In Lawnmowers and tractors, a PTO, or power take-off component, transfers the mechanical power from the engine to all the other accessories and attachments. The engine should run smoothly with an engaged PTO when everything is well with the machine.
So if your lawn mower engine dies when the PTO is engaged, there is something wrong with this component. Unfortunately, this does not happen due to a problem with the PTO clutch or switch alone. It could be related to the fuel system, a bad battery, a faulty spark plug, or even plugged filters.
This blog post sheds light on this problem and discusses troubleshooting methods. So stay tuned for proper insight.
Why does your Engine Die when PTO is Engaged?
Table of Contents
With so many culprits involved in this issue, you might think solutions are complicated. However, most causes are easy to handle, especially when diagnosed correctly. Many problems with the filter or fuel lines can be avoided with ongoing, regular maintenance.
1. Poor Blades Adjustments
The mower’s blades are responsible for cutting the grass. The blade deck also acts as a protective cover for the engine and the rider from the sharp cutters. When engaged appropriately, you will experience smooth and successful cutting.
Blades usually disengage when the drive belt is damaged or broken. Disengaged blades are unable to connect to the PTO. This causes the engine to lose power suddenly.
2. Fuel System Problems
The simplest problem in the fuel system affects the PTO. This may end up making the PTO die and become unresponsive. First of all, the fuel levels might be insufficient. Also, thick gasoline sitting in the machine for a long time will eventually clog the system.
Eventually, the fluid won’t pass smoothly enough to reach the whole engine. This scenario will cause a starting failure in the engine despite the engaged condition of the PTO.
A faulty fuel cap contributes to the gasoline restriction. It may lead to dirt and debris accumulating inside the fuel system.
3. A Faulty Air Filter
The air filter allows clean air to flow smoothly into the engine. When this filter is clogged, the air will be restricted. This will make the machine unable to combust and subsequently run. Even if the PTO engages, the engine will not start.
4. A Problematic PTO
Most PTO problems are related to a bad PTO switch or a faulty clutch. This switch is supposed to increase the safety of a lawn mower. The switch is supposed to stop the motion of the blades. It can also start the blades once you hit the switch.
The engine can never start if there is a problem with the clutch or the switch. Also, the cutting blades will never spin. A faulty switch occurs when the PTO receives insufficient voltage or its compartments are worn and torn.
Additionally, a frayed PTO belt stops the engine suddenly despite an active PTO. With frequent use, the belt can get damaged or stretched out. As a result, there will be no connection between the engine and the cutters.
5. A Bad Battery
The battery gives the engine electrical power, contributing to its proper starting. However, when the battery malfunctions, the engine will fail. Regardless of the PTO engagement, the engine will always need the electric battery voltage.
Many problems can interfere with the battery, such as loss of charge, corrosion, or wear and tear in the battery wiring.
6. A Faulty Spark Plug
The spark plug in a mower is necessary for the ignition procedure. If the plug is not working, the motor misfires or fails. Its issues can be as simple as carbon buildup or loose spark plug wires. Usually, clean plugs perform their role and appear light gray instead of black or dark brown unclean ones.
7. Active Reverse Gear
Sometimes, a mower’s mechanical and electrical components work just fine. Still, the engine dies when the PTO is engaged without an apparent reason. In this case, revise the gear position. It might be set in reverse mode. This scenario will cause the tractor engine to fail to start. This is a typical safety feature in all mowing equipment.
How to Fix an Engine That Dies When PTO is Engaged?
You must address the responsible issues to correctly fix a mower’s engine that dies when the PTO engages. Sometimes, there is more than one cause for this irritating problem.
Still, if you handle the problem quickly, you will avoid severe damage to the engine crankshaft. Also, you will save your machine from an eternal engine failure that may call for replacing the whole engine.
1. Adjust the Blades Correctly
The blade settings are almost the same regardless of the different engine models. First, make sure the blades are properly sharpened and balanced. Then, review whether the blade length is compatible with the engine capacity.
Lastly, ensure that the blades are attached correctly to the deck. Doing so will eliminate the chances of the engine stalling due to incorrect blade settings.
2. Fix the Fuel Problems
As you know, fuel issues are multiple and concern different parts. So, it is vital to diagnose the source of the problem correctly. If you find a problem with the gasoline level, you should refill the fuel tank with fresh gasoline. Moreover, the tank should be refilled to the recommended levels without being filled too much or too little.
Also, search for clogs and deposits on fuel valves. Clean the buildup to guarantee the smooth flow of fuel throughout the engine. Additionally, replace the fuel filter if it appears out of shape.
3. Replace the Air Filter
If you are keen on this regular routine, a dirty air filter can be cleaned. However, cleaning won’t be helpful if you have a filthy filter. It is better to get a new filter. Air filters are found in all hardware stores and online shopping portals.
4. Fix the PTO
Diagnosing PTO clutch problems is relatively easy. The first sign is noticing some noise coming from the PTO shaft. Also, a functional clutch takes no time to engage, so it is a bad sign when it engages slowly. In case of a problematic PTO, you should thoroughly check its parts.
Start by cleaning the PTO clutch and ensuring it is not damaged. If there are signs of damage, then get a new one. You will need replacements if the lever or switch is no longer functional. If a proper diagnosis is not possible, consult an expert.
5. Replace the Battery
It would be best if you tried basic fixes before going for an entire battery systems replacement. This includes inspecting the battery for corrosion. This type of corrosion usually looks powdery and white. It is found on the battery’s surface. It affects the transmission of electrical current. You can easily scrape off the corroded buildup.
Also, check the battery wires for loose or torn connections. Try to fix or replace these wires based on their condition. Also, recharge the battery fully if it turns out to be dead.
6. Change the Spark Plug
You will need a new one if you see a damaged or cracked spark plug. There is nothing you can do to fix such plugs. You can try cleaning a dirty spark plug, but getting a replacement is easier and more effective.
7. Set the Gear in the Forward Position
This is one of the most manageable issues to troubleshoot in this situation. There are no replacements or complicated fixes required for this issue. You may set the gear back into the F or forward position. This can get the engine running just fine whenever the PTO engages.
Marvin is an expert in farming equipment with a strong background in agricultural engineering. He graduated from Kansas State College of Agriculture, where he received a degree in Agricultural Engineering and specialized in farm equipment design and maintenance.
