Description

Hyster H4.0FT5, H4.5FTS5, H4.0FT6, H4.5FT6, H5.0-5.5FT Service Manual – 106 Pages

If you’ve ever cracked open a manual that tells you to “tighten until snug” on a cylinder head bolt, you know the kind of damage that causes. I’ve got twenty-eight years of ASE certification and a six-bay shop in San Antonio that sees Hyster forklifts every single week. This is a Hyster H4.0FT5, H4.5FTS5, H4.0FT6, H4.5FT6, H5.0-5.5FT Service Manual—the OEM book with part number 4057092. No third-party guesses. 106 pages of factory drop-dead data. Every torque spec, every clearance, every step for pulling the Kubota 3.8L diesel engine out of these trucks. If you skip the safety precautions on page 2, you’re asking for a fuel fire or a dropped assembly. I’ve seen both. This manual tells you exactly what not to do.

Engine Overhaul Coverage

You need to pull the cylinder head? The manual walks through valve covers, fuel injectors, rocker arm assembly, and valve clearance adjustments. Step by step: remove, clean and inspect, install. The cylinder head section alone covers valve spring removal, valve guide removal and install, valve seat inspection. Then there’s the timing gear case – crankshaft gear, idler gear, camshaft gear. Every gear has a backlash spec. You don’t get that from a third-party PDF. Then the drive train and camshaft section: how to disassemble pistons, connecting rods, crankshaft, camshaft. It even covers the angular deviation procedure for the Kubota 3.8L diesel. That’s page 26 information you will not find in a Haynes-style booklet.

Does This Manual Cover the Fuel System?

Yes, and it covers the DPF (Diesel Particulate Filter) as well. The fuel system repair chapter walks through removing and installing fuel injectors, cleaning and testing them, and the fuel injection pump. You get the Kubota 3.8L diesel fuel system specs – not generic stuff, but the exact part numbers and pressures from Hyster. The manual also includes the exhaust system and DPF section. If you’ve got an H4.0FT6 that’s running rough after a regen, you need these procedures. I’ve also sold a related manual for LPG models: Hyster LPG Fuel System 4.3L Engine Service Manual if you swing that way. But for diesel, this is it.

Valve Clearance Adjustments: Factory Procedure

Adjusting valves on the Kubota 3.8L diesel without the factory clearance numbers is a good way to burn a valve. The manual gives you the exact intake and exhaust valve clearances, the rocker arm shaft specs, and the push rod tolerances. There’s a special torque chart for the cylinder head bolts – not a generic chart from the internet. The standard torque specs table and the special torque table are both in the back. You get the outer rotor outside clearance, inner rotor to cover clearance, all of it. This is the kind of data that separates a rebuild that lasts from a re-rebuild next month.

106 Pages of Factory Spec Data

106 pages isn’t massive, but it’s dense. Every page counts. The engine specifications section at the back runs from engine data to tuning, cylinder head specs, intake/exhaust valve and guide dimensions, valve spring free length and load, camshaft lobe lift, idler gear shaft bushing clearance, and backlash for each gear. Crankshaft main journal and pin diameters, piston ring end gap, connecting rod bushing ID – all in imperial units. The special tools list is there too. You won’t be making a tool run in the middle of a job if you read it first. If you need an older Hyster transmission manual, check Hyster Service Manual 8000 SRM 1409 for the drive train side. Or the newer HYSTER Forklift Service Manual 0600 SRM 1961 for later model electronics.

Source Authenticity: OEM vs Aftermarket

I’ve seen aftermarket manuals that copy the torque specs from a Toyota Corolla and paste them into a forklift book. That’s not a joke. This manual is OEM from Hyster. Page 1 shows the SRM 1590 designation and part number 4057092. The safety warnings on page 2 are the same ones Hyster prints and updates. The copyright is 2017 Hyster Company. If you’re rebuilding a cylinder head or replacing a crankshaft, you need these numbers. Aftermarket manuals don’t give you the angular deviation procedure for the Kubota 3.8L diesel. They don’t show you how to check outer rotor clearance on the oil pump. This one does. For those of you wrenching on manual transmissions as well, I keep a Manual Transmission reference nearby when I’m doing clutch work, but that’s a separate operation.

Who Needs This Manual on the Workbench

If you’re a shop owner paying a tech to guess at a valve sink specification, you’re losing money. If you’re a home-garage enthusiast who bought a used H4.5FTS5 and want to do a full engine overhaul, this is your blueprint. The manual assumes you have basic mechanical sense – it doesn’t hold your hand – but it gives you every number you need. The oil pump rotor clearances, the piston ring end gaps, the connecting rod side clearance – all there. The serpentine belt removal and adjustment procedure for the cooling system. The water pump and thermostat removal and install. Even the flywheel and flywheel housing removal. Everything is broken down into remove, clean/inspect, install. That structure isn’t fancy, but it works. And that’s exactly how a pro should approach it.

Frequently Asked Questions

Does this manual cover all Hyster models from H4.0FT5 to H5.5FT?

Yes. The cover lists H4.0FT5, H4.5FTS5, H4.0FT6, H4.5FT6, H5.0-5.5FT (also called H80-120FT). It includes the Kubota 3.8L diesel engine with DPF. The manual does not cover LPG or electric models. For those, check the related manuals above.

What kind of torque specifications are included?

Plenty. Standard torque chart, special torque chart, cylinder head bolt specs, main bearing cap bolts, connecting rod bolts, flywheel bolts, oil pump rotor clearance tolerances. All in imperial units (lb-ft, in-lb, inch measurements).

Is there a wiring diagram in this manual?

No. This is a service manual for the engine, drivetrain, and mechanical systems. Electrical equipment coverage is limited to alternator and starter removal/install. Full wiring diagrams are in the corresponding electrical manual (SRM 1409 or SRM 1961).

Can a beginner use this manual to rebuild the engine?

If you know how to read a micrometer and understand basic engine assembly, yes. The manual won’t teach you how to use a torque wrench, but it gives you every step and spec. Beginners should read the safety precautions and the crankcase description before starting. I’d also recommend a Manual Transmission supplement if your truck has a manual gearbox.

Every time I see a shop using a printed-from-the-web copy of a generic manual, I cringe. You’re betting the engine on someone else’s typo. The Hyster factory book is the only source I trust for these trucks. 106 pages, OEM part number 4057092, SRM 1590. You can order it as a printed or digital copy. Either way, you get the real numbers.

Access the Factory Manual from AutoRepairManuals and put it on your workbench where you can actually read it. Don’t guess. Torque it right.