Everyone’s patch of lawn is their pride and joy. It’s almost seen as a status to have immaculately manicured grass. One defining factor that affects the quality is whether or not a lawnmower is used and used effectively.
The problem is, they are easily ruined if not maintained correctly, especially the engine. The simplest way to check out the engine’s condition is by first having a listen out for knocking, rattling and sputtering sounds.
Now let’s face the question, are lawn mower engines interchangeable?
Yes, the good news is that the lawn mower engines are widely interchangeable. Most models within a power range even have the same bolt pattern.
An old engine with the same power range can be unbolted, removed then changed over to one with a similar power range.
Luckily, we have laid the groundwork for you and laid it out in a simple understanding guide so you can walk away without further questions. Let’s dive deeper into if lawn mower engines are interchangeable and how they can be achieved.
Table of Contents
How do I know if my lawn mower engine is bad?
The signs of engine wear will start to become more prevalent with time. In fact, some apparent signs can help you determine if your lawn mower engine needs maintenance or a changeover. The signs may include:
- Knocking sounds or even rattling and sputtering. It can even screech when attempting to start.
- There may be excessive vibrations.
- You may see and smell smoke coming from the exhaust.
- You may notice that it is chewing through a greater than normal amount of oil and fuel
- It can shudder on heavy grass. It may even be just ineffective in general.
- It’s inconsistent and may just be difficult to get started. It may not even start at all.
Do all lawn mower engines have the same bolt pattern?
Most common lawn mower brands have the same engine mounting bolt pattern.
It can’t be said that every single engine is the same because there are always brands that produce things with the thought of cutting costs. This can see some being a little bit different.
But across the board, you will find it easy to change a motor without messing around with bolt patterns.
Are lawn mower engines interchangeable?
Lawn mower engines are interchangeable. The process isn’t too difficult to perform yourself. Of course, it’s advised that a qualified technician in the mechanical field changes it over for you, though.
The engine mounting points are often standard and don’t pose many issues with sourcing and installation.
Lawn mowers are great pieces of equipment in that the rest of the mower might be in immaculate condition, and just changing out the engine will almost make it an all-around brand new lawn mower. The costs involved will always depend on the quality of the lawn mower, to begin with.
How much does it cost to replace a lawn mower engine?
Considering the engine of a lawn mower is the most important part, it will always be the most costly. Replacing a lawn mower engine and the costs involved will largely depend on the type, size and availability of the new one.
Generally speaking, the labor costs can range between $90-$150 per hour, depending on the mechanic.
The changeover shouldn’t take longer than 2-3 hours, so that’s a max of $450 on labor, then you have the cost of a motor. They can range from $250 anywhere up to $1800. Another thing to consider is that the engine can be for a push mower or ride-on. Ride-ons are larger, so they will cost a lot more.
Is it worth replacing a lawn mower engine?
It is definitely worth replacing a lawn mower engine. A bit of common sense and personal preference will come into play here. If the engine needing replacement is quite old, it’s worth it. If it’s a newer engine, it’s a good idea to have a mechanic check over it first to save money, time and convenience.
Sometimes even a drive belt or another smaller part connected to the engine could need changing out instead of the whole engine. The great thing about lawn mowers is that they are easy to get a hold of the parts and the actual engines.
The bolt patterns are standard, so changing them can be seamless. Additionally, as we progress through technology upgrades, you can pick up a newer, more advanced modeled engine for that little bit extra. That way, you get a new lawn mower without purchasing the whole thing.
Types Of Lawn Mower Engines?
When thinking about changing the engine in your lawn mower, we often think about the common push mower. Similarly, the ride on is another type of mower engine that could need replacing. They both work in the same way; they are both internal combustion-type engines.
One is much larger than the other, so it may cost some more to fix. Let’s have a look at the 2 compared to each other.
Riding lawn mower engines
The engines used on a ride-on are usually 4 cylinder variants. 4 stroke engines offer much more torque and are much more fuel efficient. They are easier to start, more powerful and reliable.
The only real downside is that they are more expensive to run. The benefits outweigh this one downside, though. Most riding mower engines are interchangeable with each other.
Electric mower engines
Standard electric mower engines or ‘push mowers’ usually run on 2 cylinders. 2 stroke engines are generally cheaper overall. This is because they are a lot smaller and weigh much less. They are also louder and produce more smoke. Most electric mowers are interchangeable with each other.
