Generator maintenance kits simplify routine service, but the right choice depends on your generator’s exact model, engine, and service needs. My best overall pick is the Generac 6484 Scheduled Maintenance Kit for 12–18 kW standby units, while the Generac 6485 kits stand out for compatible 16–26 kW models and the Kohler GM90366 offers a brand-specific alternative. The biggest tradeoff is between a kit matched closely to your generator and a lower-cost or broader-fit option that may not include the parts your service schedule calls for. Liquid-cooled engines and smaller PowerPact models also need their own fit-specific kits. Read on for the full comparison, selection criteria, and buying advice.
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Key Takeaways
- Generator and engine compatibility is the first filter: the lineup separates into air-cooled, liquid-cooled, PowerPact, and Kohler-specific options, so wattage alone does not confirm fit.
- Generac 6484 and 6485 kits appear in multiple listings: compare the stated generator range and engine details rather than assuming similar part numbers or titles make them interchangeable.
- Large 999cc generators have several listed kit choices: the 5W-20, 6485, and 0J93230SSM options make exact model and service requirements especially important.
- Liquid-cooled units need a separate fit check: the Generac 5655 and 5656 are designated for different engine displacements, unlike the air-cooled kits dominating this roundup.
- Brand-specific fit beats a broad category match: the Kohler GM90366 is the only Kohler entry, while most options are designed for particular Generac families.
| 6484 Scheduled Maintenance Kit for Generac 12–18 kW Standby Generators |  | Best Overall for 12–18 kW Generac Owners | Model: 6484 | Compatibility: Generac 12–18 kW standby generators with 760–990 cc engines | Oil filter: 070185E, 070185ES | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 5664 Air-Cooled Standby Generator Maintenance Kit |  | Best for Older Generac Models | Model: 5664 | Compatible generator output: 13–17 kW | Compatible engine: 760/990cc Generac OHVI | VIEW LATEST PRICE | See Our Full Breakdown |
| KOONDHEEND 6485 Maintenance Kit for Generac 16–26 kW Air-Cooled Standby Generators | | Best Complete Kit for 999cc Guardian Models | Model number: 6485 | Compatible generator output: 16–26 kW | Compatible engine: 999cc | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 6806 Maintenance Kit for 7 kW PowerPact Standby Generators |  | Best for Compact PowerPact Systems | Model number: 6806 | Compatible generator: Generac 7 kW PowerPact standby generator | Engine: 420 cc | VIEW LATEST PRICE | See Our Full Breakdown |
| 6485 Maintenance Kit for Generac 16–26 kW Air-Cooled Generators |  | Best Filter-Only Replacement Pick | Model number: 6485 | Compatibility: Generac 16–26 kW air-cooled standby generators with 999 cc engines, 2013 or later | Replacement part numbers: 0062440, 0062500, 0062580, 0062620, 0062680, 0062770, 0062581 | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 5W-20 Maintenance Kit for 20–26 kW 999cc Generators |  | Best for an Oil-Included Service | Brand: Generac | Compatible generators: 20–26 kW, 999cc | Engine: Generac G-Force 999cc V-Twin | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 6482 Maintenance Kit for 8kW-10kW Standby Generators |  | Best for DIY Service Accessories | Manufacturer: Generac Power Systems Inc | Model number: 6482 | Compatible output: 8–10 kW | VIEW LATEST PRICE | See Our Full Breakdown |
| 6485 Maintenance Kit for Generac 16KW-26KW 999cc Air Cooled Generator |  | Best for Broad 999cc Model Coverage | Compatibility: Generac 16–26 kW air-cooled generators, 999cc, model years 2013 onward | Included components: 1 oil filter, 1 air filter, 2 RC12YC spark plugs | Oil filter part: 070185E | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 5655 Maintenance Kit for 1.6L Liquid-Cooled Standby Generators |  | Best for Liquid-Cooled Generator Service | Compatible engine: Generac 1.6L liquid-cooled | Maintenance interval: Every 200 hours or 2 years | Included components: Air filter, oil filter, 4 spark plugs, spark plug wrench, oil funnel, chamois, reminder sticker | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 6485 Scheduled Maintenance Kit for 20–26 kW Standby Generators with 999cc Engine |  | Best OEM Kit for Multi-Brand Compatibility | Compatible generator output: 20, 22, 24, and 26 kW | Compatible engine: 999cc V-Twin | Compatible build year: 2013 or later | VIEW LATEST PRICE | See Our Full Breakdown |
| Kohler GM90366 Generator Maintenance Kit |  | Best for Kohler Owners Who Want Oil Included | Brand: Kohler | Model: GM90366-SKP1-QS | Compatible generator: 12RESVL-100LC12 | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 0J93230SSM Maintenance Kit for 20–22 kW 999cc Generators |  | Best for a Specific 999cc Generac Fit | Brand: Generac | Model and manufacturer part number: 0J93230SSM | Compatible generator output: 20–22 kW | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 6484 Maintenance Kit for 12–18 kW Standby Generators |  | Best for Broad 12–18 kW Compatibility | Compatible generators: 12–18 kW air-cooled standby generators | Engine displacement: 760cc–990cc | Compatibility: 2013 and later Generac models; compatible Honeywell and Centurion models | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 5656 Maintenance Kit for 2.4L Liquid-Cooled Standby Generators |  | Best for Liquid-Cooled, High-Output Generators | Brand and model: Generac 5656 | Engine compatibility: 2.4L liquid-cooled generators | Generator compatibility: 25 kW low-speed and 45 kW 3600 RPM generators | VIEW LATEST PRICE | See Our Full Breakdown |
