Some vehicles may experience a gradual coolant loss over time. A very low percentage of cylinder head(s) manufactured with an embossed Castech logo may develop a porosity crack in a very specific area.
Inspect the cylinder head assembly to determine if the casting was manufactured by Castech. This can be accomplished by inspecting for their casting logo located on top of the intake port, under the rocker arm support rail and in the spring deck cavity portion of the cylinder head. If inspection reveals evidence of coolant witness marks (1), replace the entire cylinder head(s) assembly.

check this first while you pressure testing it,remove a valve cover.done a few of these,pretty common.
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Friday, July 10th, 2009 AT 2:43 PM