Lastly, it’s not ideal to put an electric mower engine into a ride-on lawn mower as it just wouldn’t offer enough torque to push around the weight of a ride on. On the other hand, you could add a 4 stroke engine to a push mower. You would need to make a few extra modifications, though.
Things to consider before Are Riding Lawn Mower Engines Interchangeable?
If your ride on lawn mower engine shows signs of excess wear and tear, it may need to be replaced. It’s generally a pretty easy procedure for the right mechanic. They will usually know what to look for as they will do the changeover for you.
There are some things to consider if you plan to do it yourself. For example, some parts and accessories must be double-checked to ensure that the new engine fits on the old deck. The main parts and accessories that you should take note of are:
- Matching nuts and bolts – These are easy to skip over, but they hold it all together.
- Throttle Cable – Make sure the right connection is available and/or purchased so that it can all be connected once the engine is in.
- Lawn Mower Blades – The lawn mower blades should either be new or well maintained. It’s ideal for sharpening them after every 4-5 uses.
- Fittings in the crankshaft – Ensure that the fittings are the correct size for the new engine. The crankshaft needs to be running at optimal speed and pace.
- Matching sizes of pin holes – The pin holes must be the right size, or the engine won’t even mount, let alone start.
- Fuel Lines – The fuel lines should be clean and well kept. Try to flush them out before reinstalling to avoid any blockage causing debris.
- Starter connection to engine – This should be one of the last things you reattach, so ensuring it’s clean and in working order is essential.
- Wiring, Clamps and Hoses – All wiring, clamps and hoses should generally be cheap, so it’s almost worth buying new ones. This will ensure that the installation process runs smoothly. Some older parts can be jagged and unkept.
Some Easy Steps To Change a Riding Lawn Mower Engine
It’s probably best to have a mechanic changeover the engine in your ride-on lawn mower. If you are one to endure a challenge, though, the process isn’t that difficult. It goes a little something like this:
- Source a similar-sized engine. Make sure the power is like for like.
- Remove the motor mount bolts and pull attached to the engine shaft (usually found under the engine)
- Lift the engine cover/hood and disconnect the lighting wires
- Completely remove the engine cover, so it’s not in the way. You should be able to pull it upwards.
- The next part will require some kind of jack or lift to raise the front end. It makes it easier to remove the motor mount bolts and pulley bolts.
- Tip* Putting the parking brake on will help loosen up the drive belt.
- Slide down the top belt (above the pulley)
- Pull down the unbolted pulley to release the lower belt.
- Remove the motor engine mount bolts. (usually 4) There may be a hidden bolt depending on the model.
- Tip* Keep the fuel line higher than the fuel tank; the fuel won’t leak.
- Disconnect the fuel line
- Remove the starter motor wire.
- Disconnect any other wires to free up the engine. There may be a few zip ties that need to be cut.
- The engine should now be free to lift out.
- Before installing the new engine, give the mounting surface a good clean.
- Some new engines come without the holes being threaded for the mounting bolts. You may need to tap new threads to suit the bolts. Lubing the holes will allow the taps to do their thing more easily.
- Connect everything back together in reverse order, including bolting down the engine and connecting all wires and clamps over hoses.
- Run the fuel and oil in before use.
- Enjoy
Frequently Asked Questions (fAQs)
What is the most common lawn mower engine?
Ride on lawn mower engines is often 4-cylinder or 4-stroke. They are much larger, more effective, and more expensive but, on the other hand, more robust. Compare that to the 2 cylinder variants usually used on push mowers. Push mowers are often much louder and smaller, so they weigh less, but they are also much cheaper.
How long should a lawn mower engine last?
The length of time that a lawn mower can last depends on a few specific factors. Things such as engine quality, frequency of use and maintenance play a huge role in the longevity of a lawn mower engine. Using it as normal as possible with a proper maintenance schedule will allow around an 8-10 year lifespan. For a smaller engine, that would be about 300 to 500 hours. The larger engines may push on up towards 750 to 1000 hours.
Are Briggs and Stratton engines interchangeable?
Most mower engines are universal these days. Briggs and Stratton are no different and can be interchangeable if needed.
Conclusion:
So as we can see, most lawn mower engines are interchangeable. There may be an odd exception depending on the brand, but most brands are universal. A push mower usually has less power and is louder but can be much cheaper.
Riding lawn mowers have much more power, can cover more ground, and are more reliable but cost more to run and maintain. Changing over the engine isn’t always necessary, depending on the issue that needs to be resolved. If a changeover is needed, at least we know it’s not a tough task!
