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No one really enjoys degreasing their car engine – or at least we’ve never found anyone who will admit it anyway. But if you really want to help your engine to perform at it’s best over the long-term then it is a good idea to get under the hood and get busy with a quality engine degreaser.
A clean engine will run better with less chance of gunk and dirty grease clogging moving parts or air intakes. It’s also easier to maintain a clean engine, allowing you to spot issues such as oil leaks early and fix them before they become a serious problem.
Whilst there are numerous degreaser products on the market today, all boasting that they will leave your engine sparkling, choosing the right one can be tough. That’s why we’ve put together our list of the best engine degreasers, as well as a useful buying guide & FAQ, to help you make the right choice.
The Best Engine Degreaser
The Crystal in the name refers to the fact that this product is Crystal clear both in appearance and odor. This makes it stand out from Simple Greens other line of cleaning products, many of which are, surprise surprise, green in color.
This means that this product lends itself very well to degreasing an engine where you really don’t want a range of containments – such as color dyes – to be hanging around your engine. Instead, this product is non-toxic, biodegradable, non-hazardous, non-corrosive and non-flammable.
It is however a very effective degreaser and cleaning product, which will really get to work on your engine. It’s highly concentrated too, so you can dilute it in your spray bottle before application. That helps the product stretch a little further which given the pretty high price tag of a shade under 30 bucks is a very welcome feature.
Fragrance & Color Free
Non-Toxic and Biodegradable
- BrandSimple Green
- Weight9 lbs
Is it a bird? Is it a plane? No, it’s super degreaser! Look, if you’ve been on Car Bible for a while you know generally we really question any product that comes at us with some bold claim right there in the product name. However when that product also comes from a highly reputable manufacturer like Meguiar’s, then we sit up and take notice.
This product is all about the power degreasing action. It is a unique formulation specifically designed to tackle even the toughest grease, working hard to break it down so you simply rinse it away with a good stream of clean water.
It’s also specially formulated to be residue free, meaning that after rinsing you won’t be left with any streaks or white marks left behind – an important feature if you really want a sparkling engine you’ll be proud to show off.
It does have a strange herbal fragrance. Some people won’t like it, some people will and many won’t even notice it, but as a somewhat unique feature it is at least worth mentioning.
- Weight3.31 lbs
Despite it’s mildly aggressive name, this product from Oil Eater is actually a remarkably gentle product. It is – deep breath required here – non-toxic, non-corrosive, non-hazardous and even USDA approved for non-food surfaces. It is also acid free and contains no abrasive or petroleum solvents.
That is an impressive list of things it is free from and kind to, but don’t let that detract from it’s main purpose however. This product is made for degreasing and it does that very well, tackling and dissolving all manner of greases and oils.
It’s also safe for use in a wide range of non-car related applications. It can be relied on to safely clean any grease and oil stains from all sorts of materials, everything from carpets to asphalt. That fact helps to make this an extremely versatile product. It’s highly concentrated so you can dilute it to suit whatever task you require, and with a price tag of under 20 bucks for a gallon bottle it is very good value too.
Acid Free, Non-Abrasive
Wide Range of Applications
- BrandOil Eater
- Weight8.5 lbs
First thing we want to have on record is that we love the name! The second thing we want to highlight here is that this product really does live up to its name, and it is capable of Kutting through all sorts of Krud.
Not only can it Kut the Krud effectively however, it can cut it on a wide range of surfaces. What we have here is a product a little unlike most of the cleaners on this list. By that we mean this is not really a specialist product that has been designed for the automotive world. Instead this is a cleaner with an exceptionally wide range of applications – one of which is degreasing engines. Not only can it clean grease & oil though, it also works to clean up glue, markers and crayon, paint and tape residue to name just a few.
It’s also a very mild product, being water based and biodegradable whilst containing no petroleum solvents, bleach or ammonia. The fact you get a gallon for a little over 10 bucks is great value – but some people may prefer a more specialized, dedicated degreasing product.
Very Wide Range of Applications
Removes a Number of Containments
Biodegradable & Water Based
- BrandKrud Kutter
- Weight9 lbs
It’s not Puppy Power we’re dealing with here, but Purple Power. And unlike Scooby’s deeply irritating nephew, this product actually has the power to back up its claims.
This product is another that is not a dedicated automobile cleaning product. Instead, it is a powerful degreasing (and cleaning) product with a range of applications, one of which is to spray it onto your engine and let it work it’s magic. It’s non-abrasive, phosphate free and biodegradable, however we suspect it may not be as gentle as some other products on this list.
