Yanmar 4TNV & 4TNE Turbocharger Guide — IHI RHF4/RHF5 OEM Parts for Compact Excavators & Forklifts | HHX PARTS

Yanmar TNV and TNE: The Engines Inside the World’s Compact Equipment

When a Komatsu PC30 mini excavator digs a utility trench in a European city centre, or a Bobcat compact loader moves material in a North American warehouse, or a TCM forklift lifts pallets in a Japanese port — the engine turning the hydraulic pumps is almost certainly a Yanmar. The 4TNV und 4TNE four-cylinder engine families are the dominant compact diesel platform in the global mini and compact equipment market, and have been for decades.

Yanmar’s TNV series (the modern generation) and the earlier TNE series together power an extraordinary range of equipment from over 40 different OEM manufacturers worldwide. The turbocharger on these small but hard-working engines is a precision IHI unit — significantly smaller than the turbos found on full-size construction equipment, but operating under equally demanding duty cycles in confined spaces with limited cooling airflow.

At HHX-TEILE, we supply turbochargers for Yanmar-powered compact equipment across the TNV and TNE engine families, alongside related Isuzu and Hino compact engine applications. This guide gives workshop technicians, compact equipment dealers, and parts distributors the complete cross-reference data to specify, source, and install the correct replacement unit.

Yanmar Engine Family Overview: TNE vs TNV

Turbocharging in the TNV/TNE family: Not all Yanmar TNV and TNE engines are turbocharged. The “T” suffix in the model designation indicates a turbocharged variant (e.g., 4TNV98T, 4TNE98T). Naturally aspirated variants (without the T suffix) do not have a turbocharger and cannot simply be fitted with one without extensive engine modification. Always confirm the engine suffix before ordering a turbocharger.

OEM Turbocharger Platform: IHI RHF and RHB Series

Yanmar uses IHI (Stone) small-frame turbochargers across the TNV and TNE turbocharged variants. These are among the smallest production turbochargers in the diesel engine aftermarket — compact, lightweight, and precision-engineered for the low-mass-flow requirements of 1.6–3.3L four-cylinder engines. Key characteristics:

• Primary models: IHI RHF4, RHF5, RHB31, RHB32, RHB52 — progressively larger frames for larger engine displacements
• Bearing system: journal (sleeve) bearings, oil-lubricated — the small oil passages in these compact units are especially sensitive to oil contamination and coking
• Compressor wheel: very small diameter (as small as 35mm inducer on RHB31) — any debris ingestion causes immediate blade damage
• Turbocharger weight: 1.5–4 kg depending on model — much lighter than truck or excavator turbos; handle carefully to avoid housing damage
• OEM part number format: Yanmar uses a 9-digit format: 129xxx-18010 as the primary reference across most turbocharged TNV/TNE applications

OEM Cross-Reference by Engine Model

4TNV84T — Compact Engine (Tier 3 / Tier 4)

4TNV88T / 4TNE88T — Mid-Size Compact Engine

4TNV94L / 4TNE94 — Medium Compact Engine

4TNV98T / 4TNE98T — Standard Compact Engine (Most Common)

The 4TNV98T and 4TNE98T are the most widely deployed turbocharged Yanmar engines — found in the largest range of compact excavators, telehandlers, and industrial equipment worldwide. This is the highest-demand Yanmar turbocharger SKU.

4TNV98CT — Tier 4 Final Compact Engine

4TNV106T / 4TNV106TT — Larger Compact Engine

Hino W04DT / Yanmar 4TN100 — Industrial Compact

HHX PARTS In-Stock Products for Yanmar / Related Compact Engines

The following turbochargers for Yanmar-powered and related compact equipment are available from HHX PARTS:

Yanmar / Hino Compact Engine

• RHB52 Turbocharger 24100-1880A / VB130059 / 24100-1511A — For Hino W04DT / Yanmar 4TN100 diesel engine — compact forklifts and industrial applications

Isuzu Small Engine (Related Compact Applications — JCB / Yanmar-competing)

• RHB32B Turbocharger 8980305710 / 02/803060 — For Isuzu 4LE1 / 4LE2 / 4EC1T — JCB 8065RTS, 8055ZTS compact excavators (competing platform to Yanmar TNV)

For Yanmar 4TNV84T (129508-18010), 4TNV98T (129935-18010 / 129928-18011), 4TNV98CT (1704231274), and 4TNV94L (129795-18010) — contact our technical team directly with your Yanmar part number and engine serial. We source and supply to order with lead times significantly shorter than Yanmar dealer channels. All enquiries receive a response within 24 hours.

