Are Lawn Mower Engines Interchangeable? {Helpful Tips}

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If you own a lawnmower and your engine isn’t working properly, you will ask whether you can change the engine of your mower or not.

Well, the answer is not so straightforward. It depends on the type of mower you own.

If you own a riding mower, then the answer to your question is YES! Your riding lawn mower engines are interchangeable.

But if you own an electric mower then, it’s a NO. Electric mower engines are not interchangeable.

Let’s dig a bit into which lawn mower engines can be replaced and which cannot.

Are Lawn Mower Engines Interchangeable?

Are Lawn Mower Engines Interchangeable?

Riding lawn mower engines are interchangeable since they have the same bolt pattern. Some things may vary according to your mower such as 

  • Procedure to attach the throttle cable
  • The harness is composed of wires.
  • The position of the gasoline line and the in-line filter.
  • The connection between the starter and the engine.
  • The blades are spun by a pulley system that propels the mower.

Whereas engines of electric lawnmowers cannot be interchanged.

You’ll be Ok if you acquire a new electric engine that is identical to your old one. 

Otherwise, ensure sure any prospective replacement engine’s dimensions and mounting bolt spacing match the existing one.

How To Change Lawn Mower’s Engine?

There are some steps you need to follow to swap the lawn mower engine.

Before that, you should have knowledge of how an engine works in a lawn mower to make the process much easy.

Follow this step-by-step procedure and you will be all right

  • Put your parking brake on. The belts tugging on the drive train may loosen as a result of this. Sometimes it’s not the case.
  • Raise the mower’s front end. This guarantees that all of the gas returns to the tank. Just in case, have a spill kit on hand.
  • Disconnect the carburetor’s gas supply line. Any remaining gas should be drained into a clean container.
  • Remove the throttle line from the system.
  • Remove the starter from the circuit. It’s not a good idea to pull it out. Simply cut the cables that lead to it. This will only be available on key start systems. Engines that start using a pull start will not start.
  • Remove the engine mountain bolts by unscrewing them.
  • Remove the engine from the vehicle.
  • Then remove the crankshaft from the engine.
  • Connect the new engine’s crankshaft.
  • Place the new engine on the engine mounts. Don’t tighten anything; keep things loose.
  • Reattach the belts to the pulleys on the crankshaft.
  • Tighten the mounting nuts if necessary.
  • Connect the starter to the battery.
  • The throttle line must be connected.
  • Then connect the gas line.
  • As needed, fill the gas and oil tanks.
  • Start the new engine and put it to the test.
Changing lawn mower engine

When Should You Change Your Engine?

Engines for lawnmowers should last 1,500 hours on average.

If you mow your lawn once a week for six months and it takes you an hour to do so, your lawnmower should last 62 years at that pace, or almost as long as you’ll be in the house.

However,  you need to replace the oil and air filter whenever it is required.

Often poor blades of the lawn mower can put more pressure on the engine and lead to swapping lawn mower engines sometimes. so make sure to sharpen your blades using sharing tools.


Now you know how to change your mower’s engine. But before changing it, question yourself, does it really need to be changed? 

Look out for some symptoms, like if your engine is emitting smoke or your machine is not running smoothly and sputters.

Changing an engine may cost you more so make sure to follow the proper steps to maintain the lawnmower to extend the life expectancy of the engine.

If it really needs to be changed, then just follow the instructions provided above in this article. Or if you don’t want to indulge in this work, then you can always take a mechanic’s help.

About Tom Reynolds

My name is Tom Reynolds, and I like lawn mowing. When I was a kid, I used to help my dad in cutting grass using a reel mower, now, I have my own 6 different lawn mowers. Keeping my lawn healthy and beautiful gives me satisfaction, and I still enjoy working in my lawn.