I think those fittings are 7/16-20 UNF, not 1/8-27 pipe thread...
From: Hal Faulkner [firstname.lastname@example.org]
Sent: 8/24/2007 5:13:29 PM
Subject: Re: [Spridgets] valve guides
Treat the 1316 casting just the same as the 12G940. You can block of the
air holes with 1/8 27 NPT allen plugs.
Your machinist can tell you if the guides are worn, he should have specs
how much play is permissable; however, for the cost of replacing them it
a pretty safe bet they are worn.
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