David,
This is a good topic for discussion. The problem of cooling system erosion
is not limited to aluminum heads. I remember in the 50's and 60's
particularly when I was in Southern California, that replacing freeze plugs
was a routine maintenance job. We replaced them with brass to help ward off
the a reoccurrence.
Today, this is not as great a problem since everything runs coolant (50/50
water and antifreeze). However, coolant can lose its ability to protect and
should be changed when that happens. The culprit here is electrolysis. The
cooling system becomes a battery, producing voltage which can also upset the
computer system since it uses the engine block for its grounds. A simple
check with a voltmeter can tell you if you are in an unsafe situation.
Testing for Electrolysis:
Test with the engine running and at operating temperature. Make sure that
all engine ground Straps are in place.
Using a digital voltmeter: Place the negative (-) lead to the battery
negative post and the Positive (+) lead into the coolant.
A voltage reading above 0.300V can cause pinholes in the heater core in a
short amount of time.
Check these web sites for more info... http://www.4s
com/fourseasons/tech_tips/tech_tips_English/AB350_Electrolysis_02.pdf
Proper ground circuits are a must in today cars, improper grounding
accelerates the electrolysis problem.
http://www.search-autoparts.com/searchautoparts/article/articleDetail
jsp?id=154932
Tom, Redding CA - #216 D/FCC
-------Original Message-------
From: Adin, David
Date: 8/5/2008 6:49:22 AM
To: LandSpeed List
Cc: panteras
Subject: [Land-speed] alum heads on the street
Since my knowledge of chemistry ends with "Salt, its not just for
margaritas." I must ask:
Alum heads - antifreeze -What should one do to prevent the chemical
(galvanic?) action in the cooling system??
Is antifreeze enough? Do I need a sacrificial anode?
Any tips/thoughts/theories appreciated.
David in Durango
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