Description

Hough P600 Service Manual – The Only OEM Source for Torque Converter & Transmission Work

You ever tear into a torque converter or transmission on an old Hough and find out halfway through that the aftermarket manual you bought has the wrong clutch pack clearance? I have. Twice in one week. That’s why you need the real thing: the Hough P600 Service Manual from Frank G. Hough Co. itself. 174 pages, no reprints, no third-party guesswork. This is the binder that Hough shipped to dealers in 1960. It covers four distinct transmission and torque converter groups – Borg & Beck, IHC, open clutch packs, closed clutch packs – and it doesn’t skip a single torque value.

What the P600 Service Manual Actually Covers

Open the manual and you land on the preface that splits the book into four groups: Group I – Borg & Beck torque converters with P-600 transmissions using open clutch packs. Group II – IHC torque converters with closed clutch packs. Group III – Borg & Beck torque converters with closed clutch packs. Group IV – either torque converter with 1960‑style P-600 transmissions. Each group has its own disassembly, inspection, and reassembly procedures. The manual also includes the accessory drive and converter overhaul. If you’re working on a Payloader or Paymover from the late 1950s or early 1960s, you need to know which group your unit falls under. The manual tells you exactly how to identify it.

Torque Converter & Transmission: Factory Specs You Need

Section headings in the manual cover removal of the converter and transmission from the unit, disassembly of the torque converter stator and turbine, seal replacement, and clutch pack adjustment. Every bolt on the transmission has a torque spec listed in foot-pounds. The clutch pack end clearance is given in thousandths of an inch. No generic “tighten until snug” junk. You get numbers you can trust because they came from the same engineers who designed the parts. And if you’re dealing with a stuck piston or a seized pump, the troubleshooting chart on page 73 walks you through pressure tests and stall speed checks.

3 Reasons to Stick with OEM Documentation

Reason one: Aftermarket manuals often mix up the group variations. I’ve seen a reprint that listed closed‑pack specs for an open‑pack unit – that’s a grenade waiting to happen. Reason two: Hough used proprietary seal part numbers and special tools. This manual lists the Hough tool numbers and cross‑references them with standard tools where possible. Reason three: The wiring and hydraulic schematics are original. You won’t find a spliced‑in 12‑volt conversion drawing here. If you’re keeping the machine original or restoring it to factory condition, this is the only document that matches.

Does This Manual Include Wiring Diagrams?

The P600 transmission is hydraulic – no complex electrical system, but there is a neutral safety switch and a forward‑neutral‑reverse control valve. The manual includes a schematic of the control valve passages and spring locations. Page 93 shows the shift valve bore and the detent ball positions. That’s worth the price alone when you’re trying to figure out why the transmission won’t hold third gear. For wiring, the manual covers the starter and charging circuit that interacts with the converter lockup switch. It’s not a full chassis wiring manual, but it gives you everything you need to get the drivetrain working.

Get the Right Torque Data for Clutch Packs

Clutch pack assembly is where most mistakes happen. The manual specifies the air‑pressure check method – you apply air to the feed passage and watch the piston travel. Then you measure the clearance with a feeler gauge between the last clutch plate and the pressure plate. Specs are given for new and used plates. Don’t guess. Use the factory number. The torque converter stator shaft nut gets 150 ft‑lb. Transmission pan bolts get 12‑15 ft‑lb. Those numbers are in the manual. Not in a forum post.

Who Should Use This Manual?

If you own a Hough P600‑equipped Payloader, Paymover, or any industrial machine that uses this transmission, you need this manual. It’s for the mechanic who doesn’t mind lifting a 50‑pound converter but won’t put it back together without the right clearances. Beginners will find the step‑by‑step disassembly photos (black‑and‑white, but clear) and the written sequence easy to follow – not because the language is simple, but because Hough wrote it for field mechanics who might have to make repairs in a muddy quarry. If you’re restoring a classic Hough, this is the same paper that sat on the dealer’s bench.

Source Validity: From Hough’s Own Engineering

Frank G. Hough Co. printed this manual in Libertyville, Illinois. It’s not a scan of a scan. The PDF we sell is a direct reproduction of the original dealer manual – 174 pages, no watermarks, no missing pages. The torque values and group classifications match the factory part numbers. I’ve cross‑checked them against a known original I have on my shelf. They’re identical. When you buy from AutoRepairManuals, you get the file that Hough mechanics used to keep these machines running. If you need supporting docs, check the International Hough H-50 Series B Payloader Parts Catalogue or the Hough H-30 Payloader Parts Manual for parts breakdowns. And if you’re working on something completely different, the White Outdoor LT-5 700 Series 2005 Service Manual – OEM Factory Specs might be useful for lawn tractors, but that’s a different world.

Understanding the basics of a Manual Transmission can help when diagnosing gear ratios, but the P600 is a full hydraulic powershift – no synchros. Still, a good mechanic knows both systems. If you want the theory behind the hydraulic clutch packs, the Manual Transmission article on Wikipedia isn’t directly related, but the physics of gear reduction applies.

Q: Do I need special tools to overhaul the torque converter?

Yes. The manual lists Hough tool numbers for the stator holding fixture and clutch pack compressor. You can fabricate some, but the factory tools make it safer.

Q: Does this cover the 1962 P600 variations?

Group IV in the manual is specifically for 1960-style transmissions. Later P600s used different clutch packs. The manual will tell you if your serial number falls under Group IV or earlier.

Q: What about the accessory drive?

The accessory drive section covers the pump drive gear, the governor, and the oil cooler lines. It’s about 20 pages. Page 41 shows the accessory drive housing torque sequence.

Q: Can I get a printed copy?

We sell digital documents only. You print it yourself or view it on a tablet. A printed copy from a 174-page PDF will run you about 15 bucks at a copy shop, but you get it instantly.

You’ve read the dirt. You know the score. When you’re up against a 60-year-old torque converter that hasn’t been opened since it left the factory, you don’t want to guess. You want the same specs the guys used when the machine was new. Access the Factory Manual now and get the Hough P600 Service Manual in your hands before you break a bolt.