7 Best Leak Down Tester Reviewed in 2023 [Ultimate Guide]

Is your vehicle engine giving you issues? Or it isn't just working right, and you don't know how to find out what's wrong. What you need to check the engine's working condition is a leak down tester.

Usually, people go for a compression tester, but it can only do a general check on the engine. It can't figure out exactly what's wrong with it.

A leak down tester will find out what's wrong and also where the problem is.

Many leak-down testers aren't accurate. Finding the one that’s accurate and compatible with your vehicle’s engine can be a tedious task. 

However, this comprehensive list of the 7 best leak down testers in 2023 for different engines is all you need.

Our 7 Best Leak Down Tester Picks:

Here is our detailed guide on the top leak down testers that you can use to diagnose your vehicle's engine-

1. OTC 5609 Cylinder Leak Down Tester Kit

The OTC company is a branch of the Bosch brand that majorly produces and distributes heavy-duty electronic diagnostic devices. Their equipment gives one of the most accurate diagnoses in the industry.

One of their heavy-duty products is this OTC 5609 cylinder leak down tester kit. It is a time-efficient, reliable tester for diagnosing internal engine issues like bad valves, leaking head gaskets, bad rings, etc. This equipment has a size of 10.25" × 8.75" × 3.8" and weighs only 4 lb. Also, it's cheap.

It has dual 2½" gauges with a pressure calibration from 0PSI to 100PSI and 0kpa to 700kpa. Furthermore, the chrome bezel and tough protecting external boots provide durability and endurance.

This leak down tester has a pressure-regulated manifold that helps adjust and verify pressure at different sections. It works with couplers that are compatible with a flex 24" 14mm hose. Also, it comes with 10mm, 12mm, and 18mm thread adapters for performing many applications.

The OTC 5609 cylinder leak down tester has a well-built blow-molded hard casing with a movable cover where it's kept organized and protected when not in use. The case also has a handle for easy transportation.

However, be informed that this tool can't be used as a compression tester. It's strictly for testing leakages in piston engines that have spark plugs and diesel engines with preheating plugs. Also, it has a detailed instructional chart for directions on how to use it.

Pros

• It comes with different size of adapters for many applications
• Its accuracy is spot-on
• Dual pressure gauges
• Simple to use
• Cheap
• Heavy-duty plastic casing
• Detailed instruction outline for user guide

Cons

• The threaded part of the adapters may be short for some engines

2. Motion Pro 08-0071 2-Stroke Leak Down Tester

If you want to test a two-stroke engine for air leaks, this Motion Pro 08-0071 2-stroke leak down tester is our recommendation. Motion Pro specifically created it for testing air leaks in a 2-stroke engine.

This leak down tester is made in the USA, so rest assured that all its parts are of premium quality. It functions with an air pressure gauge that reads pressure in PSI. Also, it comes with a pump-up bulb.

The fittings and adapter of this leak down tester are compatible with standard single and dual cylinder 2-stroke engines.

Intake adapters with dimensions for 35mm, 41mm, 43mm, or 46mm intake manifolds come packaged with it. With these adapters, the Motion Pro 08-0071 2-stroke leak down tester finds use in a wide range of 2-stroke car and motorcycle engines.

Additionally, it has rubber exhaust port plugs that expand to fit ports of 35mm to 60mm in diameter.

This tester weighs 5.95lb and comes in a handy carry box, with a well-written user manual. This device works well, but it's more expensive than most testers in its category.

Pros

• It works well for 2-stroke engine
• Comes with fittings and adapters for use on engines of different sizes
• Made in the USA
• Lightweight
• Well-written manual

Cons

• Air gauge doesn't start from 0 PSI
• It's a bit pricey

3. Lang Tools CLT-2 100 PSI Cylinder Leakage Tester

Lang Tools is a family-owned tool manufacturing company in Racine, Wisconsin, that has been producing automotive tools since 1932.

They have a large variety of different equipment that solves and diagnoses problems in auto vehicles. Of which, one of them is this CLT-2 100 PSI cylinder leak down tester. This Lang leak down tester features state-of-the-art technology to provide an accurate diagnosis.

It accurately measures the air present in an engine cylinder with its precision regulator.

Furthermore, it uses two 2½" M68 gauges. The first gauge has a scale that reads from 0-100% and a multicolored band that indicates when air leakage is low, moderate, or high. Simultaneously, the second gauge reads pressure from 0-100PSI and 0-7bar to monitor input air-line pressure.

All part of this leakage tester is made from sturdy metal in the USA. However, the gauges are made in China, and they have rubber covers. Note that the gauges are non-calibratable.

This equipment is affordable and does what it's made for efficiently. It comes with a 26" hose that has M14 standard reach and long reach adapters.

Also, it comes with a manual and a carry case with a total weight of 5.75lb. Be informed that this tool is a supplement for a compression tester. Thus, it can't work as a compression tester.

