Like a compression test, a leak down test is accomplished by replacing a spark plug with the tester hose. A compression test is typically done prior to a leak down test and is an easy way to determine the internal health of your engine A compression tester measures the condition of your engine's piston rings, valves, and valve seats
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If these components are wearing evenly and the engine is in good condition, each cylinder should have over 100 psi of compression.
If you stopped reading right now, a novice might choose a compression tester
Compression leak tester hooks up to air compressor (provide yourself) can help to detect common engine faults such as worn piston rings, worn valves, cracks in cylinder walls and blown head gaskets Leak down tester gauge also equipped with 18 rubber hose, ar2000 pressure regulating valve, american type air plug and aluminum body.
