u003c\/p\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eUse marine‑grade diesel oil per spec; warm engine before draining for best results.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/oil-filters\"\u003eOil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003ePrimary\/secondary fuel filters\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 200 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eReplace both water‑separating (primary) and on‑engine (secondary) elements; prime system after service.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAir filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect 200 hours; replace as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCheck for restriction or salt spray contamination to prevent black smoke and power loss.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/air-filters\"\u003eAir Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eSeawater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 200 hours or 1–2 seasons\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eReplace earlier if stream weakens or after dry‑run\/overheat; inspect cam plate and cover.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/water-pumps\"\u003eWater pumps\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAnodes (HX\/aftercooler)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect every 3 months; replace as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eMatch anode material to water type (zinc—salt, aluminum—brackish, magnesium—fresh).\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eDrive belts\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eInspect 100 hours; replace if cracked\/glazed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCheck tension and alignment; squeal or low voltage may indicate belt slip.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/belt\"\u003eBelt\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n  \u003cp style=\"font-size:12px;color:#6b7280;\"\u003e*Intervals are typical guidelines; adjust based on hours, load, and environment.\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service: \u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\"\u003eService \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System Filtration: \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eEngine Lubrication: \u003ca href=\"https:\/\/seasierra.com\/collections\/oil-filters\"\u003eOil Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eAir Intake: \u003ca href=\"https:\/\/seasierra.com\/collections\/air-filters\"\u003eAir Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling \u0026amp; Seawater Pump: \u003ca href=\"https:\/\/seasierra.com\/collections\/water-pumps\"\u003eWater pumps\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection: \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eElectrical Starting: \u003ca href=\"https:\/\/seasierra.com\/collections\/starters\"\u003eStarters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eHoses \u0026amp; Clamps: \u003ca href=\"https:\/\/seasierra.com\/collections\/hoses\"\u003eHoses\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eOverheat alarm or weak discharge from exhaust\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect seawater strainer for debris, verify impeller condition, check belt tension to circulation pump, confirm intake screen is clear.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eWater pump kit\/impeller, thermostat, intake screen, hoses, anodes.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003ePoor acceleration or low WOT RPM\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eReplace fuel filters, check for air restriction, verify throttle linkage; if turbocharged, inspect charge‑air hoses for leaks.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eFuel filters, air filter, hoses, belts.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eConfirm battery voltage, prime\/bleed fuel system, check lift pump output, inspect for fuel leaks or air intrusion.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eFuel filters, hoses, starter.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eExcessive black smoke\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCheck propeller load, air filter restriction, soot\/salt in exhaust elbow, and fuel injector condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAir filter, exhaust elbows, injectors, propeller.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eRapid anode consumption or rusty water in HX\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eVerify correct anode material, check for stray current corrosion, and inspect bonding\/grounds.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eAnodes, hoses, sensors\/grounds.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"faq\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eNot reliably. Cummins parts are tied to the engine serial number and CPL. Mechanical 6BT\/6BTA and electronic QSB engines often use different filters, belts, pumps, and sensors. Verify by serial\/CPL before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the seawater pump impeller?\u003c\/summary\u003e\n    \u003cp\u003eEvery 200 hours or 1–2 seasons is typical, sooner if the pump is run dry, debris is found in the strainer, or discharge weakens. Always inspect the cam plate and cover for scoring.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should fuel and engine oil filters be changed?\u003c\/summary\u003e\n    \u003cp\u003eOil and filter are commonly serviced every 100 hours or annually. Fuel filters are commonly replaced every 200 hours or annually, or immediately if water\/contamination is detected.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information do you need to confirm compatibility?\u003c\/summary\u003e\n    \u003cp\u003ePlease provide the engine serial number, CPL, fuel system type (mechanical vs. common‑rail), and details of the marinization (heat exchanger\/aftercooler). Photos of the dataplate and the part you are replacing are very helpful.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;max-width:980px;\"\u003e\n  \u003cp\u003eReady to find parts by category and narrow by your engine’s details? Browse our main collection and use Filter \u0026amp; Sort to refine by part type.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Cummins Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n  \u003cp style=\"font-size:12px;color:#6b7280;\"\u003eIf you’re unsure about your model, send us a photo of the nameplate and the part you need and we’ll help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[],"url":"https:\/\/seasierra.com\/collections\/cummins-4-stroke-170hp-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}