| Generac 5663 Maintenance Kit for 530cc HSB Generators |  | Best for Older 530cc OHVI HSB Models | Brand and model: Generac 5663 | Compatibility: Generac HSB models with 530cc OHVI engines manufactured from 2008 to 2012 | Included components: Air filter, oil filter, spark plug, oil funnel, chamois, instruction manual, maintenance reminder sticker | VIEW LATEST PRICE | See Our Full Breakdown |
| generator maintenance kit | Included components |
|---|---|
| 6484 Scheduled Maintenance Kit | — |
| Generac 5664 Air-Cooled Standb | Air filter, oil filter, oil funnel, spark plug, chamois, instruction manual, reminder sticker |
| KOONDHEEND 6485 Maintenance Ki | 1 × 070185E oil filter, 1 × 0J8478S air filter, 2 × RC12YC spark plugs, oil funnel |
| Generac 6806 Maintenance Kit f | — |
| 6485 Maintenance Kit for Gener | — |
| Generac 5W-20 Maintenance Kit | 1 air filter, 1 oil filter, 2 spark plugs |
| Generac 6482 Maintenance Kit f | Air filter, oil filter, spark plugs, funnel, wrench, chamois, reminder sticker, and instructions |
| 6485 Maintenance Kit for Gener | 1 oil filter, 1 air filter, 2 RC12YC spark plugs |
| Generac 5655 Maintenance Kit f | Air filter, oil filter, 4 spark plugs, spark plug wrench, oil funnel, chamois, reminder sticker |
| Generac 6485 Scheduled Mainten | — |
| Kohler GM90366 Generator Maint | — |
| Generac 0J93230SSM Maintenance | — |
| Generac 6484 Maintenance Kit f | — |
| Generac 5656 Maintenance Kit f | Air filter, oil filter, 4 spark plugs, spark plug wrench, oil funnel, chamois, reminder sticker |
| Generac 5663 Maintenance Kit f | Air filter, oil filter, spark plug, oil funnel, chamois, instruction manual, maintenance reminder sticker |
More Details on Our Top Picks
6484 Scheduled Maintenance Kit for Generac 12–18 kW Standby Generators
I’d put this kit first for owners of compatible 12–18 kW Generac standby generators because it covers more of a routine service visit than a filters-only set: it includes an oil filter, air filter, two spark plugs, an oil funnel, and a chamois. That combination is more complete than the Generac 5664, which is aimed at older 13–17 kW models and includes one spark plug. The practical tradeoff is narrow fit: the 6484 is specified for 760–990 cc engines, so output rating alone is not enough to confirm compatibility. I’d match the engine and replacement part numbers before ordering. This is a sensible all-in-one choice for scheduled upkeep, but oil is not listed among the included items, and installation still means handling service parts.
Pros:- Includes oil and air filters plus two spark plugs for a broader scheduled service.
- Adds an oil funnel and chamois for practical maintenance support.
- Specifies compatible 760–990 cc Generac standby engines.
- Includes a 1-year replacement warranty.
Cons:- Compatibility is limited to specified 12–18 kW models and engine sizes.
- Oil is not listed as included.
- Installation requires handling maintenance parts; gloves are recommended.
Best for: Owners of Generac 12–18 kW standby generators with 760–990 cc engines who want filters and both spark plugs in one routine-maintenance kit.
Not ideal for: Owners of other engine sizes or generator ranges, and anyone expecting the kit to include engine oil.
- Model:6484
- Compatibility:Generac 12–18 kW standby generators with 760–990 cc engines
- Oil filter:070185E, 070185ES
- Air filter:0E9371A
- Spark plugs:2 × RC14YC
- Included accessories:Oil funnel and chamois
- Dimensions:7 × 6.99 × 7 inches
- Weight:1.48 pounds
- Warranty:1-year replacement warranty
Our verdict“Choose this kit for a compatible 12–18 kW Generac if you want filters and two spark plugs together, but verify the engine fit and plan to supply oil separately.”
Generac 5664 Air-Cooled Standby Generator Maintenance Kit
The Generac 5664 earns a distinct place for owners of compatible air-cooled units made from 2008 to 2012. Its filters, spark plug, funnel, chamois, instructions, and reminder sticker make routine service more organized than the parts-only RARAYC 6485, which lists replacement air and oil filters but no service accessories. The reminder sticker and instructions are especially useful for owners who want a clear record of the next interval. This kit is specified for 13–17 kW generators with 760/990cc OHVI engines, so newer machines or similar-output models with different engines may not fit. The main limitation is that oil must be purchased separately; it also includes one spark plug, rather than the two supplied with the 6484 kit.
Pros:- Includes air and oil filters plus a spark plug for scheduled service.
- Provides instructions and a maintenance reminder sticker.
- Includes an oil funnel and chamois.
- Specifies compatible Generac 760/990cc OHVI engines and model years.
Cons:- Oil must be purchased separately.
- Compatibility is limited to specified 13–17 kW models and 2008–2012 manufacturing years.
- Includes one spark plug, fewer than the two in the 6484 kit.
Best for: Owners of compatible 13–17 kW Generac air-cooled standby generators manufactured from 2008 to 2012 who value included instructions and a service reminder.
Not ideal for: Owners of newer generators, other engine families, or buyers seeking a kit that includes engine oil or two spark plugs.
