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HomeRepair HelpRyobi Mower RepairRyobi Lawn mower is hard to start Repair
Ryobi Lawn mower is hard to start
If your Ryobi lawn mower is hard to start, the problem is usually in the fuel system first, especially a clogged carburetor caused by old gas sitting too long. Sticky fuel residue in the carburetor or carburetor float bowl can make a lawn mower difficult to start or cause a mower hard starting condition that takes many pulls to fire. Start by cleaning the carburetor with carburetor cleaner. If that does not fix it, a carburetor repair kit or a complete carburetor replacement may be the better move. Next, check the primer bulb, since a cracked bulb can pull air into the fuel system and make the engine hard to start. Old or bad gasoline is another common cause, so draining stale fuel is often worth doing before replacing parts. If the fuel system checks out, inspect the spark plug for wear, carbon buildup, or a cracked insulator, and use a spark plug tester to confirm strong spark. On models equipped with one, a weak fuel pump can also make a Ryobi lawn mower hard to start. Enter your model number on RepairClinic.com to find the exact replacement part for your mower.
01 - Ryobi Lawn Mower Carburetor
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the hedge trimmer for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and make the engine hard to start. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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02 - Ryobi Lawn Mower Primer Bulb
Over time, the rubber of the primer bulb can become brittle and cracked. If the primer bulb is cracked, air will get into the fuel system and cause the engine not to run properly. If the primer bulb is cracked, replace it.
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03 - Ryobi Lawn Mower Carburetor Repair Kit
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the hedge trimmer for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and make the engine hard to start. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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04 - Old or Bad Gasoline
There may be old or bad fuel in the carburetor float bowl. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and make the engine hard to start. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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05 - Ryobi Lawn Mower Spark Plug
Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.
Highly Likely
06 - Ryobi Lawn Mower Fuel Pump
The fuel pump has three ports: the gas in port, the gas out port, and the pulse port. The pulse port is connected to the engine crankcase by a small rubber tube. As the engine runs, air inside the crankcase alternately pressurizes and depressurizes the air in the tube. This pressurized air moves a diaphragm inside the pump and pumps the gas. If the engine oil is overfilled, oil can enter the pulse port line, preventing it from working properly. The fuel pump also has two small check valves on the input and output ports. The check valves prevent fuel from reentering the gas tank. These check valves can fail. To determine if...
Highly Likely
Frequently Asked Questions
Why is my Ryobi lawn mower hard to start?
My Ryobi lawn mower takes many pulls to start. Should I clean or replace the carburetor?
Can a bad spark plug make a Ryobi lawn mower difficult to start?
How do I know if the primer bulb or fuel pump is causing my Ryobi mower hard starting?
How do I find the right Ryobi lawn mower part for a hard-start problem?
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