{"product_id":"volvo-932","title":"Volvo Penta Belt Tensioner 421540 | TAMD TD TWD TAD Diesel","description":"\u003ch2\u003eVolvo Penta Belt Tensioner 421540 | TAMD TD TWD TAD Diesel\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003ePart Number:\u003c\/strong\u003e 421540\u003cbr\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Volvo Penta\u003cbr\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Mechanical Belt Tensioner Assembly (OEM)\u003cbr\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Spring-loaded automatic belt tensioner\u003cbr\u003e\n\u003cstrong\u003eSystem:\u003c\/strong\u003e Engine Cooling \/ Accessory Belt Drive\u003cbr\u003e\n\u003cstrong\u003eQuantity Required:\u003c\/strong\u003e 1 per applicable engine\u003cbr\u003e\n\u003cstrong\u003eApproximate Weight:\u003c\/strong\u003e 700 g\u003cbr\u003e\n\u003cstrong\u003eDirect Cross-Reference \/ Replacement:\u003c\/strong\u003e 3092554\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch3\u003eWhat This Part Does\u003c\/h3\u003e\n\u003cp\u003eThe 421540 is a complete mechanical belt tensioner assembly used across a wide range of legacy Volvo Penta TAMD, TD, TWD, TAD, and TID diesel engines. Using a cable, compression spring, pulley, and shaft, it maintains correct belt tension as the belt stretches and wears in service — preventing belt slip, reducing pulley wear, and protecting belt-driven accessories including the alternator and cooling-system components. This is the complete assembly; the pulley, bearing, spring, cable, and body are also listed individually in Volvo Penta diagrams for sub-component replacement.\u003c\/p\u003e\n\n\u003ch3\u003eCompatible Applications\u003c\/h3\u003e\n\u003cp\u003eConfirm the exact engine designation and serial number before ordering. Volvo Penta used several visually similar tensioner assemblies across related engine families — do not select by appearance or pulley dimensions alone.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eVolvo Penta TAMD71B\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAMD74A\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAMD74C-A \/ TAMD74C-B\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAMD74L-A \/ TAMD74L-B\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAMD74P-A \/ TAMD74P-B\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAMD75P-A\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD61A \/ TD61AW \/ TD61ACE \/ TD61AG \/ TD61AP\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD610G \/ TD610M\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD630ME\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD71A \/ TD71AW \/ TD71ACE \/ TD71AG\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD710G\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TD730ME \/ TD730VE\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TID71A\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TWD610G\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TWD630ME\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TWD710G \/ TWD710P \/ TWD710V\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TWD730ME \/ TWD731VE\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TWD740GE \/ TWD740VE\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAD730G \/ TAD730V\u003c\/li\u003e\n\u003cli\u003eVolvo Penta TAD740GE \/ TAD741GE\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSerial Number Notice\u003c\/h3\u003e\n\u003cp\u003e421540 spans several generations of Volvo Penta marine and industrial diesels. Always confirm the complete engine designation and serial number against the applicable Volvo Penta parts diagram before ordering. Visual similarity alone is not a reliable fitment check for this tensioner family.\u003c\/p\u003e\n\n\u003ch3\u003eTensioner Sub-Components\u003c\/h3\u003e\n\u003cp\u003eVolvo Penta parts diagrams list the following as individually available components within the 421540 tensioner assembly:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e477312 — Cable\u003c\/li\u003e\n\u003cli\u003e471318 — Compression spring\u003c\/li\u003e\n\u003cli\u003e471323 — Spring guide\u003c\/li\u003e\n\u003cli\u003e471325 — Spring anchorage\u003c\/li\u003e\n\u003cli\u003e421541 — Nut\u003c\/li\u003e\n\u003cli\u003e1661878 — Pulley\u003c\/li\u003e\n\u003cli\u003e1544092 — Ball bearing\u003c\/li\u003e\n\u003cli\u003e471430 — Tensioner body\u003c\/li\u003e\n\u003cli\u003e471317 — Shaft\u003c\/li\u003e\n\u003cli\u003e471321 — Sealing ring\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhen