Troy-Bilt makes a series of outdoor power tools and yard care equipment. They are one of the most recognizable and trusted names currently in the industry. Their line of trimmers and mowers are particularly revered.
Sometimes, however, those things don’t start. So, what’s the reason behind the malfunction? Well, the list is long as to what the problem could be. Old or bad fuel, the fuel pump, the fuel filter, the ignition coil, the start switch, the carburetor, the spark plug, and a number of other things. Check our guide to see what the issue may be and how to resolve it.
Table of Contents
Bad or Old Gas
Believe it or not, the most likely reason for your Troy-Bilt mower not starting is due to old or bad fuel. When bad or old fuel gets stuck in the carburetor float bowl, some of the ingredients within can evaporate. When it does so, there is a stickier, thicker residue in its wake.
Remove the Old Gas
Allow the fuel to sit there and the bad fuel can clog up the carburetor. So, the first thing that you should do is check the quality of the gas. You should probably even just dump the fuel out and clean things out to be safe.
Directly related to a fuel issue is the fuel pump. There are three pumps to it: the pulse port, the gas out port, and the gas in port. The pulse port is what is directly connected to the crankcase of the engine using a small rubber tube. When the engine is running, the air that is in the crankcase will both pressurize and depressurize the air that is in the tube.
That pressurized air moves a small diaphragm that is inside of the pump, pumping the gas through the pump. When the oil in the engine has been overfilled, oil can then enter through the pulse line and prevent the fuel pump from working properly.
Why is the Fuel Pump Failing?
Those two ports – the input and output – are check valves. These valves are what prevent the fuel from going back into the gas tank. Those checks, however, can fail from time to time. When the fuel gets back into the tank, it can lead to clogs in the line that ultimately stifle the motor from running.
In order to determine the effectiveness of the fuel pump, check out those valves, the diaphragm that is located within the pump, and the pulse port line. Keep in mind that if you find anything wrong with any of those components, the entire fuel pump will need to be replaced as it cannot be repaired.
In any tool that makes use of a combustion engine, the spark plug is generally one of the primary culprits. Once you are certain that the fuel is not the issue (or have eliminated the fuel pump as a potential issue), move on to checking the spark plug.
1. Check for damage. Take a look at the spark plug for any signs of damage or excessive wear and tear.
2. Other signs of damage. If you notice that an electrode has been damaged or burned away, if there is heavy carbon buildup near the electrode, or the porcelain insulator is cracked or broken, the spark plug should be replaced immediately.
3. Test the spark plug. Should you not notice signs of external damage, test the spark plug using a spark plug tester. If the spark plug is working properly, you will notice a strong spark between the terminals of the tester as the engine cranks.
4. Replacing the spark plug. Failing to see a spark is a good indication that the spark plug isn’t working effectively and should be swapped out.
Check the Carburetor
Another common issue in combustion engines is the carburetor. While they don’t typically “break down”, they can become clogged over time. That fuel issue mentioned a few sections above typically impacts the carburetor as well as the fuel pump.
When fuel sits unused over time, it will begin to evaporate and leave a sticky substance in its wake. That sticky substance can eventually clog the carburetor, preventing the engine from starting at all.
1. Check for that sticky substance. First, check the gas tank and carburetor for dried, sticky fuel.
2. Clean the carburetor. Thankfully, there are carburetor cleaners that are specifically created for such a purpose.
3. Rebuild or replace. If, after cleaning the carburetor, it still isn’t working properly, you will have to rebuild or replace the carburetor entirely.
The Start Switch
After checking the more common culprits, it is worth checking on the start switch. The start switch is what you would press prior to pulling on the rewind pulley. If the switch is defective, you won’t be able to properly start the mower.
The first thing that you should do if you think that the start switch is bad is to get a multimeter (if you don’t have one). A multimeter will help you to test a variety of components not only on the mower but other tools like trimmers, leaf blowers, etc.
The role of the ignition coil is to send the proper amount of voltage through to the spark plug while the engine is operational. When the ignition coil is defective, it can’t send voltage to the spark plug. And when that happens, the engine won’t be able to start.
Check to make sure that the ignition coil is working properly before automatically assuming that it is defective. Also, make sure that the spark plug is working properly. If it is, test out the ignition coil using an ignition coil tester. If the ignition coil has gone bad, replace it and you should be good to go.
The Flywheel Key
The flywheel key, a small piece of metal that fits into the crankshaft, is what engages with the flywheel itself. You may notice that your lawnmower stops working after hitting a particularly big or hard object.
When this collision happens, it is a pretty good indication that the flywheel key has either broken or completely sheared in half. When the flywheel key has been damaged or broken, the lawnmower will not start normally if at all.
Checking the Flywheel Key
To check whether or not the flywheel key has been broken, take the flywheel off of the engine entirely to inspect the key portion. The easy part of this is that the flywheel key will either be broken or it won’t. If it is, replace it as soon as possible.
The Recoil Starter
By now, you’re pretty deep into the troubleshooting process. The unfortunate thing is that, even though there are a few general causes for your mower not starting, there are still a lot of possibilities that need to be checked.
The recoil starter in particular isn’t a common issue, but it is what engages the crankshaft to eventually turn the engine over. When the recoil starter isn’t working properly, it can’t engage the crankshaft and turn the engine over to start.
1. Remove the assembly Take out the assembly entirely and give it a good look over. Any damage could be an indication that the recoil starter is bad.
2. Test the assembly. Generally, it should work by extending tabs from the pulley and cam that will grab onto the hub on the engine. This is what makes the engine turn.
3. Retract the assembly. When the recoil starter is working properly, not only will it turn over the engine, but the tabs should retract when you release it. The rope should then wind back up onto the pulley.
4. Replacing the assembly. When it stops working properly, you’ll have to replace it entirely.
Rewind Pulley and Spring
The rewind pulley and the recoil starter are basically how you start up the mower. When those become compromised in any way, the engine won’t be able to turn over properly and the mower can’t start. If you have worked through troubleshooting methods to this point and turned up empty, the rewind spring itself could be broken.
When you pull the starter rope and release it, the rewind spring will recoil the starter rope back onto a pulley. Should the spring break, the rope can’t recoil back onto the pulley and the engine can’t turn over effectively.
Replacing the Rewind Springs
Most rewind springs, when broken, can be replaced individually. Still, it is best to check out the entire spring and pulley assembly for any potential damage. You might get lucky and be able to replace the spring without having to replace the entire assembly.
Is Troy-Bilt a Good Mower Company?
According to customer reviews, Troy-Bilt is not only well planned, but quite well built as well. For the most part, their line of mowers is dependable and quite tough, capable of holding up against even tall grass on a regular occasion.
Troy-Bilt equipment is built to last. Still, some preventative maintenance will go a long way towards preserving the condition of the mower.
Providing Proper Care
Make sure to properly clean your mower on a regular basis and don’t leave fuel in the tank for more than a few weeks at a time. As covered previously, old fuel can wind up clogging up various components of the mower, preventing them from working at all.
Investing in a Troy-Bilt mower is a good idea for giving your lawn the proper care that it deserves. Making matters easier is that, when a component breaks down, finding replacement parts or having work done is relatively painless.