Lawn Mower Starts Slowly

When you have a hard starting or slow starting lawn mower, the engine begins to turn over slowly and then it finally gets up to speed. This is a sign that the lawn mower is developing an engine problem and it should be checked out as soon as possible. If not, you will have a lawn mower that does not want to start up.

If your lawn mower doesn’t start, well, you won’t be getting much grass cut today! There could be many different things that prevent your lawn mower from starting normally. The grass could be clogging it up if it is a self-propelled or push lawn mower or your could have a carburetor choke problem that is giving you a slow start.

Check both of these items to ensure that you the choke is closing when you try to start and that there is nothing slowing down the lawn mower blades or the PTO shaft on a riding lawn mower.

The choke should gradually open if it is an automatic choke as the engine is starting. If it does not and hangs in the closed position and you see black smoke coming from the exhaust, the choke is definitely the problem here.

My Lawn Mower Is Hard To Start

Lawn mowers can be finicky machines. They can be easy to start one day and hard to start the next. In most cases it is a simple adjustment to make them easier to start.

This adjustment is often a valve adjustment. Over time the valve clearance become loose and will not allow the valves to open properly. If the intake valve does not open fully, a fresh charge of gasoline will not make it into the combustion chamber. If the exhaust valve does not open fully, the hot gasses will not be expelled out the exhaust pipe and it prevents fresh gas from coming into the combustion chamber as well.

An engine is basically an air pump. Air goes in and air goes out. Whenever that cycle is interrupted, it makes it hard to start the engine. Try adjusting those valves to their proper specification and see if it makes a big difference in the starting of that engine.

You should also check to make sure that the choke is working properly. An engine choke is a butterfly type valve and you close in the carburetor. When it is closed, it creates more vacuum inside the carburetor and pulls more fuel through it and into the engine. If the choke is not closing fully, then fuel will not be adequate enough for a cold start operation.

By adjusting the choke and valves, you should have an easier starting lawn mower.

How to Start a Hard Starting Lawn Mower

You are struggling to start your lawn mower and you just feel like pushing it over the nearest hill…well that is, if you have a hill!

Lawn mowers can be a real pain if everything is not working properly and a hard starting one can be frustrating. So, let’s see if we can take some of that frustration out of it for you.

A hard starting lawn mower can either have a fuel issue, ignition or a mechanical one.


You can check if the lawn mower is getting fuel by trying to start the engine and then removing the spark plug after you stop cranking. See if there is any gas on the plug. If not, it could be a fuel delivery problem such as a plugged up carburetor or fuel filter.


You can also install a spark tester at this time to see if you have good spark.


A choke that will not fully close is another issue that causes hard starting. Engage the choke fully and make sure that is closes completely.

Improperly adjusted valves is another item that will cause hard starting. Check the valve clearances to ensure they are in specifications.

Low engine compression can also cause this problem.  Check for the proper PSI that your engine should have.

These are some simple things that you can check and see if you can resolve your lawn mower problem. Perform these steps and hopefully you will find the problem!