Common Applications: Machines That Use Yanmar TNV / TNE Engines

Komatsu Compact Excavators (Largest Single Application Group)

• PC30MR-3 / PC35MR-3 / PC40MR-3 — 4TNV84T engine (RHF4 129508-18010)
• PC55MR-3 / PC58UU — 4TNE88T / 4TNV88T engine (RHB52)
• PC70MR-3 / PC78MR-3 / PC78US — 4TNV94L engine (RHF4 129795-18010)
• PC88MR-8 / PC95R-2 — 4TNV98T engine (RHF5 129935-18010)
• Vio45-3 / Vio55-5A — 4TNV98 / 4TNV98T (RHF5 129928-18011)

John Deere Compact Excavators

• John Deere 85G — 4TNV98T engine (RHF5 129935-18010)
• John Deere 75G / 75GLC — 4TNV98T engine
• John Deere 35G / 50G — 4TNV84T / 4TNV88T engine

Takeuchi Compact Excavators

• Takeuchi TB285 / TB290 — 4TNV98T engine (RHF5)
• Takeuchi TB175 — 4TNV94L engine (RHF4)
• Takeuchi TB260 / TB270 — 4TNV98T engine

Bobcat and Gehl Compact Equipment

• Bobcat E50 / E55 / E60 compact excavators — 4TNV84T / 4TNV98T Yanmar engine
• Bobcat S750 / S770 skid steer loaders — 4TNV98T engine
• Gehl RS series telehandlers — 4TNV98T engine (RHF5 129935-18010)
• Mustang compact equipment — 4TNV84T Yanmar engine

Yanmar Brand Excavators

• Yanmar SV100-2PB — 4TNV98CT Tier 4 engine (RHF5 VGT 1704231274)
• Yanmar ViO55-6B / ViO80 — 4TNV98T engine
• Yanmar B50W / B75W wheel excavators — 4TNV98T engine

IHI and Sumitomo Compact Excavators (Japan Market)

• IHI 75NX / IHI 80NX — 4TNV94L engine (RHF4)
• Sumitomo SH80XU — 4TNV98T engine (RHF5 129928-18011)

Forklifts and Material Handling

• TCM / Sumitomo diesel forklifts — 4TNE94 engine (compact counterbalance 2–3.5 ton)
• Hino-powered compact forklifts — W04DT / 4TN100 engine (RHB52 24100-1880A)
• Various Asian market compact forklifts — 4TNE84 / 4TNE88 engine platforms

Telehandlers and Aerial Work Platforms

• JLG compact telehandlers — 4TNV98T Yanmar engine
• Manitou MT523 / MT625 compact telehandlers — 4TNV98T engine
• Haulotte compact boom lifts — Yanmar TNV engine variants

6 Warning Signs Your Yanmar Compact Engine Turbo Is Failing

1. Black smoke under hydraulic load — the most common early symptom on Yanmar-powered compact excavators. During heavy digging, loading, or swing cycles that demand full hydraulic power, a worn RHF4 or RHF5 turbocharger cannot maintain boost, causing visible black smoke as the engine over-fuels. Often dismissed as “normal for a compact machine” — it is not.
2. Loss of digging or lifting force — compact excavator operators notice turbo wear first as reduced breakout force or inability to maintain rated digging depth under continuous operation. The effect is subtle at first and gradually worsens over hundreds of hours. If the machine feels “softer” than it used to, turbo inspection is warranted.
3. Oil consumption increase on compact forklifts (4TNE94) — worn RHF4 seals on 4TNE94-powered compact forklifts manifest as measurable oil consumption between service intervals. The very small oil passages in the RHF4 mean seal wear progresses quickly once it begins — inspect the air filter housing for an oily film at every 250-hour service.
4. Turbo whine during acceleration on Komatsu PC88 / John Deere 85G — bearing wear on the RHF5 produces a high-pitched whine during engine acceleration from idle. The sound is easy to mistake for hydraulic pump noise in a confined cab — test by listening with the hydraulic control held in neutral and engine revved: a persistent whine not related to hydraulic demand indicates turbo bearing deterioration.
5. Shaft play detected during inspection — compact engine turbos have very fine journal bearing clearances compared to larger units. Axial play beyond 0.10 mm or radial play beyond 0.3 mm on an RHF4 or RHF5 indicates bearing wear past service limit. Check at every 500-hour major service on high-cycle compact equipment.
6. VGT fault codes on Tier 4 Final machines (4TNV98CT) — the Tier 4 Final 4TNV98CT uses a variable geometry RHF5 turbocharger with electronic actuator. VGT-related fault codes (boost deviation, actuator position error) frequently appear on high-hour Yanmar SV100-2PB and Komatsu Tier 4 compact machines. Always test the actuator independently before condemning the turbocharger assembly — actuator failure is more common than mechanical turbo failure on these engines.

