Best Parts Cleaner for Parts Washer: 5 Picks by Formula, Flashpoint and Tank Size

Compare the picks

*Denco capacity is listed as 13 oz in the title and table but 15.3 fl oz in the bullet points. Specifications are manufacturer rated, as published on each listing and collected 9 October 2026.

How we scored them

Each product is scored out of 10 on performance, build, value, safety and warranty, using the evaluation criteria explained on our How We Pick page. Performance evaluates cleaning potency and suitability for parts washer tanks. Build reflects formulation stability or tank construction. Value weighs volume and usable life against capabilities. Safety scores recognized environmental certifications, stated flashpoints or electrical protections. Stated manufacturer warranty terms earn warranty points, while listings without a stated warranty receive zero for that criterion.

Scores run from 9.2 to 9.8: each product’s point total is placed on that range, so more points always means a higher score.

What the listings tell you

We analyzed five parts washer and cleaning chemical listings. Three listings represent liquid bulk fluids, one is a 48-pack of aerosol spray cans, and one is a complete 40-gallon steel wash basin station. Concrete warranties were stated on only two listings: Oil Eater provides a 1 year manufacturer warranty, and Eastwood specifies a 1-year limited warranty with a 90-day return policy. The other three listings state no warranty term. Contradictions appeared on multiple listings: Denco lists 13 fluid ounces in its title and spec table but claims 15.3 fluid ounces in its bullet points, while listing a total weight of 14 pounds for 48 cans. Simple Green describes an industrial degreaser for equipment and dip tanks in its text, but its spec table lists carpet and upholstery as specific uses. Only B’laster states an exact flashpoint at 145°F, and only Simple Green notes recognition under the U.S. EPA Safer Choice Program.

Best parts cleaner for parts washer: buying guide

Water-based vs solvent cleaners

Parts cleaners fall into two primary categories: petroleum-based solvents and water-based biodegradable cleaners. Petroleum solvents break down stubborn petroleum grease and heavy oil quickly, leave minimal residue, and dry without water rinsing, making them practical for prepping bare steel before paint or reassembly. Water-based cleaners are concentrated, biodegradable, low-odor formulas that can be diluted for custom strengths, but parts washed in water-based solutions generally need rinsing and drying to prevent flash rusting on bare iron.

Flashpoint and shop safety

Flashpoint indicates the lowest temperature at which a solvent vaporizes into a flammable gas mixture. Ordinary mineral spirits can ignite at lower temperatures, presenting serious hazards around garage sparks and electrical switches. Dedicated parts washer solvents specify elevated flashpoints, such as the 145°F flashpoint listed on the B’laster 5-PWS solvent, to provide safer operation in busy shop environments. Always maintain adequate cross ventilation and keep fire extinguishers accessible.

Parts washer pump compatibility

Electric parts washer pumps are engineered for specific fluid chemistries. Many standard submersible pumps, such as the 120V pump on the Eastwood 40-gallon washer, are intended for water-based cleaners or high-flashpoint petroleum solvents. Using low-flashpoint solvents, gasoline or unapproved thinners can destroy pump impellers, dissolve electrical cord insulation, and create electric shock or fire risks. Always check pump specifications and fluid chemical recommendations before filling a tank.

Aerosol cleaners vs tank fluids

Aerosol spray cans like Denco 1930 deliver high-pressure blasts that displace grime on assembled parts, such as brake calipers and suspension links mounted to a vehicle. However, aerosol cans cannot replace recirculating tank fluids: they produce aerosol overspray, evaporate immediately, and cannot provide continuous soaking or brush-assisted flushing. Dedicated 1-gallon and 5-gallon fluids are designed specifically for immersion and circulating tanks.

Disposal and environmental rules

Spent cleaning fluids collect heavy metals, dissolved motor oil, and grease during use. Even biodegradable cleaners like Simple Green and Oil Eater cannot simply be poured down household drains once contaminated with automotive motor oil or transmission fluid. Store spent solvent and dirty rinse water in sealed drums and take them to a licensed municipal hazardous waste facility for recycling or disposal.

For engine teardowns, an engine stand and a solid work bench with vise provide stable mounting while you clean greasy components.

Frequently Asked Questions

How does parts washer work?

A parts washer circulates cleaning solution over dirty automotive and machinery components to loosen grease, oil and grime. In a powered tank, an electric pump draws cleaning fluid from a basin or reservoir through a filter and delivers it through a flexible spigot or flow-through brush. The fluid washes over parts positioned on an internal work tray, drains back into the tank through a strainer, and recirculates to provide continuous cleaning.

How to use parts washer?

Place greasy components onto the internal parts tray inside the tub. Position the flexible fluid nozzle over the component to flood the dirty surfaces with cleaning fluid. Allow the solution to loosen stubborn grease deposits, then scrub the components with a parts cleaning brush. Let excess fluid drain back into the basin, rinse water-based solutions if required by the chemical maker, turn off the pump, close the lid and unplug the unit when finished.

Can you use diesel in a parts washer?

No. Diesel fuel should never be used inside a parts washer. Diesel is a combustible motor fuel with a low flashpoint that creates serious fire and explosion hazards when pumped or agitated in a shop basin. In addition, diesel produces strong fumes, poses health risks upon skin contact, and can degrade pump seals and rubber hoses. Always use purpose-formulated parts washer solvents with high flashpoints or water-based biodegradable degreasers.

Do I need a parts washer?

A parts washer is worthwhile for anyone who frequently rebuilds engines, cleans automotive calipers, services transmissions or restores greasy machinery. Instead of spraying single-use aerosol cans that produce runoff and fumes, a dedicated parts washer recirculates fluid in a contained basin with a filter. For occasional single-bolt cleaning, aerosol spray cans or a small benchtop dip tank may suffice.

How much are parts washers?

Parts washers range from compact benchtop tubs and portable dip tanks to large freestanding shop basins with electric pumps. Small benchtop units and manual soak containers sit on a workbench, while larger freestanding steel units offer capacities such as 40 gallons with powered flow pumps, flexible spigots and powder-coated steel stands. Operating expenses also depend on whether you choose dilutable concentrated water-based degreasers or 5-gallon buckets of dedicated solvent.

Related: our guide to the best oil drain pan, the cheap oil drain pan, the best mechanic tool cart, our engine and shop equipment hub and our best starter mechanic tool set.