Pros

• Affordable
• Dual easy to read gauges for accuracy
• Carry casing
• Instructional manual
• Heavy-duty

Cons

• The hose and adapters are flimsy

4. LEIMO Cylinder Leak Down Tester

The LEIMO cylinder leak down tester works well to check and diagnose air leaks in any car or truck with a 4-stroke engine. It is a heavy-duty cylinder leak down detector that works effectively and efficiently.

As long as clearance is minimal in your vehicle, this device is sure to give accurate results. It helps find common engine problems like worn piston rings, worn valves, blown head gaskets, and cylinder head cracks, to mention a few. And the best part is it's inexpensive compared to other cylinder leak down testers.

Further, it has a pressure regulator and a dual gauge system consisting of an air leakage gauge and a 2½" pressure gauge. Its air leakage gauge shows the percentage of air leaks present in the engine tested on a scale of 0% to 100%. While its pressure gauge shows the amount of air present on a scale of 0-100PSI. However, this gauge system isn't accurate sometimes.

This leak down tester works with a 480mm hose having a female connector and two male spark plug adapters of 12mm and 14mm diameters. Also with a fixed short M14 x 26mm connector and an M16 x 26mm fixed short connector.

With its adapters and connectors, the LEIMO cylinder leak down tester is versatile for many engines. It has a carrying case for easy and organized carry along to Jobsite.

Plus, there's an instruction manual to guide users on its usage. LEIMO has a 30-day back guarantee when you buy this device if you don't like what you get.

Pros

• Dual gauge system
• Carrying case
• User-manual
• Works well with many 4-stroke engines
• 30-days money-back guarantee
• Cheap

Cons

• It's not always accurate
• It isn't durable

5. ATD Tools 5573A 2-Gauge Cylinder Leakage Tester

Most cheap tools are cheap because of the substandard materials used in producing them.

But, the ADT company doesn't compromise on its product's quality, even though they are inexpensive. If you are on a budget and you need a high-quality, accurate cylinder leakage tester that will last for a while, then this ATD Tools 5573A 2-Gauge cylinder leakage tester is right for you.

It is cheap and offers an accurate diagnosis of air leakage volume and where it's coming from in an engine.

This cylinder leakage tester has an anodized circular body that gives it an attractive appearance. It functions with a 2-gauge design.

One pressure gauge with a dual scale of 0-100PSI & 0-7 bar, and one air leak gauge with a scale of 0-100% underneath a multicolored band for measuring low, moderate, and high air leakage.

ATD recently improved these gauges by making them bigger and more readable. Also, they added a gauge boot to boost their durability. This tester's pressure regulator is easy to use and provides precise monitoring of the input air pressure.

Furthermore, they have an industrial interchangeable quick coupler compatible with standard compression test adapters. However, you'll need to remove the valve core for it to fit some adapters.

When you buy this tester, it comes in a casing containing an M14 short thread adapter on a 26 hose assembly, an M14 long thread solid adapter, a ¼" female, and a ⅛" male reducer adapter. Also, it has a year warranty.

Pros

• Cheap
• Good quality
• Big and easy to read
• It's accurate
• It has a carrying case

Cons

• It may leak

6. ABN Cylinder Leak Detector & Engine Compression Tester Kit

Another air leak down tester designed explicitly for gasoline 4-stroke engines is the ABN cylinder leak detector & engine compression tester. It helps diagnose engine faults such as worn piston rings, blown head gaskets, worn valves, cracked cylinder walls in cars or trucks with minimal clearance, and a 4-stroke engine.

Just like most of the modern leak down testers, this tester comes with a twin gauge manifold for pressure measurements in PSI (0-100) & bar (0-7) and air leakage volume measurement in percentage (0-100%) low, moderate, and high levels.

These gauges are big, easy to read with a 2.9" diameter scale, and have a shockproof rubber enclosing protector. Moreso, it has an easy-to-use air regulator for controlling air intake.

This tester comes in a well-built plastic blow-molded carrying case with dimensions of 14.8" x 3.1" x 10.75". The casing helps store the tester and accessories in an organized manner and for easy transportation.

It comes with 12mm and 14mm spark plugs that fit perfectly into any standard 12mm or 14mm spark plug socket. Also included is a 480mm Flexi hose, M14 x 26mm fixed short connector, and an M16 x 26mm fixed long connector.

Pros

• Works excellent for 4-stroke engines
• Sturdy carrying casing
• Cheap and offers good value for money
• Easy-to-use

Cons

• Air coupler fitting may not fit well for some engines

7. Star (STACLT-2PB) Cylinder Leakage Tester

To round up our list is this (STACLT-2PB) cylinder leakage tester from Star water systems company. This tester accurately measures an engine cylinder's ability to contain air and detect any air leakage.

Its dual gauge system effectively detects faults such as blown head gaskets, bad valves, worn rings, and cracked cylinder walls in an engine cylinder.

