quote:
Originally posted by Ray H:
Ah, the persistant myth of 2-EH "softening plastics" raises its ugly head yet again. I spent an entire evening researching a half dozen chemical companies worldwide on the net which produce 2-EH for industrial, cosmetic, pharmaceutical, and food preservation purposes over a year ago to check this out, and it's baloney. 2-EH can be used to formulate plasticizers, but is not, itself, a plasticizer. To illustrate, glycerol can be used to formulate nitroglycerine, but is not, itself, an unstable explosive. The companies selling 2-EH ship the stuff in its hydrated concentrated form in plastic bulk containers - how much a plasticiser could it be?
GM's gasket problems did not originate with DEX-COOL®. They were the result of fitting a plastic intake manifold, itself exhibiting minimal thermal expansion characteristcs, to aluminum heads in a V configuration device subject to very high thermal expansion characteristics. (GM chose plastic as a coolant carrying crossover channel for its insulating properties to aid engine warm-up for minimal emissions.) Think of a V "growing" apart but bridged with a relatively constant dimension plastic piece. The only thing that could "give" was the sealing gasket. Whether the latest intake manifold gaskets from GM and Felpro for these problem engines have solved the problem remains to be seen. Time, not claims, will tell the tale.
