5 Common Causes Why Your Forklift Engine Doesn't Start

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Do you have a forklift that won't start? If so, don't worry - you're not alone. A lot of people encounter this issue with their forklifts. In this post, we'll outline 5 causes for why your forklift might not be starting up. By understanding what's causing the problem, you can take steps to correct it and get your forklift back up and running. So, without further ado, let's get started!

Table of contents

  1. Why a Forklift Engine does not start
  2. Forklift Battery
  3. Ignition system components
  4. Lift Parts Warehouse: A trustworthy Forklift Parts supplier
  5. Takeaways

Why a Forklift Engine does not start

There are many reasons why a forklift doesn't start. So for you to have an idea of what could be causing that problem, we have listed out 5 of them, so you know where to begin looking:

Forklift Battery

All forklifts have batteries that are supposed to start the engine. However, just like every other machine out there with moving parts, your battery needs to be maintained and taken care of if you want it to work optimally for as long as possible. know more about wheel battery powered electric forklift, here.

Why is your battery without charge?

Check the battery charger: Your battery charger may have stopped working. The best thing for you to do in this case would be to replace it or get it repaired by a professional. However, check to ensure that it is not your battery charger by testing it on another forklift truck or lead-acid battery.

Check water level (in the case of lead-acid batteries): The optimal water level in lead-acid batteries depends on the type of battery and the manufacturer's specifications. Generally speaking, you need to check your batteries at least once a month by opening up cells. In case a low level is found, refill the battery.

Check connections: This is probably the simplest issue to fix. It doesn't take an expert mechanic to figure this one out, especially if you have a lead-acid battery. Check whether your battery is plugged in or not. The cables may be corroded as well. Also, make sure they are fully connected to both the battery and the starter of your forklift. It is needed to replace all the worn wires for the electricity fluids without problems.

How old is your battery?

One of the prime reasons for a forklift not starting is its battery. The battery may have already reached its life expectancy or may be experiencing complications.

battery measurements
Forklift Battery Checking

Ignition system components

The engine components of an internal combustion forklift work together to turn fuel into energy that can power a forklift.

  • Spark plugs are subjected to severe environments that include high temperature, vibration, and combustion, among other things. As such, it is essential that you understand what could happen if the spark plugs in your forklift malfunction due to many possible reasons. You need to replace spark plugs that are experiencing any kind of problems and not just because they are old. The main reason is that it will affect the performance of your forklift by affecting its engine power. The forklift will be challenging to start, and it would not go very fast when used. And in the worst cases, if the spark plugs are full of oil deposits your forklift won't start. If it is the cause, it is recommended to check the mechanical condition of the forklift and replace the spark plugs with new ones.
  • A defective forklift ignition coil will result in an engine failure. Difficulties with starting up can recognize the failure of an ignition coil. The batteries are drained rapidly, and the vehicle only starts after several attempts. Once you realize that your forklift is suffering from this problem, you should find out if the ignition coil must be replaced. To find it out, you should measure its resistance with your multimeter. The defective ignition coil will result in a lower resistive value than the normal one.
  • Other ignition system components such as the condenser, cap, rotor, or coil wires should also be inspected and replaced if required to avoid any future damage.
Hyster 2.5 XT engine
View of a Hyster 2.5 XT engine


Based on the simple explanation of how a petrol engine works, compression is needed to activate the ignition of petrol vapors. If there isn't enough pressure in all cylinders at the same time, then it won't start properly, or the combustion will happen too early.For that reason, that compression must be checked to ensure the engine will function properly after it has been serviced or repaired. If there is no relevant pressure in some cylinders, these cylinders need the replacement of the piston rings, cylinder liners, or other components.

Fuel system

The fuel system in a forklift is designed to draw diesel or LPG from the tank, blend it with air in the correct ratio in the inlet manifold, and push it into the cylinders where it can be burnt. Fuel-burning generates power that moves the piston down inside its cylinder, producing rotational motion at the crankshaft. This rotational motion is then transferred via the flywheel to the transmission and eventually to the forklift wheels.

First, check if fuel is reaching any part of the system by checking if the fuel filter is clogged or if there is a leak in any part of the system. To continue with inspection, other fuel system components that must be tested are the shut-off valve, fuel regulator, and the tank connector (for LPG Forklift). The test of these forklift parts is carried out by using special tools. In case any part is defective, replace it and test the forklift.


The first step when you suspect that the starter is at fault is to check out the battery. If this is completely flat and the leads are dirty and showing signs of corrosion, then this will need replacing immediately.

To tell if it's the starter, you can take a look at the terminal ends. If there is a build-up of grime and corrosion around them, then the problem might be the solenoid, or it could even be something as simple as a loose connection. You'll need to inspect these forklift parts for any wear and tear that might have occurred over time.

However, the best way to check if this is the problem is to take it apart and see what's going on. This might be a tad too complex for most people, so it is recommendable for a professional to test it. Is your Forklift starter failing? check this article.

Toyota Forklift Engine 4Y
Toyota Forklift Engine 4Y

Lift Parts Warehouse: A trustworthy Forklift Parts supplier

When it comes to finding a high-quality supplier for your forklift, there is simply no better choice than Lift Parts Warehouse. With the company's great prices and lightning-quick shipping times, you'll wonder why you hadn't ordered from them sooner. Visit our engine parts section today.

The company’s staff are professional forklift parts consultants who are extensively trained to help customers find the perfect part for their machine. They can answer any questions you may have about the safety and compatibility of the engine parts needed for your forklift.


A forklift will not start for a variety of reasons. The most common reason is that the battery is without charge. Other causes can be an aging battery, problems with ignition system components, low compression, or a faulty fuel system. If your Forklift Engine does not start, it's important to troubleshoot and find the root cause of the problem so it can be fixed. Lift Parts Warehouse is a trusted supplier of Forklift Parts and accessories. We have a wide selection of products from top brands at competitive prices. Let us know if you need help finding the right part for your machine.