Description

Hyster H135FT, H170FT, H175FT36, H155FT, H190FT Service Manual

If you are pulling a cylinder head on a Hyster H135FT or H190FT, you don’t guess on the valve sink depth. You look it up. That is what this 98-page factory service manual is built for. It covers the Kubota 3.8L diesel (Tier 4 Final) in the H135FT, H155FT, H170FT, H175FT36, and H190FT models. I have seen guys skip the Precautions Before Beginning Repair on page 2 and end up with a scored liner because they didn’t check oil pump clearances. This is the document Hyster sends to dealers – not a third-party rewrite. If you want to keep the engine running past 10,000 hours, you use the factory specs.

Precautions Before Beginning Repair – What That Safety Section Means

Page 2 is not filler. It tells you to disconnect the battery ground cable, block the truck, and use Hyster approved parts. The WARNING and CAUTION labels are orange and yellow for a reason. When you are working on the Exhaust System, SCR, and DPF, you need to know that diesel fuel and battery gas are flammable. The manual spells out lifting procedures – do not lift heavy parts by hand. That section alone has saved me from dropping a cylinder head onto my foot. Respect it.

Cylinder Head Assembly Repair – Valve Sink and Seat Inspection

This chapter walks you through removing the valve covers and fuel injectors, then the rocker arm assembly, then the cylinder head. The manual tells you to clean and inspect every part: valve guides, valves, valve sink, valve seat, valve springs. It gives the limits for valve sink depth and seat width. The install procedure includes the correct torque sequence for the cylinder head bolts. If you skip the Valve Clearance Adjustments section, expect a noisy valvetrain and lost power. I have used this procedure on a H155FT that came in with low compression – followed the manual, ended up with 0.010-inch clearance on intake and 0.012 on exhaust, and it fired right up.

Angular Deviation Procedure – Kubota 3.8L Diesel Engine

Under Drive Train, Camshaft, and Cylinder Block Repair, there is a specific procedure for angular deviation. If you are reassembling the bottom end after a rebuild, you need to check the connecting rod alignment. The manual shows how to measure it and what the spec is. Do not assume – the Kubota 3.8L has tight tolerances. I have seen a bent rod wipe out a cylinder wall because somebody swapped parts without checking this step. The honing and boring section tells you the oversize correction limits if you need to bore the block. That information is only in the factory manual.

Oil Pump Clearances – Inner Rotor to Outer Rotor

The lubrication system repair chapter covers the oil pump in detail. You remove the oil pan, suction tube, then the pump. The manual lists four clearances: inner rotor and outer rotor clearance, outer rotor and pump body clearance, rotor and cover clearance, and rotor shaft clearance. Each has a spec in inches. If any clearance is out, you replace the pump. The engine oil pressure spec is also here. Page 1 shows the engine identification label location so you know which engine variant you have. Do not skip the oil filter change procedures – standard and remote filter are both covered. Low oil pressure will kill a diesel fast. This section keeps you out of trouble.

Fuel System Repair – Injection Pump and Injector Testing

Fuel injectors get a full procedure: remove, inspect, clean, replace, install, and test. The injection pump removal and installation is also covered. If you are chasing a hard-start or low-power issue on a H175FT36, you can pull the injectors and bench-test them using the specs in this manual. The fuel system chapter includes the test procedure. I have fixed a H170FT that was smoking white by following the injector install torque – a previous tech had under-torqued them and they were leaking combustion gas into the return line. Factory spec, no guesswork.

Engine Specifications – Torque Values and Clearances

The last chapters are the meat: Engine Specifications, Standard Torque Specifications, Special Torque Specifications, and Special Tools. You get engine data, tuning specs, cylinder head data, intake/exhaust valve and guide dimensions, valve spring free length and load, rocker arm and shaft clearance, push rod length, gear train backlash, piston ring gap, crank journal clearance, and more. The torque chart covers standard bolt grades and special fasteners like the flywheel bolts and main bearing cap bolts. If you are assembling a long block, this is the page you will dog-ear. The special tools list tells you what pullers and adapters you need for the Kubota 3.8L – saves you from buying a tool you do not need.

Other engine service manuals for the Hyster line include the Hyster 4.3L V-6 Engine Service Manual and the Hyster H8.0FT H9.0FT 5.7L Engine Service Manual. For LPG models, see the Hyster LPG Fuel System 5.7L Engine Service Manual. If you need information on a Manual Transmission unit, that is a separate document. The Manual Transmission service manual covers gearboxes; this one is pure engine and drivetrain.

Who This Manual Fits

Home garage enthusiasts who rebuild their own forklifts will get the most out of this. If you are a shop owner with a H135FT in the fleet, this keeps your techs from wasting time on aftermarket diagrams that show the wrong oil pump clearance. Beginners should not touch a cylinder head without this manual – the valve clearance adjustment alone can ruin a head if you get it wrong. Professionals will appreciate that the torque specs are in ft-lbs with inch-lbs where needed, all from Hyster’s engineering department. No reprints, no third-party compression.

Source Validity – Factory OEM vs Aftermarket

This is a direct scan of the Hyster Part No. 4139176, SRM 1962, dated 2017. The cover says “Service Manual” and the safety page is signed by Hyster Company. Aftermarket manuals often omit the angular deviation procedure or use a generic torque chart. I have compared them head-to-head – the aftermarket missed the idler gear 3 backlash spec. That kind of mistake costs you a gear set. Stick with the original.

Does this manual include wiring diagrams?

No. It covers the engine and its systems only – no electrical schematics for the truck chassis.

What torque specs are provided?

The manual includes a Standard Torque Specifications chart and a Special Torque Specifications section. It covers cylinder head bolts, flywheel bolts, main bearing cap bolts, connecting rod bolts, and camshaft gear bolts. The exact values depend on the fastener grade and size, all listed in the Standard Torque Chart near the end. You will also find specific torque values for the Kubota 3.8L diesel, such as connecting rod bolts and camshaft gear bolts. Always use the factory spec – aftermarket manuals often get this wrong or omit the special torque values for the injector hold-downs and rocker arm pedestals. The manual has torque sequences for the cylinder head and the flywheel to prevent warping. If you are rebuilding the engine, you need these numbers.

You have a choice: chase parts diagrams and forum guesses, or access the factory manual that Hyster dealers use. This is the document that tells you exactly what clearances and torques to run. Access the Factory Manual and keep it on your bench tablet. Your engine will thank you.