For example, hidden in the instructions it does state not to use it on Plastics or Aluminum. That means you need to be very careful when spraying it around your car.
It is very cheap on the other hand, and you can expect change from 10 bucks, making this easily one of the cheapest on the list. So in summery it’s cheap, it cleans very effectively (and very quickly) just be sure to treat this product with extra care.
Very Low Price
- BrandPurple Power
- Weight8.3 lbs
After a few all round cleaning products, we now get back to one designed specifically for use on cars, and it is made by one of our favorite brands The Car Guys.
This degreaser they’ve brought to the market is not just orange in color for the hell of it. No, The Chemical Guys have instead harnessed the natural cleaning power of Citrus to develop this powerful cleaner that is formulated to emulsify dirt, grime and oil stains and spills. Once emulsified, the containments can be easily rinsed away with a spray of clean water.
It has a multipurpose element too, being suitable for use all over the vehicle such as on the undercarriage and even to remove caked on mud and grime from rims and wheels. It even works on other surfaces too so you can tackle oil stains on your garage floor and even bring the sparkle back to your tools.
It’s relatively cheap, with a price tag a shade under 10 Bucks, you should note however that this price buys you only 16 ounces of product – a relatively small amount since many other products on this list are sold by the gallon. It is very highly concentrated however, so you can dilute it which adds a bit more value.
Citrus Based Formula
Emulsifies Dirt & Grease
- BrandChemical Guys
- Weight1.08 lbs
We love it when a product lives up to its name, which is why the Tough Task Degreaser from SuperClean has made it onto our list. It really is suitable for even the toughest tasks, as this is industrial strength degreaser and cleaner. After application it is designed to get to work instantly, and works to dissolve a wide range of materials such grease, grime, oil and even tar.
At the same time however it’s relatively mild, being a water based solution that’s both biodegradable and phosphate free. It’s perhaps not as mild as some of the others on this list so do take care, however for the cleaning power it delivers it is certainly milder than it could be.
Its also extremely concentrated so can be easily diluted (all the way down to 16:1, or so the manufacturers claim anyway) so you can make the 32-ounce bottle go a very long way.
- Weight2.2 lbs
The good thing about choosing a multi-purpose cleaner is that you know it is going to be mild enough to use on a range of surfaces. That is however somewhat understating the abilities of this cleaner and degreaser from Simple Green, which has a phenomenal list of materials it is safe to use on.
Amongst that list we find painted surfaces, aluminum, polished & stainless steel, chrome, plastic and vinyl (amongst many, many others). That means whilst you still need to be careful (as this is a powerful cleaning product) you should be able to spray it all over your engine block without having to worry too much about any product blowback coming into contact with any surface it shouldn’t.
It has a wide range of uses in the home, making it extremely cost effective and the product is non-toxic so you don’t have to worry about the run-off getting onto your lawn when you’re rinsing the car down.
Wide Range of Applications
Safe on a Huge Range of Surfaces
- BrandSimple Green
- Weight9.3 lbs
We finish up with a cleaner from the Chemical Guys that, if nothing else, wins the award for best product name. Whilst the name is funny, it does live up to it, being an extremely concentrated and very strong degreasing product. That means you can happily dilute it down quite a lot and still get a great cleaning effect, meaning this gallon bottle could last quite a long time.
It is formulated to tackle even baked on dirt, grime and oil and has also been designed to rinse away without leaving any residues behind. If you’re looking for a product with a deep clean that leaves a shiny engine behind then this could be the one for you.
It is also safe to use on a range of surfaces across the car such as tires and wheel wells, though it’s main power is definitely in degreasing, so you may want to keep it to one side as a dedicated engine degreaser. It’s also not cheap, costing about 35 bucks per bottle, but the fact you can dilute it does help it go a little further.
Heavy Duty Cleaning Product
- BrandChemical Guys
- Weight9.7 lbs
Best Engine Degreaser Buying Guide & FAQ
As promised, that is our list of what we think are the best degreasing products on the market right now. Whilst any one of them will no doubt do a good job for you, which one is going to do the best? Because as we said up top, degreasing the engine is not particularly fun, so you really want to invest in the product that is going to make the job as simple and straightforward as possible.
That’s why we’ve put together this product buying guide and FAQ to talk through all the features to keep an eye out for, and also answer any questions you may have to help you get the most out of your selected product.
Essential Factors to Consider When Selecting the Best Engine Degreaser
Multi-Surface - Take a look at the number of surfaces the product can be used on. If it’s saying that it can be used (or at least is not harmful to) plastics, painted surfaces, etc then you don’t need to be quite as careful when you’re using the product.
