Leakdown test(er). Where to buy and suggestions please.

[gotta240]

I've always done compression tests on motors/cars i was interested in buying or trouble shooting on. From all i have gathered(not much) a leadown test is a more thourough/sure way of testing the motor. I have a few simple questions..

1. Where should i get a leakdown tester and are there any brands you guys prefer over others?

2. Are there ANY disadvantages of using a leakdown tester over compression tester?(other than ease of use?)

3. Any tips/secrets/things to watch out for when doing a leakdown on a motor you are interested in purchasing?

[gotta240]

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[statik]

leakdown tester can tell you a few things a compression tester cant. you could have great compression on all cylinders, but still have worn/failing rings, bad valve seals etc. There are no disadvantages to doing a leakdown, just realize that if the motor is sitting on the ground dry, you will get better numbers when the engine has actually run recently as the rings will seal better, so don't be discouraged unless its significant. Only trick to doing a leakdown is the pistons needs to be at TDC, so i usually pull all the plugs and place a long screw driver in the hole resting on the top of the piston. Crank the motor until you see the screw driver stop going up, thats TDC.

[gotta240]

Thanks for the quik/informational post! repped.