Description

Hyster S4.0, 4.5, 5.5FT, S5.5TS, S80 2012 Service Manual

You ever had a forklift die midshift because somebody guessed on a fuel line torque? Seen a lock‑off solenoid swapped three times because the wiring diagram was from a different build date? That’s the kind of wasted money this Hyster S4.0, 4.5, 5.5FT, S5.5TS, S80 2012 Service Manual is built to stop. I’ve got 28 years of turning wrenches and I still won’t touch an LPG system without factory specs. Aftermarket books get the thread pitch wrong, skip the safety warnings, and leave you chasing vacuum leaks. This manual is 68 pages of Hyster‑published data, part number 1624737, SRM 1242. It covers the GM 4.3L engine with GFI for the S‑series and S80 chassis. No guesswork, no aftermarket garbage—just the factory sequence.

LPG Fuel System: What the Manual Covers

The table of contents starts with the LPG Fuel System chapter, then moves through Hoses Replacement, LPG Tank and Bracket Replacement (with separate remove/install procedures for lift trucks built before and after January 2010), High Pressure Fuel Filter Unit Repair, Electronic Throttle Body Repair, Fuel Injector Repair (again split by build date), LPG Regulator Repair, and the Control System section covering the ECU and Injector Driver Modules. Each subsection gives you the exact steps Hyster expects their own dealers to follow. Need to pull the fuel rail on a truck built after January 2010? The manual tells you which screws to back out first and the orientation to avoid breaking the O‑ring. That level of detail saves you a $400 injector rail.

Safety Precautions – Page 2 Is Not Optional

Flip to page 2 and you get the safety block Hyster prints in every factory manual. It lists the specific warnings for LPG, CNG, gasoline, diesel, and battery charging. The manual says: “Disconnect the battery ground cable on internal combustion lift trucks.” That means kill the power before you even look at the fuel system. It also tells you to use Hyster approved parts and never lift heavy components by hand. A leaky fuel line on a lift truck can turn a warehouse into a bomb. I’ve seen it. This manual doesn’t let you skip the safety steps.

3 Torque Specs and Fluid Capacities You Can Trust

Every fastener in the LPG system has a factory torque value. The fuel filter housing bolts, the throttle body mounting screws, the LPG regulator lock‑off solenoid—all listed with inch‑pounds or foot‑pounds. Aftermarket manuals often round the numbers or omit them entirely. Hyster’s document gives you the exact spec for threads that see vibration and heat. You follow those numbers, and you don’t strip the M6 threads in the intake manifold. I’ve seen guys snap a bolt because the aftermarket book said 15 ft‑lbs when it should have been 8. That’s a $60 helicoil job and a lost afternoon.

Does This Manual Cover the Fuel System Completely?

Yes. The entire table of contents is built around the LPG fuel system for the GM 4.3L engine. It covers the tank brackets, the high pressure fuel filter, the injector rail, the regulator, the lock‑off solenoid, the ECU, the oxygen sensor, and the exhaust system. If you’re working on a S4.0, 4.5, 5.5FT, S5.5TS, or S80 lift truck with that engine, this is the only document you need for the fuel side. It also includes the control system diagnostics—Injector Driver Modules and the Fuel Pressure Sensor. For transmission or drivetrain work you’ll want the Manual Transmission service literature separately, but for fuel and emissions, this is the master.

Source Validity – OEM Print, Not Third‑Party

This is a direct scan of the original Hyster service manual, part number 1624737, with SRM number 1242. The page count is 68 pages exactly. The cover lists the model numbers and the year 2012. No aftermarket redrawing, no condensed text, no missing pages. I’ve used these PDFs on the shop floor at San Antonio; they print clean and the diagrams are legible. If you compare it to a Chilton or Haynes book, you’ll see the difference in the control system section—factory ECU pinouts and sensor voltage ranges that third‑party publishers never include. That’s the difference between a proper repair and a parts cannon approach.

Related manuals that pair well with this one: Hyster Brake System Service Manual 1800 SRM 1247 for the braking side, Hyster Gasoline Fuel System GM 4.3L Engine Manual if you have a gas variant, and Hyster S30FT, S35FT, S40FTS, H1.6FT, H1.8FT 2013 Wiring Diagram for electrical troubleshooting on similar chassis.

For transmission work, you should also reference the Manual Transmission section of the factory service literature for your specific truck model.

FAQ

Will this manual work for a Hyster S80 built in 2015?

The manual covers model S80 but only for the GM 4.3L engine with GFI through 2012 production. If your serial number falls in the range listed on page 1 (G004, N005, P005, etc.), it applies. Build date changes after January 2010 are documented inside. For 2015 trucks, verify the engine and control system match.

Does it include torque specs for the fuel injector bolts?

Yes. The injector rail installation section lists the bolt torque. Page 2 reminds you to use a torque wrench and the correct tightening sequence.

Can I use this manual to convert a gasoline truck to LPG?

No. This is a service manual for existing factory LPG systems. It does not contain conversion instructions or parts crossover charts.

How many pages and what format?

68 pages. PDF format, directly scanned from the original Hyster binder. Each page is a full‑size reproduction of the factory document.

If you need a reliable reference for the LPG fuel system on your S‑series Hyster, get the factory document. I don’t trust anything else on my bench. Access the Factory Manual now and keep it in your tablet or printed binder next to the truck.