Rotary Compression Tester

Description

This is an electronical tool made specifically for all Wankel rotary engines made by Mazda, to measure the compression in each rotor chamber(and all rotors simultaneously in the higher-end variants). It accounts for variations in starter RPM and altitude, displaying both the raw(uncorrected) readings and the equivalent(standardized) ones.

It can measure the compression on every face of a rotor, display it in BAR/PSI/KPA, then measure the cranking speed of your starter and the atmospheric pressure.

All this information is used to compensate for RPM and altitude, giving you an equivalent result as if your test was taken at 250RPM and at sea level; this is how Mazda says it should be done. It takes into account how weak your car battery is, how worn the starter is, ensuring you get the most accurate result.

Using this device is no harder than taking the driver-side wheel off, removing two spark plugs, and inserting a sensor in each hole while spinning the engine over. The whole test takes about 10 minutes: 3 minutes for removing the wheel, 5 for the spark plugs, and 2 for the actual testing.

New! Now you can buy a version with 2 pressure sensors – and it will do both of your rotors during one engine cranking test!

There is also a version with 3 pressure sensors if you are lucky enough to own a 3-rotor 20B engine.

The classic 1-sensor version is still available as usual – and the newer models have all the features of the old one. But since most rotary engines have 2 rotors, it makes sense to have 2 sensors that measure at the same time instead of testing one, then moving the sensor to the other rotor and repeating the test.

The cable length is adjustable, allowing you to comfortably sit inside the car while cranking the engine. This tester can be used alone without extra help for both LHD and RHD cars. Please note that the 2-meter version works for RHD cars, but the wire will be shorter, making it harder to see the tester while cranking. A 4-meter version is available for better visibility.

It is of great help to prospective buyers or sellers – everyone wants to know what they are buying.

The tool has no limit on usage, though it has a 9V battery inside that will eventually need replacing. You should get at least 100 tests per battery, which should last a lifetime for most users.

After the test is done, cranking RPM and raw results (not corrected) are shown, followed by corrected results accounting for RPM and altitude. Units of measurement are in BAR, PSI, and KPA for both rotors.

The results are shown as following:

• Engine cranking RPM (acceptable range: 120 to 350 RPM)
• Uncorrected pressure results in BAR, PSI, and KPA for each rotor and each rotor face (total of 9 readings)
• Corrected results for RPM and altitude in BAR, PSI, and KPA for each rotor and each rotor face
• Sensor placement guidance (sensor 1 in rotor 1, sensor 2 in rotor 2, sensor 3 in rotor 3 and so on)

If you own a 20B and other 2-rotor rotaries, this tool will work on 2-rotor engines as well (just leave sensor 3 unplugged). Same for a 4 rotor tester, if needed it can be used on 1, 2, 3, or 4 rotors at once(just leave the respective channels with no sensor in them).