Cylinder Leak Down Test

Air leaking out of a cylinder can be an indicator of a variety of engine problems. To pinpoint the source of the issue, perform a cylinder leak down test. In this video, Master Technician Mark Kenyon of Garage Gurus guides you step-by-step through this important diagnostic test.
Mark shows the proper technique for attaching the test hose and cylinder leakage tester and what to listen for when doing this test. Count on Garage Gurus to help you get your vehicle repair done right.



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[larrygibbons]

I’ve watched several other leak down test videos but when I watched this one I finally understand how the test works. EXCELLENT INSTRUCTIONAL VIDEO !!!

[clomputech]

I have been looking for information about this and after several confusing videos, this one finally helped me to understand how it works. Thanks 👍

[andrewbowser]

Hey Mark, took your Ignition course in Pittsburgh. Just want to say awesome video and tech tip. You and all the Garage Gurus are literally that — Gurus! Thank you for all the valuable knowledge 👍

[wcjcnc]

Wow, someone that actually knows how to perform a cylinder leak down test. Almost every video on YouTube is WRONG. It’s nice to see someone do it right. Thank you.

[japfourme]

I use the balloon method to determine when the pistons on its compression stroke.

[ericm]

Super helpful video and everything clearly explained. Thanks!!

[nelsonruiz]

Buen video exelente explicacion
A todos los motores se les puede aplicar 100 psi ?
Gracias x su respuesta

[FDLTDChris]

Thanks for the sharing the vid, very informative 👍👍

[puremayhemFTW]

If you have good compression from compression test then does that mean you wouldn’t need to do a leak down test?

[khaniftikhar]

Very helpful demon stration thanks alot

[renejacques]

If you started at 90psi in the inlet, how does it go up to 92 percent, if anything it should go down; right? I don't understand how it's a 5-6% leakage. Please clarify.

[timchruch]

I have a 4 cylinder in my car. Would I need to check all 4 and if so do I take out one plug at a time or take all 4 out then do the test?

[patrickdubuc]

Do u have to disconnect the upper radiator hose to do this test?

[Dynasty-sy]

Why would the engine spin because of the ratchet? I am sorry if this is a stupid question I want to perform this test but have never done it before.

[joseortez]

What about if you hear air from the oil cap ?

[scottwooster]

At TDC is the air puff coming out of the hose strong? I need to do this on a 351 Windsor. Never done it before but I have the tester.

[pauldahlke]

What about middle and bottom Dead center? The only reason why I say that is because taper in the cylinder wall ?

[SoldouttotheTruth]

So basically if I am wanting to buy a used car, and I went to a supposed mechanic, I don't want this test done. Because if the person is pretending they are a Mechanic, they will damage what may have been a good engine!