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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.

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.

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.


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.