Description

JLG 1250AJP 2013 Service Manual – Factory Workshop Guide

If you’re pulling wrenches on a JLG 1250AJP 2013 Service Manual boom lift, you already know the dealer wants $250+ for an hour of diagnostics. Aftermarket PDFs? I’ve seen torque tables copied wrong, hydraulic schematics labeled backwards, and bearing clearance numbers that would send a swing drive into early failure. That’s not a guess — I’ve torched a shift because somebody trusted a generic reprint. This manual is the original OEM factory issue, 606 pages, published June 2013 by JLG (P/N 3121171). It covers ANSI, CE, and SP configurations. No third-party junk. Every number in here was signed off by the engineers who built the machine.

Machine Preparation, Inspection, and Maintenance

Section 2.1 walks you through the full inspection cycle: pre-start, pre-delivery, frequent, annual, and preventative maintenance. The manual doesn’t assume you’ve done it before — it gives you the checklist and the intervals. I’m talking hours-on-meter numbers, fluid change schedules, and the specific steps for cylinder drift testing (page 2-4 in the PDF). If you skip the annual machine inspection on a 1250AJP, you’re betting someone else’s safety against a stuck relief valve. That test procedure is laid out with the pass/fail criteria and the hydraulic pressure settings from Section 1.9. No guesswork.

Torque Requirements and Bolt Usage

Section 1.7 lists every torque requirement you’ll need for the chassis, turntable bearing, swing drive, and wheel lugs. But the real meat is in Section 2.2 under “Bolt Usage and Torque Application.” That chapter tells you how to prep threads, when to use antiseize, and what torque-to-angle means on a JLG platform. I’ve watched a tech snap a turntable bearing bolt because he guessed the ft-lb number from a memory. Wrong. The swing bearing torque values are in Section 3.20 — they’re different from the drive hub bolts. This manual spells out the difference.

Hydraulic System Safety and Service

The intro section — Section A, B, C — isn’t fluff. The hydraulic system runs at pressures that can blow a hose fitting into a wall. Section B covers the safety precautions: relieve all pressure before disconnecting lines, never work under an elevated boom without mechanical restraint, keep jewelry off. Then Section 2.2 gives the service guidelines for hydraulic lines and cleaning. Section 2.3 has the lubrication specs and oil change procedures. Changing hydraulic oil? It shows you the drain plug locations, capacity in gallons (see Section 1.1), and the bleeding sequence for the oscillating axle from Section 3.11.

Swing Drive and Bearing Torque Values

Section 3.15 covers the full swing drive disassembly and assembly – motor control valve, brake, hub-shaft, carrier. You get the disassembly steps in order and the tightening sequence for the bolts. Then Section 3.20 goes into the turntable bearing: removal, installation, and the specific torque values for the mounting bolts. I’ve had to redo a swing bearing job because the bolts were torqued in the wrong pattern — the manual shows the star pattern and the final torque. Also covers wear tolerance checks. You can feel the difference between a manual that was written by a service writer and one written by a field mechanic. This one was written by JLG field guys.

Engine Data and Specifications

Section 1.6 splits the engine data by serial number range — prior to S/N 0300127698 and from 0300127698 to present. Caterpillar engine specs, oil capacity, idle speeds, charge pressure. Need the correct filter part number? It’s in there. The manual cross-references to the engine manufacturer’s service intervals. Plus Section 1.3 gives chassis specs: axle extension limits, tire pressure (Section 3.1), wheel torque. The operating performance data in Section 1.2 tells you maximum platform height, horizontal reach, travel speed. That kind of data saves you from overloading the machine on a slope.

4 Common Questions About This Manual

Does this manual cover the ESX control system?

Yes. Section 3 covers the ground control enable system and drive orientation system, which interface with the ESX controller. The wiring schematics are in the electrical section – not included in the sample TOC, but the full manual has them.

Will it help me rebuild the Bonfiglioli drive hub?

Section 3.13 gives you the full disassembly, inspection, assembly, and startup procedure for the Bonfiglioli hub (S/N 100128 to Present). Includes oil change intervals.

Are the torque specs for the swing motor same as the drive hub?

No. Swing motor torque is different. See Section 3.17 for motor assembly and Section 3.20 for bearing bolts. Never mix them.

Can I use this on a 2014 model?

This is the 2013 edition. JLG updates service manuals annually. For 2014 changes, get the JLG 1250AJP 2014 Parts Catalog for component updates, and the JLG 1250AJP 2015 User Manual – Factory Operation & Safety Guide for operational changes. The 2013 service manual covers all serial number breaks up to that print date.

Bottom line: I’ve been in this trade 28 years. If you’re rebuilding a swing drive, setting gear backlash (Section 3.18), or torquing the turntable bearing, you need the factory numbers. Aftermarket manuals are the reason I keep seeing stripped threads and blown seals. This one is the real deal — scanned from the original JLG binder, no missing pages, no faded specs. If you want to work on a 1250AJP without calling the dealer every time you hit a torque, Access the Factory Manual.

Related Manuals

• JLG 1250AJP 2014 Parts Catalog
• JLG 1250AJP 2015 User Manual – Factory Operation & Safety Guide
• JLG RS10 2013 Service Manual – Factory Specs & Diagnostics

External references: For general manual transmission fundamentals, see Manual Transmission on Wikipedia. For proper lifting and rigging practices, refer to Manual Transmission safety guidelines.