- Model:5664
- Compatible generator output:13–17 kW
- Compatible engine:760/990cc Generac OHVI
- Compatible manufacturing years:2008–2012
- Included components:Air filter, oil filter, oil funnel, spark plug, chamois, instruction manual, reminder sticker
- Oil:Not included
- Recommended maintenance interval:Every 200 hours or 2 years
- Weight:1.5 pounds
- Dimensions:5 × 5 × 5 inches
Our verdict“Pick the 5664 if your generator matches its older-model fit and you want service instructions and a reminder sticker, while accepting that oil is separate.”
KOONDHEEND 6485 Maintenance Kit for Generac 16–26 kW Air-Cooled Standby Generators
For a compatible 999cc Generac Guardian, this KOONDHEEND kit offers a fuller service bundle than the RARAYC 6485, which lists air and oil filters but not spark plugs or a funnel. Here, the included oil filter, air filter, two RC12YC plugs, and oil funnel cover several common maintenance needs in one package. Its stated fit spans 16–26 kW and names models such as the 7034, 7035, 7043, and 7141, giving buyers useful checks beyond the output range. Compared with the 6484 kit, this one targets the larger 999cc engine family rather than 760–990 cc units. It does not include oil, and compatibility still depends on the exact generator model. The kit also comes from a non-Generac manufacturer, so I’d verify part numbers against the owner’s manual.
Pros:- Includes oil and air filters, two spark plugs, and an oil funnel.
- Lists compatible Guardian models as well as the 16–26 kW range.
- States a 1-year replacement guarantee.
- Targets the 999cc engine family, unlike the 6484 kit for smaller engine ranges.
Cons:- Does not include oil.
- Fit is limited to compatible 999cc models and should be checked against the owner’s manual.
- Made by KOONDHEEND rather than Generac.
Best for: Owners of listed Generac Guardian 16–26 kW, 999cc standby generators who want filters, two spark plugs, and a funnel in one kit.
Not ideal for: Owners of 760–990 cc engines, unlisted generator models, or buyers who prefer a kit from Generac itself or need oil included.
- Model number:6485
- Compatible generator output:16–26 kW
- Compatible engine:999cc
- Compatible models:Generac 7034, 7035, 7043, 7141, 7173, 7210, 7291, and more
- Included components:1 × 070185E oil filter, 1 × 0J8478S air filter, 2 × RC12YC spark plugs, oil funnel
- Recommended maintenance interval:Every 200 hours or 2 years
- Dimensions:6 × 5 × 10 inches
- Weight:1.37 pounds
- Warranty:1-year replacement guarantee
Our verdict“Choose this as a bundled service option for a confirmed compatible 999cc Guardian, but verify its part numbers before ordering.”
Generac 6806 Maintenance Kit for 7 kW PowerPact Standby Generators
The Generac 6806 serves a different buyer from the larger-engine kits here: it is made for the 7 kW PowerPact with a 420 cc engine. Its air filter, spark plug, funnel, chamois, instructions, and reminder sticker make it more than a bare replacement-parts set. The documentation and reminder help owners keep a routine, while the 6484 and KOONDHEEND 6485 kits add oil filters and two spark plugs for their larger compatible engines. That difference matters: this kit should not be treated as a general-purpose Generac service bundle. Its listed interval is every 2,000 hours or two years, subject to the owner’s manual, so I’d confirm the schedule for the exact PowerPact model. The supplied dimensions are listed as 1 × 1 × 1 inches and may not reflect the actual kit size.
Pros:- Designed specifically for the 7 kW PowerPact with a 420 cc engine.
- Includes an air filter and spark plug for routine maintenance.
- Adds an oil funnel, chamois, instructions, and reminder sticker.
- Comes from Generac, unlike the KOONDHEEND 6485.
Cons:- Fit is limited to the specified PowerPact generator and engine.
- Does not list an oil filter among the included items.
- The listed 1 × 1 × 1 inch dimensions may not represent the actual kit.
Best for: Owners of a Generac 7 kW PowerPact standby generator with a 420 cc engine who want routine replacement parts plus service instructions and a reminder sticker.
Not ideal for: Owners of 12–26 kW standby generators or anyone needing an oil filter and multiple spark plugs in the same kit.
- Model number:6806
- Compatible generator:Generac 7 kW PowerPact standby generator
- Engine:420 cc
- Included items:Air filter, oil funnel, spark plug, chamois, maintenance reminder sticker, instruction manual
- Recommended maintenance interval:Every 2,000 hours or 2 years; refer to the owner’s manual
- Dimensions:1 × 1 × 1 inches
- Weight:2 pounds
- Manufacturer:Generac
Our verdict“Buy the 6806 for a confirmed 7 kW PowerPact if its model-specific parts and included service aids match your maintenance plan.”
6485 Maintenance Kit for Generac 16–26 kW Air-Cooled Generators
This RARAYC 6485 is the most focused option in the group: it supplies air and oil filters for compatible Generac 16–26 kW air-cooled generators with 999 cc engines made from 2013 onward. That makes it a narrower replacement-parts choice than the KOONDHEEND 6485, which adds two spark plugs and an oil funnel. I’d favor this kit when those filters are the parts needed and the other service items are already on hand; the smaller bundle avoids paying attention to items outside that task. The listed replacement part numbers also help buyers compare fit with their existing components. Its limits are clear: it does not list spark plugs, a funnel, or oil, and the specified year and engine fit must match. Dusty operating conditions may call for service more often than the stated interval.
Pros:- Includes air and oil filters for routine generator service.
- Lists several replacement part numbers for fit cross-checking.
