Description

Clark-hurth 25, 30, 36 Service Manual – 222 Pages of Factory Specs

If you’re wrenching on a Clark-hurth 25, 30, 36 Service Manual equipped lift truck and you don’t have this book in your bay, you’re guessing. Guessing on a forklift gets you a snapped caster bolt or a battery cable that arcs across the frame. I’ve been turning wrenches for 28 years, and the difference between a job that stays fixed and one that comes back on a hook is having the original factory procedure in front of you. This isn’t a reprint from some third-party outfit that scanned a library copy. This is the dealer-level publication – 222 pages of Clark’s own technical data, printed for CLARK dealers only.

You need the charge pressure for the hydraulic pump? You need the backlash spec for the drive unit? It’s in here. But you have to read the safety section first. Page 1 starts with an important safety notice. Clark didn’t put that there to fill space. They put it there because industrial trucks kill people when you skip steps. The manual includes a full pictorial index so you can find what you need without flipping through every page. I’ve used it to pull a drive motor out of a HWD-36 in less than three hours – because I knew which bolts to hit and which ones to leave alone until the unit was on the bench.

Lubrication & Planned Maintenance – PM Check Sheet

Section 01 covers lubrication specifications and the hydraulic system. There are separate lubrication charts for rider models and walkies. If you’re maintaining a fleet of PWD-30s and P-25s, you need to know which grease goes in the caster bearings and which oil in the drive unit. The manual spells it out. There’s also a section for optional equipment and miscellaneous linkage – things that usually get missed during a quick lube job. The PM check sheet in the front is a printable list I tape to the dash of every truck I service. Don’t rely on memory. Use the checklist.

Battery Handling and Maintenance – Safety First

Section 12 covers battery removal, cleaning, charging, and electrolyte levels. Forklift batteries are heavy and dangerous. The manual walks you through vent inspection and compartment cleaning. It also includes a section on keeping battery records – something most shops ignore until a warranty claim gets denied. I’ve seen too many guys drop a battery terminal wrench across the posts and weld it solid. Clark’s procedure tells you exactly how to disconnect and install the battery without creating a dead short. Follow it.

Electric Motors – Inspection and Testing Procedures

Sections 16 go deep into drive (traction) and pump motor maintenance. There is a full test for motor insulation resistance to ground. Brush and commutator inspection is covered with a chart that shows acceptable wear limits. If you’ve ever had to undercut a commutator on a Clark forklift, you know the specs matter. The manual includes frame and field assembly testing, open circuit and grounded circuit checks. It also covers equalizer winding connections and standard winding connections. That section alone has saved me hours of diagnostic time on a PWD-36 that was pulling only half power.

EV-T5 Control Troubleshooting – 11 Operational Sequences

Section 19 is the thickest part of the book. It covers the EV-T5 solid state control system – description, features, maintenance, and troubleshooting. There are 11 operational sequences printed out step by step. When the truck goes dead and the control card isn’t lighting, you run through the sequence. The manual includes flow chart troubleshooting for 9 symptoms. I’ve used symptom 3 (no power in forward) to isolate a bad I C capacitor in under ten minutes. The component identification and internal wiring diagrams are printed in the same chapter. Do not try to guess your way through an EV-T5 fault without this book. You’ll waste a day replacing parts that aren’t broken.

Hydraulic System Torque Specifications

Section 28 covers the hydraulic unit removal, installation, and torque specs. Section 34 covers lift cylinder removal, disassembly, inspection, and reassembly with installation specifications. If you overtighten the lift cylinder gland nut, you’ll bind the seals and get a drift. Clark lists the torque. Use it. Section 40 includes a full truck specifications table with battery, brake motor, control, electrical, hydraulic system specs, service weights, and torque values. Page 40 is the one I tab with a red flag. It’s the quick reference for almost every fastener on the truck.

Source Validity: OEM Dealer-Only Publication

This is not a reprint or a third-party knockoff. The OCR excerpt from the original clearly states “Copyrighted Material – Intended for CLARK dealers only – Do not sell or distribute.” That means the data inside was locked down by Clark Equipment Company. They didn’t want aftermarket shops copying their torque values and getting them wrong. When you buy this Service Manual from AutoRepairManuals, you’re getting the exact same book a dealer tech would have on his bench in 1991. The wiring diagrams match the actual harnesses. The test procedures were written by Clark engineers who designed the EV-T5 control. I’ve compared this to aftermarket manuals – they skip details like commutator undercutting depth and snubber capacitor values. This manual doesn’t skip.

For related factory documentation, check out the CLARK 12 25 Technical Manual for smaller platform specs, or the Clark-hurth 25, 30, 15, 18, 20 1998 Service Manual – OEM Factory Specs for later model coverage. If you’re working on heavy-duty transmissions, the Spicer Clark-hurth HR Service Manual – Factory Specs for Heavy-Duty Transmission covers those units. For general knowledge on manual transmission theory, Manual Transmission and Manual Transmission articles on Wikipedia provide background, but they won’t help you set backlash on a Clark drive unit. You need the factory book for that.

Who Needs This Manual?

If you own a Clark P-25, P-30, HWP-30, HWP-25, PWD-30, PWD-25, HWD-30, HWD-25, or HWD-36, this is your manual. If you run a shop that services industrial forklifts, buy a copy for each tech. The section on planned maintenance procedures alone will keep your customers’ trucks out of the breakdown bay. Beginners should start with the PM check sheet and the battery section before tackling the EV-T5 control. Professionals will go straight to the torque spec pages and the operational sequences. The book is 222 pages – thick enough to have everything, thin enough to keep on the workbench without covering your other tools.

Does this manual cover the Clark 36 model?

Yes. It covers 25, 30, and 36 series – both walkie and rider models.

Are the torque values in foot-pounds or inch-pounds?

The manual uses imperial units consistently. Torque specifications are given in foot-pounds for all major fasteners – caster bolts, hydraulic unit bolts, drive unit hardware. The section on electric motors includes some smaller fastener torque in inch-pounds when appropriate. Always check the specific spec table in section 40 or the relevant component section. Clark cross-references torque values in multiple locations, so if you’re assembling a lift cylinder, the spec appears in both section 34 and the master torque table on page 40. Do not assume one torque fits all – the manual lists different values for different bolt grades.

Can I use this manual to troubleshoot an EV-T5 control that won’t power up?

Yes. Section 19 contains seven pages of trouble flow charts covering nine symptoms. It also includes component identification for the snubber, current sensor shunt, thermal protector, and I C capacitors. The operational sequences walk you through every state of the control card. If you have a multimeter and this manual, you can isolate the fault.

Is this a digital PDF or a printed book?

AutoRepairManuals sells digital documents. You get the full OEM PDF – 222 pages, searchable text, printable. No watermarks, no missing pages. You can put it on a tablet in the shop or print the pages you need for a specific job.

Access the Factory Manual and get the original Clark data on your screen before you touch another bolt. You’ll work faster, safer, and you won’t have to redo a job because the torque was off. That’s what twenty-eight years of turning wrenches taught me: spec is king, and Clark’s spec is in this book.