An Inside Look At The Toyota Internal Combustion Forklift Engine

Every Toyota IC forklift engine has the same basic functionality. Toyota Certified Technicians are trained in this process so they can more easily understand the exact point of need when maintenance is required. Here’s an inside look about how an IC forklift engine works.

An ignition battery and gear-driven starter forces the engine to “crank over,” starting the internal combustion process. The carburetor mixes a combustible, liquid fuel with air and injects it into the cylinders through a valve. Within the cylinder, the piston is attached to a rod, which in turn is attached to the crankshaft.

Mechanical energy is produced when the spark plug introduces a spark to the compressed fuel/air mixture, igniting the explosion. The explosion drives the piston and rod down in the cylinder. Because of the way the crankshaft is designed, it will convert the downward energy of the piston and rod to the mechanical energy (RPMs).

A series of these cylinders are connected to the crankshaft in the block. The block contains other mechanisms, like the cam shaft, which uses the RPMs to open and close the valves in precise timing sequence. This mechanical energy also drives the alternator or generator (found mounted to the engine and driven by a belt) which supplies current to the forklift’s electrical components. Additionally, the electricity produced in this way is used to drive the power steering and lift/tilt hydraulic pumps.

Internal combustion engines come in three main types, each categorized by the type of fuel they burn. Deciding between them depends on your specific forklift application and operational strategy

• Forklift Liquefied Petroleum Gas (LPG) engines run on a gas that occurs naturally. LPG is commonly used for gas grills.
• Compressed Natural Gas (CNG) engines use the same fuel supplied to homes and businesses to power stoves, furnaces and other appliances.
• Diesel engines use diesel fuel, a lower grade fuel not as refined as gasoline and therefore, not as combustible.

Each type of fuel provides different advantages that will then impact the operation of the forklift. Consider the below list that shows which forklifts can come equipped with forklift diesel engines and CNG engines and ask your locally authorized Toyota dealer about what choosing one can mean for your operation.

CNG Options:

• Core IC Cushion (up to 6,500 lb. capacity)
• Core IC Pneumatic (up to 6,500 lb. capacity)

Diesel Engine Options

• Mid IC Pneumatic (8,000-11,000 lb. capacity)
• Large IC Pneumatic (13,500-17,500 lb. capacity)

Diesel Engine Only:

• High-Capacity IC Pneumatic (22,000-125,000 lb. capacity)
  • Shorter load centers are available in LP

But which engine comes in each of our forklifts? The below guide will help you understand the differences between each Toyota forklift engine. But one thing that’s consistent across every forklift engine we produce? Expert engineering.

Four forklift engines are distributed across our internal combustion line

4Y Forklift Engine
Core IC Cushion | Core IC Pneumatic

1ZS Forklift Engine
Core IC Diesel Pneumatic

1FS Forklift Engine
Large IC Cushion | Box Car Special | Paper Roll Special | Mid IC Pneumatic | Large IC Pneumatic

1KD Forklift Engine
Mid IC Diesel Pneumatic | Large IC Diesel Pneumatic

But what exactly is the difference between these forklift engines that come in each of these models? Here’s a breakdown of each to help you choose the best available option.

Toyota 4Y Engine

The Toyota 4Y Engine was introduced in 1986, and it has been one of the industry’s longest-lasting, most durable forklift engines ever since. The 4Y Engine is unique in that it is the cleanest engine in the industry, and its emission standards rival the emission standards of any competitive internal combustion engine.

• The Toyota 4Y Engine is extremely efficient, which makes it tolerant of extreme temperatures. From outdoor applications in Minnesota to paper mills in Georgia, this engine runs smoothly.
• Due to its compact design, this engine works well in Toyota’s Core Products, such as the Core IC Cushion and Core IC Pneumatic.
• It is common to find Toyota Forklifts operating with 4Y Engines that have run for more than 30,000 hours and haven’t had a major overhaul.

Here’s deeper dive into how the Toyota 4Y Engine functions: