oil pressure gauge marks

chickeneater

New Member
Aug 18, 2013
35
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0
Portland
just got done rebuilding engine, and as a sanity check, want to know what that first dash in the stock oil pressure gauge means. about halfway up the gauge there is a tick for 40, and below that, im assuming 20? the gauge isnt linear and im not sure why they omitted the reading for the first tick.

thank you!