10 psi compression

Sweetmarie66

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Dec 29, 2017
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Hey folks! Been awhile since I was here, so the inline 200 in our 66 had a dead cylinder, was really odd, ran great the day before, did a dry and wet compression test here are the numbers in the attached photo with the plugs as well, why the H would it run great the day before then next day it had a dead cylinder, #3 ? Blown head gasket? I'm thinking this is a way bigger problem. rings for sure with numbers like that.
 
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rbohm

SN Certified Technician
Apr 12, 2002
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there are any number of things;

bad head gasket
stuck open valve

are two such items.
 

Sweetmarie66

Member
Dec 29, 2017
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Thanks man!, ya I'm going to pull it here in the fall, rebuild if necessary, then believe me I'll be picking you brain lol.
 

65ShelbyClone

Founding Member
Sep 9, 2000
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I once had a 289 stick an exhaust valve open by close to a quarter inch while I was driving. Tore it apart on the roadside and saw one valve lower than the others. With few other options, rapped on it with wood and a hammer until it closed, put the covers back on, and made it home. It's a wonder the pushrod and lifter didn't get spit out.

The heads were redone shortly after...
 
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