170 Dart compression advise???? please??

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Old Dart

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Hi, Nat from Canada, I've got a 68 Dart with a 170 that will idle all day until I drop it into gear. It almost felt like the torque converter was locked on, until I did a compression test. From the back of the engine to the front-
cyl 6 = 60
cyl 5 = 70
cyl 4 = 120
cyl 3 = 60
cyl 2 = 120
cyl 1 = 70
I realise that this could mean either rings, valves, or head gasket. I just don't know how to go about finding out. If anyone has any advice, I will pray for you to the mopar gods.
 
You can check for worn rings by squirting a little oil into each cylinder and let it sit for a while, then repeat the test. If the compression comes up, it's bad rings.
 
old old trick...mix a little water and Ajax and make it into a paste to put down the carb.....helps reseat everything. Not sure about engine longevity though.
 
yeah you may want to check to make sure that the valve lash is correct. If the valve are too tight, they wont close all the way and compression will be low.
Easy to remember for a slant 6; .010 clearance on the intake and .020 on the exhaust valve. Check them first and then do compression check.
 
at least .020 on the exhaust valve. no less. .022 would not hurt anything.
 
I just finished doing the oil in the cylinders trick, the pressure in every bad cylinder came up at least 20psi.
I was told that a bad head gasket might lower compression, but after doing the oil trick it looks like rings I guess.
Does anyone know if the oil in the cylinders could have helped the compression if it is a bad head gasket??? Or is there a way to test for a bad head gasket?? Sorry for the rookie questions, but I am hoping this is something that I can fix. I don't think that I'm ready to get into the block, and I'll miss that old 170. Thanks again for all your help!
 
Did you check your Valve lash ? I am a rookie and the tec's here don't mind at all to help us out OLD Dart, If the valves are not closing or opening all the way your compression will not be where it should be, and when you added the oil it took up room in the cylinder and brought your compression up.
Have you ever set valves before on a slant 6 ??
 
I've never set valves but very willing to try. Thanks to omahamoparguy, I have the clearance numbers.
Any advise for checking valve lash that could save me some study time???
 
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