to Replace\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBelt tension becomes weak or inconsistent\u003c\/li\u003e\n\u003cli\u003ePulley bearing is noisy, rough, or intermittent\u003c\/li\u003e\n\u003cli\u003eTensioner binds or does not move smoothly through its travel\u003c\/li\u003e\n\u003cli\u003ePulley runs out of alignment with the belt drive\u003c\/li\u003e\n\u003cli\u003eSpring or cable mechanism is damaged\u003c\/li\u003e\n\u003cli\u003eBelt repeatedly slips despite being in serviceable condition\u003c\/li\u003e\n\u003cli\u003eExcessive pulley or pivot play detected on inspection\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eInstallation Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eInspect the belt and all accessory pulleys before installing the replacement tensioner\u003c\/li\u003e\n\u003cli\u003eCheck for pulley misalignment, bearing roughness, and belt condition — replace the belt if worn or glazed\u003c\/li\u003e\n\u003cli\u003eUse the applicable Volvo Penta workshop procedure when releasing and reloading spring tension; do not force the tensioner beyond its designed travel range\u003c\/li\u003e\n\u003cli\u003eVerify correct pulley alignment and belt tracking after installation before returning the engine to service\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003ePart Number Cross-Reference\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Part Number:\u003c\/strong\u003e 421540\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStrongest direct replacement:\u003c\/strong\u003e 3092554 (421540 → 3092554)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCross-reference family (confirm by serial):\u003c\/strong\u003e 3095413, 3979897, 3183643\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical FAQ\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Is 3092554 a direct replacement for 421540?\u003c\/strong\u003e\u003cbr\u003eA: Yes. Parts catalog evidence identifies 3092554 as the primary replacement for 421540 within this tensioner family. If your engine parts list or dealer quotes 3092554, it is the correct modern equivalent. Additional numbers (3095413, 3979897, 3183643) are associated members of the same family but should be confirmed by engine serial before ordering.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Can I replace just the pulley or bearing?\u003c\/strong\u003e\u003cbr\u003eA: Yes. Volvo Penta diagrams list the pulley (1661878) and ball bearing (1544092) as separately available components. If only the bearing or pulley has failed and the tensioner body and spring mechanism are serviceable, ordering the sub-component is a practical option. Inspect the complete assembly to determine the appropriate scope of replacement.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: How do I confirm this tensioner fits my engine?\u003c\/strong\u003e\u003cbr\u003eA: Match the original tensioner part number and confirm against the Volvo Penta belt drive \/ accessory drive diagram for your specific engine model designation and serial number. Do not rely on pulley appearance or engine displacement alone.\u003c\/p\u003e\n\n\u003ch3\u003eParts Desk Insights\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eBest use case:\u003c\/strong\u003e Order 421540 (or confirmed replacement 3092554) when the belt tensioner on a TAMD, TD, TWD, or TAD diesel has shown bearing wear, spring loss, or binding during inspection — or as part of a major scheduled service on a high-hour engine. Replacing the drive belt at the same time is recommended to get full service life from the new tensioner.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCommon issues:\u003c\/strong\u003e The most frequent mistake is selecting this tensioner by pulley size or visual match without checking the original part number and engine designation — Volvo Penta used several similar-looking tensioner assemblies across TD, TWD, TAD, and TAMD generations that are not interchangeable. Also confirm the current service number with your dealer before finalizing the order, as the supersession chain for this part family can vary by engine serial range.\u003c\/p\u003e","brand":"VOL","offers":[{"title":"Default Title","offer_id":43564038979620,"sku":"421540","price":793.0,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/b2dd90c8-ff05-43d1-81dc-93a7c41af9ab.png?v=1788670031","url":"https:\/\/marisolmarine.com\/products\/volvo-932","provider":"Marisol Marine Company","version":"1.0","type":"link"}