- Specified for Generac 16–26 kW air-cooled generators with 999 cc engines from 2013 or later.
- Direct replacement installation is stated not to require additional tools.
Cons:- Does not list spark plugs, an oil funnel, or other service accessories.
- Compatibility is limited by engine size and manufacturing year.
- Dusty conditions may require more frequent maintenance than every 200 hours or two years.
Best for: Owners of 2013-or-later Generac 16–26 kW air-cooled generators with 999 cc engines who need replacement air and oil filters and already have other service supplies.
Not ideal for: Buyers wanting a fuller scheduled-maintenance bundle with spark plugs, a funnel, or service accessories, or owners of older or different-engine generators.
- Model number:6485
- Compatibility:Generac 16–26 kW air-cooled standby generators with 999 cc engines, 2013 or later
- Replacement part numbers:0062440, 0062500, 0062580, 0062620, 0062680, 0062770, 0062581
- Included items:Air filter and oil filter
- Recommended maintenance interval:Every 200 hours or 2 years
- Manufacturer:RARAYC
- Dimensions:8.46 × 4.52 × 6.1 inches
- Weight:1.21 pounds
Our verdict“Choose this filter-focused kit when your 2013-or-later 999 cc generator needs air and oil filters, not a complete service bundle.”
Generac 5W-20 Maintenance Kit for 20–26 kW 999cc Generators
I’d choose this kit when having the specified oil on hand matters as much as replacing the service parts. It bundles an air filter, oil filter, two spark plugs, and two quarts of 5W-20 full synthetic oil, unlike the Generac 6485 Scheduled Maintenance Kit for 20–26 kW Standby Generators, which leaves engine oil for the buyer to source separately. That makes this a more consolidated purchase, but the oil grade and engine fit must match the generator’s requirements before ordering. Its coverage is specifically for Generac 20–26 kW models with a 999cc G-Force V-Twin, so I would not treat the wattage range alone as proof of compatibility. The kit also supplies just one of each filter, limiting its usefulness for stocking parts or servicing multiple units.
Pros:- Includes an air filter, oil filter, and two spark plugs for routine service.
- Supplies two one-quart bottles of 5W-20 full synthetic oil.
- Specifically identified for compatible 20–26 kW Generac 999cc G-Force V-Twin generators.
Cons:- Compatibility is limited to the specified Generac engine range.
- Includes only one air filter and one oil filter.
- The included 5W-20 oil may not suit generators requiring another grade.
Best for: Owners of a compatible Generac 20–26 kW, 999cc G-Force V-Twin standby generator who want filters, plugs, and specified synthetic oil together.
Not ideal for: Owners of other engine sizes or brands, and buyers whose manual calls for a different oil grade; the fit and included oil are specific.
- Brand:Generac
- Compatible generators:20–26 kW, 999cc
- Engine:Generac G-Force 999cc V-Twin
- Included components:1 air filter, 1 oil filter, 2 spark plugs
- Included oil:Two one-quart bottles of 5W-20 full synthetic oil
- Model:6485 + A0001412874 x 2
- Item weight:5.2 pounds
Our verdict“Choose this kit if your compatible 999cc Generac calls for 5W-20 and you want oil included alongside routine service parts.”
Generac 6482 Maintenance Kit for 8kW-10kW Standby Generators
The Generac 6482 is a practical choice for owners of 8–10 kW standby generators with 410, 459, or 460 cc engines who want more than filters and plugs in the box. Its funnel, wrench, chamois, reminder sticker, and instructions add useful support for at-home scheduled maintenance. That gives it a more tool-oriented role than the Generac 6485 kit for 20–26 kW units, which includes synthetic oil but targets a much larger engine family. The tradeoff is that oil is not included, so the kit does not cover every purchase needed for an oil change. Fit is also narrow: buyers should confirm engine displacement and generator range rather than assuming this works across Generac standby models. For a correctly matched unit, the instructions and service accessories make routine work more approachable.
Pros:- Includes an air filter, oil filter, and spark plugs for scheduled maintenance.
- Adds a funnel, wrench, chamois, and reminder sticker.
- Instructions support owners doing routine service at home.
- Designed for the specified 8–10 kW Generac engine range.
Cons:- Engine oil must be purchased separately.
- Compatibility is limited to 410, 459, or 460 cc engines in the stated generator range.
Best for: DIY owners of Generac 8–10 kW air-cooled standby generators with 410, 459, or 460 cc engines who want service accessories and instructions included.
Not ideal for: Owners of other output or engine-size ranges, or buyers seeking a kit that includes engine oil.
- Manufacturer:Generac Power Systems Inc
- Model number:6482
- Compatible output:8–10 kW
- Compatible engine sizes:410, 459, or 460 cc
- Included components:Air filter, oil filter, spark plugs, funnel, wrench, chamois, reminder sticker, and instructions
- Oil:Not included
- Product dimensions:8 x 8 x 4 inches
- Item weight:16 ounces
Our verdict“Pick the 6482 if your 8–10 kW Generac matches the listed engine sizes and you value included tools and service guidance over bundled oil.”
6485 Maintenance Kit for Generac 16KW-26KW 999cc Air Cooled Generator
This 6485 kit stands out for its stated coverage across Generac 16–26 kW, 999cc air-cooled generators from 2013 onward, including replacement references for several OEM part numbers. It includes the core service items—oil filter, air filter, and two RC12YC spark plugs—without the added accessories or oil found in some more complete kits. Compared with the Generac 5W-20 Maintenance Kit for 20–26 kW 999cc Generators, this option starts at a lower stated generator output but does not include engine oil. That makes it a parts-focused choice rather than a ready-to-go oil-change bundle. Buyers still need to verify model year and engine size; the broad model list does not extend fit to other engine families. One filter of each type also limits bulk servicing.
