Yanmar 4JH3-DTE – Inboard Marine Diesel Engine 125 HP

With 125 hp at 3,800 rpm, the Yanmar 4JH3-DTE uses a turbocharged and intercooled 1.995L inline four-cylinder diesel configuration with direct injection. The stated 18.1:1 compression ratio and ISO 8217 DMA diesel requirement define its fuel-system specification. Hydraulic or mechanical transmission options, KMH4A or KM4A drive compatibility, and an SAE 4 flywheel housing establish the documented propulsion interfaces.

The 511-pound dry engine uses a 12V 60 or 80-amp alternator, heat-exchanger cooling with 7.0L coolant capacity, and forced lubrication with 5.0L oil capacity. A wet mixing elbow forms part of the specified exhaust arrangement. Listed BSO I and RCD I ratings, plus mechanical or hydraulic steering compatibility, provide further system-planning context.

Why Choose the Yanmar 4JH3-DTE Marine Diesel Engine

The 4JH3-DTE marine diesel engine combines 125 hp output with turbocharging, intercooling, and direct injection in a 1.995L four-cylinder platform. Buyers comparing higher-output mechanical propulsion packages can assess its hydraulic or mechanical transmission options, KMH4A or KM4A drive compatibility, and 12V alternator choices. Its 511-pound dry weight and SAE 4 flywheel housing add specific integration data before installation planning.

Warranty and Support

Warranty coverage for this legacy engine should be confirmed against the current Yanmar policy applicable to its purchase date, installation status, and operating market. provides product-information support before purchase and assistance with order-related questions. Review current warranty eligibility and coverage details on before placing your order.

Before Ordering the Yanmar 4JH3-DTE Marine Diesel Engine

Before ordering, verify engine-bed dimensions, mount locations, SAE 4 flywheel-housing compatibility, transmission selection, and KMH4A or KM4A drive requirements. Confirm your vessel supports ISO 8217 DMA diesel, turbocharger clearance, cooling-water intake, wet-exhaust routing, mechanical or hydraulic controls, charging wiring, ventilation, shaft alignment, and professional propulsion installation.