Foam or paper, and an engine number rather than a mower number

Replacement mower air filters, compared

A petrol mower breathes through a filter the size of a sandwich, and a clogged one is the most common reason a mower that ran last summer will not start this spring. The shelf is unusual on this site in one respect: the fits column names ENGINES, not mowers. Briggs & Stratton, Honda, EMAK, LCT and SABO units are fitted to machines sold under a dozen other brands, so the useful identifier is the engine plate on the side of the block and the original part number — 399959, 31749, 799579 and their kin appear throughout these listings — rather than the name on the deck. A buyer who searches by mower brand will find nothing; one who reads the engine plate finds a €6 part in five minutes. The type is the second question and there are only two answers. Foam filters are oiled sponge, washable, and fitted to the smaller engines; paper cartridges are pleated, not washable, and fitted to the larger ones, sometimes with a foam pre-filter wrapped around them. Cleaning a paper element with compressed air ruins it, which is the mistake that costs an engine. The dimensions matter because several listings sell a shape rather than a part number, and a filter that is five millimetres short seals against nothing. The pack is worth reading too: these are sold in twos and threes at barely more than the price of one, and one is fitted while the other soaks. We compare type, dimensions, fits and pack.

Every part here, laid out figure by figure

1. 

   Green Star 27698

   Seven original references replaced and all three dimensions in the title — the cheapest filter here and the best documented.

   Type

   Not published as paper or foam

   Dimensions

   133 × 114 × 25 mm, as stated

   Fits

   Five named engine and machine brands; replaces seven original references, printed in full

   Pack

   1

   Amazon reference

   B093CCVFYT (one reference across 6 Amazon marketplaces)

   EAN

   3582321903521

   • Seven original part numbers listed, and three dimensions — both ways of checking
   • The cheapest filter on this shelf
   • The element material is not stated, so how to clean it is unknown

   Best for: Anyone whose old filter carries one of the seven references, or measures 133 × 114 × 25 mm

   Check price on Amazon
2. 

   L&S Engineers 30-710

   One line of description, three dimensions in the title, and four original references — for 3 to 6 PS engines.

   Type

   Not published as paper or foam

   Dimensions

   132 × 113 × 20 mm, as stated

   Fits

   Engines of 3 to 6 PS from one named maker; replaces three references and is stated to fit three further machine brands

   Pack

   1

   Amazon reference

   DE B0051ODOEO · US B0051ODOEO · GB B0051ODOEO · FR B0051ODOEO · IT B0051ODOEO · ES B08R7FRNN7

   EAN

   0826389832083

   • The dimensions are in the title, where a buyer with a ruler will see them
   • A power range — 3 to 6 PS — which is how these engine families are actually described
   • A single line of description and nothing else

   Best for: A small petrol mower with a 3 to 6 PS engine whose old filter measures 132 × 113 × 20 mm

   Check price on Amazon
3. 

   ZLKSKER 17211-ZL8-023

   A pleated paper element with a metal mesh, for a long list of Honda engines — and a dimension given in inches.

   Type

   Flat pleated paper element with a metal protective mesh and rubber, as stated

   Dimensions

   5.20 × 4.40 × 0.8 in, as stated by the maker

   Fits

   A long list of named engines, cultivators, pumps, generators and mowers across several brands

   Pack

   1

   Amazon reference

   B07V3GWXT2 (one reference across 6 Amazon marketplaces)

   EAN

   0611355720682

   • The element construction is described — pleated paper, metal mesh, rubber
   • Explains why the pleating matters: more area, less intake resistance, more dust capacity
   • The dimensions are in inches where the rest of the shelf uses millimetres

   Best for: A Honda-engined mower, cultivator, pump or generator matching one of the listed references

   Check price on Amazon
4. 

   Briggs & Stratton 491588S

   The engine maker’s own cartridge, naming four engine series — and telling you to check the manual before buying.

   Type

   Pleated paper with a flat filter plate, as stated

   Dimensions

   Not published — only packaging dimensions are given

   Fits

   Selected engines of one named series plus four further named series and numerous others

   Pack

   1

   Amazon reference

   B0011WP4Q6 (one reference across 6 Amazon marketplaces)

   EAN

   0004915880009

   • The engine manufacturer’s own part, identified by its own reference
   • States the element type — pleated paper with a flat plate
   • The filter’s own dimensions are not published — only the packaging

   Best for: An engine from one of the named series, where the original part is preferred to a copy

   Check price on Amazon
5. 

   SWNKDG 2× Luftfilter 550E/575EX

   Two filters at 112 × 69 × 37 mm for three named engine series — with an internal reference that belongs to another product.

   Type

   Not published as paper or foam

   Dimensions

   About 112 × 69 × 37 mm, as stated

   Fits

   Three named engine series from one maker; replaces three references

   Pack

   2

   Amazon reference

   B074CZZDXT (one reference across 5 Amazon marketplaces)

   EAN

   0761330039367

   • Sold as a pair, which suits a part changed every season
   • Three dimensions published, and they are unlike anything else on this shelf
   • The catalogue reference on the product record is for an unrelated product — this page prints it as found

   Best for: One of the three named engine series, buying two seasons at once

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6. 

   Hippotech 496894 / 496894S

   A filter and a foam pre-filter together, for 12.5 to 17 PS single-cylinder engines, with two separate reference lists.

   Type

   Filter cartridge with a separate foam pre-filter

   Dimensions

   Height 3 in, length 7¼ in, width 2 3/16 in at the narrow end and 2 7/8 in at the wide end, as stated

   Fits

   12.5–17 PS single-cylinder engines, with twelve engine designations named; references for two further brands given

   Pack

   1 filter and 1 pre-filter

   Amazon reference

   B07TZ5D6PH (one reference across 6 Amazon marketplaces)

   EAN

   8414745634109

   • A pre-filter included, and its own references listed separately
   • A tapered shape described with both widths — unusual precision
   • Dimensions in inches and fractions, where most of this shelf uses millimetres

   Best for: A 12.5 to 17 PS single-cylinder engine — a large machine rather than a push mower

   Check price on Amazon
7. 

   Easyboost EB497-525

   Two foam filters with the widest cross-reference list here — and the only listing that states which neighbouring housing sizes it also fits.

   Type

   Foam, as stated

   Dimensions

   132 × 114 × 22 mm, stated also to fit slots of 133 × 114 × 20 mm and 130 × 112 × 20 mm

   Fits

   Two engine makers by family, fourteen machine brands named, and original references for eight further brands

   Pack

   2

   Amazon reference

   B0BYPLLJQG (one reference across 5 Amazon marketplaces)

   EAN

   3701333904610

   • States the element is foam, which answers the cleaning question
   • The only listing here that names the neighbouring housing sizes it also fits
   • No statement about whether the foam should be oiled after washing

   Best for: A Honda or Briggs-engined mower or cultivator, where the exact housing depth is uncertain

   Check price on Amazon