Pros:- Includes an oil filter, air filter, and two RC12YC spark plugs.
- Lists compatibility with Generac 16–26 kW 999cc air-cooled generators from 2013 onward.
- Replaces multiple OEM part numbers, simplifying part identification.
Cons:- Engine oil is not included.
- Fit is limited to the specified engine size, generator range, and model years.
- Only one oil filter and one air filter are supplied.
Best for: Owners of 2013-or-newer Generac 16–26 kW air-cooled generators with 999cc engines who need the core filters and plugs across a range of listed models.
Not ideal for: Owners of pre-2013 units, non-999cc engines, or buyers who want oil and service accessories included.
- Compatibility:Generac 16–26 kW air-cooled generators, 999cc, model years 2013 onward
- Included components:1 oil filter, 1 air filter, 2 RC12YC spark plugs
- Oil filter part:070185E
- Air filter part:0J8478S
- Replaces OEM numbers:070185ES, 070185E, 070185B, 070185D, 070185F, 0J8478S/0J8478
- Spark plugs:RC12YC
- Thread size:M16 x 1.5
- Item weight:0.62 kg
Our verdict“Choose this parts-focused 6485 when your 2013-or-newer 999cc Generac falls within its stated range and you will source oil separately.”
Generac 5655 Maintenance Kit for 1.6L Liquid-Cooled Standby Generators
I’d separate this kit from the air-cooled options because it is built for a specific class of equipment: Generac 1.6L liquid-cooled standby generators. Along with air and oil filters, it provides four spark plugs, a plug wrench, funnel, chamois, and reminder sticker. That parts-and-tools mix is more extensive than the Generac 6482 kit for smaller air-cooled units, while remaining focused on a different engine system rather than broad cross-compatibility. The main purchasing gap is substantial: neither engine oil nor coolant is included, so owners must obtain those fluids separately and follow the generator’s service guidance. The listed 200-hour or two-year interval offers a planning reference, but dusty conditions can call for more frequent maintenance. Verify the 1.6L liquid-cooled fit before ordering.
Pros:- Includes an air filter, oil filter, and four spark plugs.
- Provides a spark plug wrench, oil funnel, and chamois for service tasks.
- Designed specifically for Generac 1.6L liquid-cooled standby generators.
- Reminder sticker helps track the stated maintenance interval.
Cons:- Oil and coolant must be purchased separately.
- Compatibility is limited to the specified 1.6L liquid-cooled engine.
- Dusty operating conditions may require more frequent service than the stated interval.
Best for: Owners of compatible Generac 1.6L liquid-cooled standby generators who want filters, four plugs, and basic service tools together.
Not ideal for: Owners of air-cooled Generac units or buyers expecting oil and coolant to be part of the maintenance kit.
- Compatible engine:Generac 1.6L liquid-cooled
- Maintenance interval:Every 200 hours or 2 years
- Included components:Air filter, oil filter, 4 spark plugs, spark plug wrench, oil funnel, chamois, reminder sticker
- Oil:Not included
- Coolant:Not included
- Item weight:2 pounds
Our verdict“Buy the 5655 for a compatible 1.6L liquid-cooled Generac when you want plugs and service tools included and can source fluids separately.”
Generac 6485 Scheduled Maintenance Kit for 20–26 kW Standby Generators with 999cc Engine
This OEM 6485 is the strongest fit here for owners whose 20–26 kW, 999cc V-Twin generator is a Generac, Honeywell by Generac, or Centurion by Generac, provided it was built in 2013 or later. It includes an air filter, foam pre-cleaner, oil filter, two pre-gapped spark plugs, angled funnel, cloth, reminder sticker, and instructions. Compared with the Generac 5W-20 Maintenance Kit for 20–26 kW 999cc Generators, this one lists broader compatible brands and service accessories, but leaves oil out; its listed recommendation is SAE 5W-30 full synthetic. The brand and year limits still matter, and the buyer needs to supply standard hand tools. I’d pick it for a documented fit and guided routine service, not as a universal 999cc kit.
Pros:- Includes an air filter, foam pre-cleaner, oil filter, and two pre-gapped spark plugs.
- Lists compatibility with three Generac-related standby generator brands.
- Adds an angled funnel, microfiber cloth, reminder sticker, and instruction manual.
- Genuine OEM parts and instructions support scheduled DIY maintenance.
Cons:- Engine oil must be purchased separately.
- Compatibility is limited to specified 999cc V-Twin models from 2013 or later.
- Standard hand tools are still required.
Best for: Owners of 2013-or-newer 20–26 kW 999cc V-Twin standby generators from Generac, Honeywell by Generac, or Centurion by Generac who want OEM parts and service guidance.
Not ideal for: Owners of other engine sizes, earlier build years, or buyers who want engine oil included in the kit.
- Compatible generator output:20, 22, 24, and 26 kW
- Compatible engine:999cc V-Twin
- Compatible build year:2013 or later
- Compatible brands:Generac, Honeywell by Generac, and Centurion by Generac
- Included parts:Air filter, foam air pre-cleaner, spin-on oil filter, and two pre-gapped spark plugs
- Included accessories:Angled oil funnel, microfiber cloth, reminder sticker, and instruction manual
- Recommended service interval:Every 200 hours or 2 years, whichever comes first
- Recommended engine oil:SAE 5W-30 full synthetic; not included
- Tools required:Standard hand tools
Our verdict“Choose this OEM 6485 if your generator matches the listed brand, engine, and year range and you prefer included guidance over bundled oil.”
