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How long should a cylinder stay compressed?
At TDC maximum compression with the engine off, how long should the air stay pressurized in a good running engine before escaping? I can hear the air coming out in about a second or so.
3 Answers
- DanLv 52 years ago
At TDC the compressed volume is very small and it won't hold pressure very long at all. The valves should seal almost perfectly - listen in the intake and exhaust to check, but it's impossible for the rings to seal completely. The time will depend on engine size and it's compression ratio, a second or so may be perfectly normal. Like a compression test I would think it's more important to worry about uniformity across all cylinders if you're using this as some kind of test.
- Anonymous2 years ago
A cylinder should stay compressed for approximately 1 minute 37 seconds