Let Your Engine Breath – the Differences in Small Engine Air Filters

We’ve discussed keeping an eye on your engine’s air filter in the past, but we’ve never really gone in depth as to the functioning of an air filter, the types of air filters available and the differences in some of these air filters. Today, we’ll change that.

What Exactly Does the Air Filter Do?

When air gets pulled into the engine, it pulls in debris and particles as well. To keep this debris from making its way into the engine and clogging up the combustion chamber, the air filter traps everything in its element. The most efficient way that manufacturers have found is to have a removable, disposable filter.

What Types of Air Filters are Available?lawn mower air filter

There are three general types of air filters available for lawn mowers – foam filters, paper filters, and dual-element filters that feature both foam and paper. The dual-element filters feature a pre-cleaner element and the primary element. Dual-element filters will be more expensive, but will have longer life spans.

How Often Should you Replace your Air Filter?

An air filter needs to be replaced every 25 hours or so. Some manufacturers will recommend replacing the filter every 3 months, but that’s far from necessary. Particularly as some months may require more mowing than others, it’s really the hours that matter. Also, if you shake out your filter periodically, you can stretch the life span out another 5-10 hours.

Dual-element filters justify their expense in that they can get up to 100 hours of mowing time in before they really need to be changed. They will require changing or cleaning the pre-element every 25 hours or so.

What Happens if you Don’t Replace your Air Filter?

An air filter that is clogged, or full of debris, will reduce engine performance and engine power, which will make using the lawn mower a bit more tedious. Reduced power can also make for poor grass cutting, leaving a ragged finish or causing the engine to seize up when having to deal with high or thick grass. Worse yet, it can cause your mower to not start when you need it, and can lead to a shortened engine life.

How Difficult is it to Replace an Air Filter?

It’s not hard at all, actually. Most of the time, the owner will only need a few hand tools and ten minutes or so to remove the old filter and clean it, or remove it and replace it. Each mower is different, so make sure you check your owner’s manual for anything specific for your model. You’ll be best off looking for an Original Equipment Manufacturer (OEM) part that is identical to the existing air filter in your machine, to make it easier and faster to replace – you won’t have to worry about having to wiggle an oddly-sized replacement in.

When it comes down to it, air filters are pretty inexpensive, with most running in the range of $5 to $20. Particularly if your air filter is on the low end of the range, there’s no reason to risk the function of your lawn mower over a part that is less expensive than your lunch.

About AndrewT

Written by Andrew T for LawnEq - The specialists for Lawn Mower Parts and Small Engine Parts. We offer genuine premium OEM parts for Land Pride, Toro and many more dependable brands.