The gauge system comprises two 2¼" diameter gauges with different pressure measurements. The first one measures inline pressure in two scales; 0-100PSI and 0-7 bar.

The second one measures the air leaks with a scale that reads from 0% to 100% and a multicolored band that tells if air leakage is high, moderate, or low. These gauges have a rubber covering to protect them.

Also, it has a precision air regulator for controlled air supply. This tester comes with an M14 and M18 adapter fixed on a 26" hose assembly. It weighs 2.455lb and has a carry casing for storage and easy transportation.

Pros

• Solid construction
• Easy-to-use
• Carrying case
• Cheap with great value
• Works well

Cons

• None

Leak Down Tester Buying Guide

The Leak-down tester is an innovative device that detects the efficiency of internal combustion engines. It works by sending compressed air into the cylinder, and the amount of leak is monitored. The less the leak, the better the engine. Here are some factors to consider when you want to get a leak-down tester:

Ease of Use

This is one of the most notable factors of all. Gone are the days when leak down testing is not a thing to do for yourself, or rather, by yourself. You don’t need to visit an automobile mechanic regularly if you are well informed. Engine tests should not be something you perform in a while. You should check the condition of the engine regularly; late detection of problems is usually catastrophic. This is the main reason why you need to get a leak down detector that is very easy to operate.

Versatility

Check if the leak-down tester can work with various types of internal combustion engines and not just one type. There are many testers that work perfectly with petrol engines, but you may need more degree of freedom.

A versatile leak down tester works well with gasoline engines and other types of internal combustion engines. For example, Ford triton engines have a new formula for their engine system. Check if the leak tester can work with that.

You may not mind getting a tester that works in just one engine type. Regardless, getting a versatile one for some extra cash or even the same price won’t be a bad deal in any way.

Digital Charts and Display

Most leak down tester has real-time analog gauges that are meant for close human observation. You may want the comfort of a digital display system. Some leak testers have digital displays that reports actual numbers and values, in real-time. They even come with a hold option that temporarily stores test results.

Digital charts are displayed on the screen, some of which are operated by touch. They may also have extra details like professional pieces of advice and time records of previous tests. It definitely gets better.

Flexibility of Adapters

A lot of vehicles have different engine systems and valves, all depending on manufacturers and models.

Ensure you get a leak down tester that has adapters to work with most vehicle requirements. Most leak-down testing kits come with various attachments, be sure to check out that yours comes with many adapters to serve dynamics purposes.

Also, some adapters have adjustable geometry that makes up for use in different scenarios; you might want to have one of those.

Corrosion Resistance

How well does the leak down test resist corrosive conditions? This is totally dependent on the material used to make the tester or the material it is coated with.

Nickel-plating for surface finishing is a good option that prevents corrosion of devices. Some other materials also serve well; just make sure the leak down tester you purchase is made of a very strong corrosion resistance material, and that will really go a long way.

Weight of Device

The leak down tester does not need to be very heavy; the operation gets harder if it is. This point is not totally technical but still one to consider.

A heavy testing device doesn’t necessarily mean a better one or a stronger one. Most of these devices have their details like the weight in their spec information, be sure to check that before you buy.

Sensitivity Levels and Operation Modes

A few advanced leak-down testers have options of choosing different modes. Each mode has a different sensitivity level of measurement that is calibrated to a certain degree. Having the options of testing with different sensitivities is surely a plus. You have more information, and you test as more conditions. This way, your conclusions are surer.

Fluid Testing and Indication

Few leak-down testers have this function. The fluid indicator is a very unique and precise innovation. It comes with a tube compartment that holds the indicator fluid. This session is the actual part that does the testing.

If the testing fluid changes to yellow after the test, it shows that the engine in question has damages that cause leakage, which may lead to more serious faults.

The system’s advantage is majorly based on extreme simplicity, but that comes with a major disadvantage. The leakage level is directly revealed, and the intensity of fault maybe had to judge; that is why some people opt out of using such leak-down detectors.

Quality of Toolbox

Most leak down testers come with a toolbox that contains the device and other necessary components. The box can be made with different polymers of rubber or plastic.

It is important to get a tester with a resilient and long-lasting box. Leak down testers, especially the typical ones with pressure gauges, are not meant to be moved around without coverage when not in you.

Most pressure gauges are covered with glass; you don’t want it to drop and get damaged. Also, the toolbox is a form of protection from corrosion and even on the general scale.

Final Thoughts

Diagnosing engines have become so much easier and straightforward since leak down testers came on board. They give a clear picture of an engine's health with the percentage of air loss displayed on their gauge. After testing, whatever loss in the gauge tells you what's going on inside of the engine and if you need to open it up or not.

In conclusion, we've reviewed the best leak down testers in the market, with their respective features and compatibility with engines. By now, we hope you should have seen the one right for your engine. Good luck!

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