Tuesday 28 June 2011

Mistake in compression test

Hi,
I'd just like to highlight a mistake I made in the compression test. I was re-reading through the manual again and happened to come to the section on the compression test. I noticed that I missed out something.

The manual says to hold the throttle wide open while cranking the engine over. I forgot to do that.

Being curious, I wondered if it made a difference, so I removed one plug and hooked up the compression gauge and gave it a try. I got a reading of 150-160PSI (contrast that with past readings of 90 - 100PSI). So apparently it does make a big difference.

2 comments:

  1. Yes, hopefully no rebuild is needed!

    If you haven't found this site already, DansMC is always useful for double checking/extra reading. The tidbits of practical advice are useful.

    http://www.dansmc.com/compression_test.htm

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  2. Thanks Peter, and thanks for the link. It's always good to revisit Dan's site.

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