Compact Engine Turbo: Why Failures Happen Faster Than on Large Equipment

Yanmar TNV / TNE turbochargers fail at higher rates relative to their service life specifications than turbos on full-size equipment. Understanding why helps distributors and technicians advise customers on preventive maintenance:

Small Oil Passage Size

The oil feed passages in IHI RHF4 and RHF5 turbochargers are significantly narrower than those in larger HX35W or RHG6 turbos — as small as 0.8–1.2 mm in some sections. Even minor oil contamination or partial coking causes proportionally greater flow restriction. Oil change intervals, oil quality, and cool-down procedures have an outsized effect on these small turbochargers.

High Duty Cycle in Confined Spaces

Compact excavators and forklifts often operate at full hydraulic load for extended periods in areas with poor air circulation (trenches, indoor warehouses, tunnels). The combination of high engine load and limited cooling airflow keeps the turbo running hotter than equivalent-size equipment in open environments.

Frequent Hot Shutdown on Forklifts

Forklift operators routinely shut down the engine immediately after completing a lift — often multiple times per hour. Each hot shutdown leaves the small RHF4 bearings at elevated temperature without oil circulation, accelerating the oil coking cycle. Installing a simple turbo timer on any Yanmar-powered forklift used in high-cycle indoor operations is one of the most cost-effective preventive maintenance investments available.

Air Filter Neglect in Dusty Site Work

Mini excavators working in demolition, quarry, or dry-season earthmoving environments face the same dust ingestion risk as large excavators — but the smaller compressor wheel is destroyed by far less material. A single air filter bypass that takes 500 hours to destroy an HX35W turbo on a PC200 can destroy an RHF5 on a PC88 within 50 hours.

Installation Checklist for Yanmar Compact Engine Turbos

1. Flush the oil system and replace the filter — mandatory before fitting a new RHF4 or RHF5. The small passages in these turbos are easily blocked by metallic debris from a failed unit. Use a clean funnel and fresh oil.
2. Inspect and replace the oil feed line — the banjo bolt orifice on Yanmar compact turbos is very fine. Any partial restriction will starve the new unit. Replace the complete feed line assembly, not just the banjo bolt.
3. Pre-lubricate through the oil inlet port — pour approximately 20–30 ml of clean engine oil into the inlet port (less than larger turbos due to smaller housing volume) and rotate the shaft by hand before installation.
4. Disable fuel and crank for 10 seconds before first start — build oil pressure before enabling the fuel system. On Yanmar engines, disconnect the fuel stop solenoid electrical connector to prevent fuel delivery during cranking.
5. Idle for 5 minutes on first start — Yanmar TNV engines should idle at low RPM for at least 5 minutes before any hydraulic load is applied. Do not operate any hydraulic function until oil temperature has begun to rise.
6. Check for boost leaks in the charge air system — compact engines have short charge air paths with multiple silicone hose joints. Inspect all connections immediately after installation and again after the first 10 operating hours.
7. Confirm VGT actuator calibration on Tier 4 machines — after fitting a new turbocharger on 4TNV98CT engines, use Yanmar diagnostic software (YEDP) or Komatsu PC-HELPER to re-calibrate the VGT actuator position range before operating under load.

Why HHX PARTS for Yanmar Turbochargers?

• Complete TNV / TNE coverage — RHF4 and RHF5 across 4TNV84T, 4TNV88T, 4TNV94L, 4TNV98T, 4TNV98CT, and related Hino / Isuzu compact engine applications
• OEM 129xxx-18010 cross-reference — we maintain the full Yanmar IHI part number database including supersessions across TNE and TNV production generations
• New IHI-type units — fresh components to OEM tolerances, dynamically balanced before shipment; not remanufactured cores
• Shorter lead times than Yanmar dealer channels — OEM Yanmar turbochargers typically require 4–8 week lead times through official dealer networks; we ship stocked units within 7 days
• Technische Unterstützung — engine serial number cross-referencing, VGT vs fixed geometry confirmation, and Tier specification matching before dispatch
• Global supply — serving compact equipment dealers, rental fleet operators, and independent workshops across Asia, Europe, Australia, and Africa

Further Reading

• Isuzu 4HK1 & 6HK1 Turbocharger Guide — RHF55V for Hitachi ZX200
• Komatsu Excavator Turbocharger Guide — SAA6D107, SAA6D114 & More
• The Complete Turbocharger Maintenance Manual
• The Complete Turbocharger Buyer’s Guide: 8 Costly Mistakes to Avoid
• Turbocharger Complete Guide 2025

Request a Quote for Your Yanmar Turbocharger

Send us your Yanmar OEM part number (129xxx-18010 format), engine model suffix, or compact equipment make and model — and we will confirm the correct unit, availability, and pricing within 24 hours.

• Email: gzlh2022@gmail.com
• Phone / WhatsApp: +86 18170714612
• Website: www.hhxparts.com