Kohler GM90366 Generator Maintenance Kit
I’d put this kit on the shortlist for owners of the specifically listed Kohler 12RESVL-100LC12 who want several routine service items in one package. It includes two quarts of genuine Kohler synthetic oil, an air filter, an oil filter, and two spark plugs, so it covers more of a basic service than the Generac 6484, which supplies filters and plugs but leaves oil to the buyer. That convenience comes with a narrow fit: the listed compatibility is limited to one generator model, so the part match needs checking before purchase. Compared with Generac’s 0J93230SSM, this kit is identified by a particular Kohler generator rather than a broad output and engine-size range. I’d skip it if your Kohler model differs or if you’re seeking a kit for a Generac unit.
Pros:- Includes genuine Kohler engine parts
- Supplies two quarts of synthetic oil alongside the filters
- Includes two spark plugs for routine service
- Combines several common maintenance items in one kit
Cons:- Compatibility is specified for only the 12RESVL-100LC12
- The supplied oil quantity may not cover every service requirement
Best for: Owners of a Kohler 12RESVL-100LC12 who want filters, spark plugs, and synthetic oil together for routine upkeep
Not ideal for: Owners of other Kohler models or any Generac generator, since the stated compatibility is specific to the 12RESVL-100LC12
- Brand:Kohler
- Model:GM90366-SKP1-QS
- Compatible generator:12RESVL-100LC12
- Included items:1 air filter, 1 oil filter, 2 spark plugs, 2 quarts of synthetic oil
- Dimensions:10 x 13 x 9 inches
- Weight:6.24 pounds
Our verdict“Choose this kit if you own the specified Kohler 12RESVL-100LC12 and want synthetic oil included with common service parts.”
Generac 0J93230SSM Maintenance Kit for 20–22 kW 999cc Generators
This OEM kit is a focused choice for owners of compatible 20–22 kW Generac generators with 999cc engines that call for part 0J93230SSM. Its stated synthetic 5W-20 oil makes it a more direct fit for that service requirement than the Generac 6484, which covers a smaller 12–18 kW range and specifies 5W-30 oil sold separately. The tradeoff is that the product details do not enumerate the included filters or other service components, so I wouldn’t assume it contains the same parts as broader kits in this roundup. Unlike the Kohler GM90366, which names one compatible generator, this kit identifies its fit by output, displacement, and part number. Match all three against your generator’s requirements before buying.
Pros:- Genuine OEM Generac part
- Specifies compatibility by generator output and engine displacement
- Includes synthetic 5W-20 oil
- Intended for routine maintenance and tune-ups
Cons:- Fits only specific Generac models requiring part number 0J93230SSM
- The supplied product details do not identify the individual kit components
- Not suited to owners who need a kit for a different engine size or output class
Best for: Owners of compatible 20–22 kW Generac standby generators with 999cc engines that require part number 0J93230SSM
Not ideal for: Owners of generators outside the stated output and engine range, or buyers who need a clearly itemized list of filters and tune-up parts
- Brand:Generac
- Model and manufacturer part number:0J93230SSM
- Compatible generator output:20–22 kW
- Compatible engine displacement:999 cc
- Oil type:Synthetic 5W-20
- Engine type:4-stroke
- Item weight:2.8 pounds
Our verdict“Pick this only when your 20–22 kW, 999cc Generac requires 0J93230SSM and its listed oil type matches your service needs.”
Generac 6484 Maintenance Kit for 12–18 kW Standby Generators
I rank this as the most flexible fit in this group for owners of 2013-and-later, 12–18 kW air-cooled standby generators with compatible 760cc–990cc engines. Its compatibility extends to certain Honeywell and Centurion models as well as Generac, while the Generac 0J93230SSM targets a narrower 20–22 kW, 999cc range. The kit includes a pre-cleaner, air and oil filters, two pre-gapped spark plugs, and practical service extras such as an oil funnel and instructions. The main compromise is clear: oil is not included, so buyers need to source the recommended 5W-30 full synthetic separately. I’d favor this over the Kohler GM90366 for a compatible Generac-family standby unit, but not for a portable generator or an engine outside the listed range.
Pros:- Fits specified Generac models and compatible Honeywell and Centurion generators
- Includes a pre-cleaner, air filter, and oil filter
- Supplies two factory pre-gapped spark plugs
- Adds an oil funnel, chamois, instructions, and a maintenance reminder sticker
Cons:- Recommended 5W-30 full synthetic oil is sold separately
- Compatibility depends on model year and engine displacement
- Not designed for portable generators
Best for: Owners of compatible 2013-or-newer Generac, Honeywell, or Centurion 12–18 kW air-cooled standby generators with 760cc–990cc engines
Not ideal for: Portable-generator owners, buyers whose engine falls outside the listed range, or anyone who wants oil bundled with the service parts
- Compatible generators:12–18 kW air-cooled standby generators
- Engine displacement:760cc–990cc
- Compatibility:2013 and later Generac models; compatible Honeywell and Centurion models
- Included parts:Pre-cleaner, air filter (0J8478), oil filter (070185E), two spark plugs (0E7585A)
- Included accessories:Oil funnel, chamois, instruction manual, maintenance reminder sticker
- Recommended service interval:Every 200 operating hours or 2 years
- Recommended oil:5W-30 full synthetic; sold separately
- Fuel type and use:Gasoline; residential
Our verdict“Choose the 6484 for a compatible 12–18 kW standby unit when you value broad fit and service accessories more than bundled oil.”
