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Mark Romano
04-13-2006, 02:51 PM
"I have a 2002 5.7L vortec w/ 200 hours and compression in cyls. # 1,3,5 are about 100-110.
all other cyls about 175-200 psi. What could be the problem. Still runs graet..."

fastjeff
04-13-2006, 09:30 PM
"# 7 is okay? Having 1, 3 , and 5 be low would indicate an overheat on the left bank.

Jeff"

mark_r
04-18-2006, 07:15 AM
"OK , WHAT WOULD THE REMEDY BE?
PULL HEAD CHANGE HEAD GASKET OR GET VALVE JOB ON THAT HEAD ONLY?"

jimn
04-18-2006, 08:21 AM
"Was the compression checked dry at normal operating temperature, with all of the spark plugs out?"

mark_r
04-18-2006, 12:32 PM
"comp. was checked dry w engine warm and all spark plugs in except the one being checked.Then I squirted a small amount of oil in each cyl and checked again., went up about 5lb thats it."

jimn
04-18-2006, 05:21 PM
"I would recommend checking it again with all plugs out, in case an adjacent cylinder is helping a bad one. I ran into that on a 351 with a toasted head gasket, from being overheated and whoever replaced the gaskets using Ultra Copper sealant on the head gaskets and intake gasket. #2 &3 were bad (low 70's with plugs in but #2 had none and #3 had 15 lb with no plugs."