It is really hard telling, especially without a compression test before the head was pulled. There is no sure way to tell if the head gasket was bad once the head is off. (unless it is obvious looking at the gasket) Intake gaskets can leak so it is possible. However, with the tendency of these trucks to have head gasket and head crack problems that seems more likely. My 79 had a tiny hairline crack near the #2 exhaust valve seat that made it blow massive amounts of steam. The head gasket actually looked fine.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