Generac 5656 Maintenance Kit for 2.4L Liquid-Cooled Standby Generators
Among these five picks, the 5656 is the specialist for 2.4L liquid-cooled Generac units, covering specified 25 kW low-speed and 45 kW 3600 RPM generators. Its four spark plugs and dedicated spark plug wrench make it a different proposition from the 6484, which is aimed at smaller air-cooled standby units and includes two plugs. The kit also supplies air and oil filters, an oil funnel, a chamois, and a reminder sticker, giving owners several useful service pieces in one package. It does not include oil or coolant, so it is not a complete fluid-and-parts service bundle. I’d avoid treating it as a general Generac kit: its liquid-cooled engine fit is quite distinct from the 530cc OHVI models served by the 5663.
Pros:- Designed for specified 2.4L liquid-cooled Generac generators
- Includes four spark plugs and a spark plug wrench
- Provides both air and oil filters
- Includes an oil funnel, chamois, and maintenance reminder sticker
Cons:- Oil and coolant must be purchased separately
- Compatibility is limited to specified 2.4L liquid-cooled generators
- The product details do not list an instruction manual
Best for: Owners of compatible 2.4L liquid-cooled Generac standby generators in the specified 25 kW low-speed or 45 kW 3600 RPM classes
Not ideal for: Owners of air-cooled, portable, or other liquid-cooled generators outside the listed 2.4L compatibility
- Brand and model:Generac 5656
- Engine compatibility:2.4L liquid-cooled generators
- Generator compatibility:25 kW low-speed and 45 kW 3600 RPM generators
- Included components:Air filter, oil filter, 4 spark plugs, spark plug wrench, oil funnel, chamois, reminder sticker
- Oil and coolant:Not included
- Recommended maintenance interval:Every 200 operating hours or 2 years
Our verdict“Choose the 5656 if your generator is a compatible 2.4L liquid-cooled model and you need its filters, four plugs, and service tools.”
Generac 5663 Maintenance Kit for 530cc HSB Generators
The 5663 has a narrow but useful job: supplying routine service parts for Generac HSB models with 530cc OHVI engines manufactured from 2008 to 2012. It includes an air filter, oil filter, one spark plug, and several service helpers—a funnel, chamois, instructions, and a reminder sticker. That makes it more convenient than the 0J93230SSM listing for buyers who want the included components spelled out, although the latter targets much larger 999cc generators and specifies synthetic oil. The 5663’s main limitation is age- and engine-specific compatibility; it is not a general-purpose kit for newer Generac units. The product data also gives conflicting descriptions of the engine’s cooling type, so I’d verify the generator’s model and engine requirements rather than rely on that detail.
Pros:- Designed for the specified 530cc OHVI Generac HSB engines
- Includes air and oil filters plus a spark plug
- Provides an oil funnel, chamois, and instruction manual
- Maintenance reminder sticker can help track the next service
Cons:- Compatibility is limited to specified 2008–2012 530cc OHVI HSB models
- Oil is not listed among the included components
- Product details conflict about the engine cooling type
Best for: Owners of 2008–2012 Generac HSB standby generators with 530cc OHVI engines who want listed filters, a spark plug, and service accessories
Not ideal for: Owners of newer Generac models, generators with a different engine displacement, or buyers who need oil included
- Brand and model:Generac 5663
- Compatibility:Generac HSB models with 530cc OHVI engines manufactured from 2008 to 2012
- Included components:Air filter, oil filter, spark plug, oil funnel, chamois, instruction manual, maintenance reminder sticker
- Item weight:0.81 kg
- Engine displacement:530cc
- Engine type:OHVI
Our verdict“Pick the 5663 for a matching 2008–2012 530cc OHVI HSB generator, but confirm the model before ordering.”
How We Picked
I organized these generator maintenance kits by the buyer’s first practical question: does the kit match the generator’s brand, model family, engine type, and service requirements? I then compared how clearly each listing identifies its compatible power range or engine displacement, since a precise fit is more useful than a broad claim based on wattage alone. The lineup includes air-cooled and liquid-cooled standby generators, smaller PowerPact and 530cc units, and one Kohler kit, so compatibility and intended use carry more weight than brand recognition by itself.
The order favors options with a clearly stated generator range and a distinct role for a common ownership need; it does not imply that one kit fits every generator or that similar part numbers are interchangeable. Where multiple entries share a part number or overlapping application, I treat them as alternatives that need a model-number check, not as automatically equivalent products. Because the supplied product information does not establish included-part lists, service intervals, or verified cross-compatibility, I avoid claims about those details and recommend checking the generator manual and the kit’s current application listing before purchase.
Factors to Consider When Choosing Generator Maintenance Kits
Picking a kit is less about choosing the broadest package and more about matching the service parts to the generator you own. I would confirm the generator’s model number, engine family, and maintenance schedule before comparing kit names or part numbers.
Match the Engine and Generator Model, Not Just the Wattage
Two generators with similar output can use different filters or service parts because their engines and model generations differ. Start with the model and serial information on the generator’s identification label, then compare it with the kit’s application listing. Treat wattage as a useful first clue, not proof of fit. This matters across this roundup: 6484 and 6485 listings refer to different stated ranges, while the liquid-cooled kits are specified by engine displacement. If a listing and your manual disagree, pause and confirm compatibility with the manufacturer or an authorized parts source before ordering.
