How important it is for the
engine block to be grounded?
It is really important, for many cars this is the intended return path
for the spark current. A bad ground in some cars can result in heater
core leaks.
I have seen (for instance) as the current finds an unintended path and
melts the solder on the core inlet/outlet. The owner of the car did not
know this until after the second heater core. In this case the connection
was just dirty after 100,000 miles of use.
Another example… when the block ground strap broke. The current
found the path of least resistance, which was through the emergency break
cables and melted the plastic sleeves redering the E brake useless.
Bottom line, always make sure the block has a good ground.
Rick
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