help on cylinder leak down test
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help on cylinder leak down test Doing a little make over on my 2000 SS. I am doing a leak down. How long should it take for 100 psi dry air to leak out of a cylinder? 
please help! When I brought it down I thought I had scorched some valves and they were a little pitted. Just added heads, 232-238 , 114 cam, new tranny with all the goodies, 3600 stall, long tubes and 4.10s. I sure would hate to tear it back down. 
By the way I do all my own work so labor is at least free. 
please help! When I brought it down I thought I had scorched some valves and they were a little pitted. Just added heads, 232-238 , 114 cam, new tranny with all the goodies, 3600 stall, long tubes and 4.10s. I sure would hate to tear it back down. By the way I do all my own work so labor is at least free. Thread Starter
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leak down
Originally Posted by derek_silvy
This does not help you... and I hate to get off topic, but how do you go about a cylinder leakdown test?
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Joined: Sep 2004
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From: Raleigh, NC
Well first off, you should try doing a leak down test the RIGHT WAY. Go buy/borrow a cylinder leak down tester!! With the correct tool you will only supply about 35-40 pounds of air into the cylinder. Up to 60% leakage is acceptable. Less than 40% is good. 100 pounds of air is most deffinately going to leak somewhere fairly quick, even in a good engine (rings would be the easiest place to leak). I do not see how your method of using a compression guage tells you much of anything. You need the right tool.
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Found the solution to the problem. Took my setup to a buddys 99 SS. Knew his blow by was minimal because of a rebuild and compression test. Hooked him up and it took his 13 seconds to drop to zero. Mine took 15 seconds so I know I'm OK 
. thanx God 
! By the way CSTICK is absolutly right. It would have been much easier with the proper tools but I didn't have the right tools and my current expenditures have left my reserves at an all time loooow. got to save enough for a dyno tune and a trip to the track. Thanx for the imput.
. thanx God ! By the way CSTICK is absolutly right. It would have been much easier with the proper tools but I didn't have the right tools and my current expenditures have left my reserves at an all time loooow. got to save enough for a dyno tune and a trip to the track. Thanx for the imput. Trending Topics
I just filled the cyl. to 90psi and turned the engine until both valves were closed.Theres a fine line between open/closed but after doing it u kinda know where your at when u hit tdc or just before it.
I had less than 3% in every hole both hot and cold.The only thing I wish I wouldve done is go forged pistons.The stockers rock (Hypers) until there warm but ring seal is awesome in my motor.
I had less than 3% in every hole both hot and cold.The only thing I wish I wouldve done is go forged pistons.The stockers rock (Hypers) until there warm but ring seal is awesome in my motor.
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Originally Posted by jazzz007
Found the solution to the problem. Took my setup to a buddys 99 SS. Knew his blow by was minimal because of a rebuild and compression test. Hooked him up and it took his 13 seconds to drop to zero. Mine took 15 seconds so I know I'm OK . thanx God ! By the way CSTICK is absolutly right. It would have been much easier with the proper tools but I didn't have the right tools and my current expenditures have left my reserves at an all time loooow. got to save enough for a dyno tune and a trip to the track. Thanx for the imput.
. thanx God ! By the way CSTICK is absolutly right. It would have been much easier with the proper tools but I didn't have the right tools and my current expenditures have left my reserves at an all time loooow. got to save enough for a dyno tune and a trip to the track. Thanx for the imput.David