Multi-Purpose - Some products are intended just for the car, some are intended for use around the home and garage too. A multi-purpose product will generally be milder so it can work on a variety of surfaces. It is however better value, as you’re getting the ability to clean a wide range of surfaces with one product.
Smell - A petroleum based cleaner is probably going to smell pretty bad, and you may want to invest in a simple dust mask or something to block the odor. At the other end of the scale, some of these products have added perfume to smell nice. Whether this is at all important will depend on you!
Size - This also goes with price. Frankly, there are some bargains on the list, with many products sold in gallon-sized bottle for relatively low prices. How has that low price been achieved however, and will the cheaper options truly match the cleaning power of the premium brands?
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Types of Engine Degreaser
Broadly speaking there are two types of engine degreaser, and you can find examples of both of them on the list above. They are Petroleum Based degreasers and Water Based degreasers. Both formulas have pros and cons, so do take a quick look at the product type breakdown here – it might help you to decide which product is going to be better for you.
- Petroleum Based - In general, petroleum-based cleaners will usually be cheaper than a water based product. This is because it is naturally a stronger cleaning product, which doesn’t need the high end formulations that are found in water-based versions. They are also very powerful cleaners, but they can be more abrasive than the water based solutions so you need to be careful when applying them and wipe away any run off or splash back that sprays onto painted surfaces, plastics, chrome and aluminum (unless the product specifically states it is safe on these surfaces).
- Water Based - A degreaser with a water base will naturally be that much gentler and milder than petroleum based versions. They can also be just as effective a cleaning agent, though they will often boast a more high tech formulation to tackle grease and oil than the raw muscle power of petroleum based products. They are going to be milder to use on a range of surfaces, meaning that you won’t have to panic quite so much if the product comes into contact with other surfaces on the car – many products are in fact designed to clean them too. They will usually be more environmentally sound too, so you don’t have to worry about run-off damaging your lawn. The downside is they usually carry a higher price tag.
There is a third type as well, which is the foaming engine degreaser. However, the two types we mentioned above, whilst having a few differences are at least similar in how they are applied and used. A foam based cleaner is quite different, and there exist enough of that type that it really does warrant its own guide – which, if you’re very lucky, we’ll make for you one day.
Engine Degreaser FAQ
Have any questions either especially about degreaser products, or the related topics of cleaning your engine? Well, you’re in luck friend, because this is our section all about Frequently Asked Questions when it comes to Engine Degreasers.
Q: What is In Degreaser?
A: There are a quite a range of ingredients in a degreasing product, and each one will have a slightly different mixture. Even where they share ingredients, they will often be in slightly different quantities across the various brands.
Broadly speaking however these products contain some kind of agitator that works to break down the grease, oil and dirt as well as a solution (normally either petroleum or water based) into which the agitating ingredients are suspended.
The cleaning ingredient(s) differ from product to product and are often a closely guarded secret held by each manufacturer. In our list above you can see some products that include an Emulsifying agent to quickly break down grease and oil and make them easy to wash away. We even have a product that uses Citrus as it’s cleaning agent. Each manufacturer may not specify exactly what the cleaning agent is, but broadly speaking they all perform the same function.
Q: What is Engine Detailing?
A: Remember when you were a kid and your Mom told you to clean your room and you just stuffed everything into the closet and played Playstation instead? That is the same as taking your car to an automatic washer. It looks clean, but it’s only really touching the surface.
Remember when she caught you stuffing your dirty laundry and old toys into the closet, and you spent a summer afternoon filling up garbage bags with crap? That is a level of deep and long lasting cleaning equivalent to engine detailing.
Engine detailing is a very deep clean of the engine block that requires time and tools – but it is worth it for the end results. Here is a nice man with a ponytail to explain further.
Q: Is Degreaser Harmful?
A: Yes, if use it as a mixer in a cocktail.
No, if you follow the instructions. Depending on the type of product you’ve gone for, there will be some materials it is safe to come into contact with and some it is not. Read the instructions on the product you buy and everything will be fine.
Q: What Parts to Cover when Cleaning an Engine?
A: Make sure you cover sensitive parts of the engine before you start, such as:
You don’t need anything fancy either – some plastic bags will do, just tape them into place if needs be.
Q: How to Remove Engine Sludge?
A: Engine sludge is a little different from the build up of oil and grease found on the engine surface. It builds up if you haven’t changed the oil in a while. The easiest way to tackle this is to add a chemical sludge remover to the oil and idle the engine for 10 minutes.
Then perform a full flush to remove the old oil (and sludge) and replace with fresh synthetic oil.