Diesel Doctor – Compression Case Study – March 2021
The Diesel Doctor can identify a number of different problems including cylinder leaks, incorrect timing, injector/pump issues, valve leaks, blow-by, poor power balance, restricted inlets and more.
In the following example, high cylinder pressure variation was observed mainly due to cylinder 5; which exhibits low compression.
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Reasons for this could be valve leaks, tappet setting, blow-by (rings or liner) or an inlet restriction.
Investigation revealed that the input valves were clogged with carbon which was caused by an oil leak building up deposits.![]()
The exhaust valves were unaffected.
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The carbon was removed before running another test. You can see below the amount of carbon that had clogged up the input valve.![]()
After cleaning the Doctor system shows compressions are within an acceptable level, as shown below.
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If you would like to know more about the Diesel Doctor and how it can help your ships diesel engine then get in touch here.