Separate Air-Cooled and Liquid-Cooled Service Needs
Air-cooled standby generators and liquid-cooled units do not share one universal maintenance package. Engine layout affects which service components are required, so the Generac 5655 and 5656 should not be treated as substitutes for the air-cooled 6484 or 6485 families. Check the owner’s manual for the engine type and the parts called for at the service interval you are completing. A common mistake is to buy a kit based on brand and generator size while overlooking the cooling system. If your generator is liquid-cooled, verify both the kit’s stated displacement and the model application.
Read the Parts List Against Your Service Schedule
A kit name does not tell you exactly which maintenance items are inside or whether it covers the task due now. Compare the listed contents with your manual’s scheduled service requirements before assuming the package is complete. Some owners may need only routine consumables, while a generator due for a more extensive service could call for additional parts or fluids. This is especially relevant when choosing among multiple kits aimed at larger 999cc units. Check whether the kit addresses your current interval, and plan for any items your manual lists separately.
Treat Similar Part Numbers and Listings as Separate Until Verified
This roundup includes repeated or closely related 6484 and 6485 listings, plus several kits aimed at 20–26 kW or 999cc generators. Similar titles can describe different applications, packaging, or seller listings, so part-number similarity alone is not enough. Confirm the exact generator model and the kit’s stated fit before choosing between listings. When two options appear to overlap, compare their full application details and included parts rather than assuming one is a newer or more complete version. This extra check can prevent a kit from arriving with components that do not match your engine.
Choose Brand-Specific Parts When Fit and Support Matter
The lineup is weighted toward Generac, with the Kohler GM90366 as the sole Kohler-specific option. A kit from the generator’s own brand may make application matching easier, but the brand name alone still does not prove compatibility with every model. Owners of Kohler equipment should verify the exact generator application instead of choosing a Generac kit based on similar output. For nonstandard or older installations, use the manual and manufacturer parts information as the authority. A less familiar listing can still be suitable, but its fit and part contents need clearer confirmation.
Balance Convenience Against the Cost of Missing Parts
A bundled kit can reduce the effort of sourcing routine service components one at a time, but only if it contains what your next service requires. Before choosing a package, list the parts your manual calls for and compare that list with the kit contents. Buying a kit that omits a needed item can mean a second order and a delay; buying parts you do not need adds little value. Owners who handle regular maintenance may prefer a clearly matched kit, while occasional users may want to confirm the service interval before stocking supplies. For critical backup power, schedule maintenance around the generator manual rather than waiting for a kit purchase to dictate timing.
Frequently Asked Questions
Can I choose a maintenance kit based only on my generator’s kilowatt rating?
No. Output rating is only one compatibility clue, and generators in the same range may have different engines, model generations, or cooling systems. Check the model number and engine details on the generator, then confirm that the kit listing names that application. The 6484 and 6485 entries here show why the distinction matters: their stated ranges differ, and several listings specify 999cc engines. If the kit information does not clearly match your generator, verify fit before ordering.
Are the different Generac 6484 or 6485 listings interchangeable?
Do not assume so from the shared part number or similar title. The listings describe different ranges and, in some cases, specify engine details or scheduled maintenance use differently. Compare the full model application and included-part list with your generator manual. If two seller listings appear to cover the same unit, use the manufacturer’s compatibility information to resolve the difference. The safest choice is the listing that explicitly matches your generator model and engine.
How do I know whether I need an air-cooled or liquid-cooled kit?
Check your generator’s owner’s manual or identification information for the engine and cooling system. Air-cooled kits in this roundup include families such as the 6484, 6485, 6482, and 5663, while the 5655 and 5656 are identified for liquid-cooled engines with different displacements. These categories are not interchangeable simply because the generator output seems similar. If the documentation is unclear, confirm the engine type using the exact model number before ordering.
Do these kits include everything needed for a complete scheduled service?
That depends on the specific kit and the maintenance interval; the product name alone cannot establish what is included. Compare the kit’s parts list with the service items in your generator manual, including any items the manual says to replace at the interval you are completing. Some service tasks may require parts or supplies sold separately. Check the contents before purchase, particularly for larger 999cc models with multiple kit listings. Follow the manual’s instructions for the actual maintenance work.
Which kit should I choose if I own a Kohler generator rather than a Generac?
The Kohler GM90366 is the lineup’s brand-specific starting point, but you still need to confirm that it matches your exact Kohler generator model. Do not substitute a Generac kit based only on similar power output or a perceived overlap in parts. Check the Kohler manual and the kit’s stated application, then compare the listed contents with your scheduled service needs. If the model match is not explicit, ask a Kohler parts source to confirm before ordering.
Conclusion
Best overall: I’d start with the Generac 6484 for a 12–18 kW standby generator when its application matches your model. Best value: the Generac 5663 is a focused option for compatible 530cc HSB owners who do not need a larger-engine kit. Best premium fit: for a compatible 20–26 kW 999cc unit, compare the Generac 5W-20, 6485, and 0J93230SSM listings against your manual rather than paying for features you cannot verify. Best for beginners: the clearest match is the kit whose listing states your exact generator family and engine, making compatibility checks simpler than choosing by wattage alone. Best for specific needs: choose the 5655 or 5656 for the stated liquid-cooled engine application, the 6806 for a compatible 7 kW PowerPact, or the Kohler GM90366 for a matching Kohler model. Before ordering any of them, confirm the model and parts list; fit matters more than a familiar kit number.
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