Silicates

["Steven M Tucker" <EROSTRATUS@domain.elided>]

Silicates were determined to be the culprite for frequent water pump
failures for Porsche 928s with their aluminum alloy block & etc.

There are several on the market now that are silicate free.
You have to be careful especially now, many shops are simply filtering
antifreeze so they save on disposal charges and don't have to listen
to customers get upset at the cost per gallon.

I decided to switch to silicate free PolyPropolene Glycol coolant
(undoubtedly misspelled).  The two most ocmpelling reasons were the
silicate issue and, given Alfa headgasket issues, the fact that PPG is
somewhat less damaging than standard Ethylene Glycol if it is released
into the crankcase. (Of course I'm talking small amount/extremely
short term here, but insurance is insurance).

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