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Leak down question

Shorthorse

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I decided to do a quick leak down test before I put my car back in the trailer. The engine was cold. The test was done at 90 lbs. All cylinders came in at about 7% except for #8. That cylinder read about 2%. I turned the motor over again and did the test. It read the same, about 2%. The heads have been done since the last time I did a leak down test. I've never seen just 2% on any engine I've ever tested. So my question is, would that reading indicate anything I should be concerned about?
Thanks.
 
Isn't it best to test with an engine that's warm and at least close to operating temp? And I wouldn't complain about the 2% and don't think I've ever seen one that good either. Do you know if any oil leaked in from maybe a valve stem seal?
 
Isn't it best to test with an engine that's warm and at least close to operating temp? And I wouldn't complain about the 2% and don't think I've ever seen one that good either. Do you know if any oil leaked in from maybe a valve stem seal?
It is best to test a warm engine but I was taking a lazy mans shortcut. I was mostly just looking for consistency or some anomaly. I put a scope in that cylinder and there was nothing unusual.
The car had not been run for two weeks.
 
It is best to test a warm engine but I was taking a lazy mans shortcut. I was mostly just looking for consistency or some anomaly. I put a scope in that cylinder and there was nothing unusual.
The car had not been run for two weeks.
Supper round cylinder and ring gaps are at the minimum gaps is all I can think of lol
 
2% is terrific. 7% is good too. what I've found thru testing is the more worn an engine is the more the difference between hot and cold becomes. good ring seal and valve seal hasn't shown any big swings between hot and cold in my testing. have a bad cylinder and you should see a noticeable swing from hot and cold.
 
It sounds like very a healthy result when comparing the numbers but I guess the very low reading is what your concerned with - Id wonder about the accuracy of my gauges on the tool and maybe a way to test the gauge itself?
 
It sounds like very a healthy result when comparing the numbers but I guess the very low reading is what your concerned with - Id wonder about the accuracy of my gauges on the tool and maybe a way to test the gauge itself?
I have had several gauges to 'test' one with and if they are the same, then I'm good....
 
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