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Re: antiquatedfreeze (Propylene Glycol BTDT)

>I've used Sierra brand Propylene Glycol coolant in all of my personal
>vehicles since about 1993, and in all of my customer's cars since about
>1996-- with no ill effects to report.  Prestone now sells PG coolant
>too.  It's the same price as the national brands of EG coolant, cheaper
>than Dexcool, and non=toxic.

Evan's brand PG is non-aqueous. It is NOT miscible with water; in fact,
they hate each other (ask Igor about the "Olde Faithful" he had).

>Aside from flushing the cooling system (with water, through a tee I
>install in the heater inlet hose) before pouring in the PG coolant, I
>really don't see the need to do anyting else to "convert" to PG
>coolant.  PG is totally miscable (100% soluable) in water/Ethylene
>glycol-- so it's not the end of the world if you don't get all of the
>old EG coolant out.  The only undesirable traits the PG has, that I know
>of, are that it does not lower the freeze point or raise the boiling
>point as much as EG for a given concentration,

Not quite, see below

>and has a different
>specific gravity for a given concentration so that test equipment meant
>to indicate the concentration of EG will not give accurate readings w/ a
>PG/Water mix.  For just this reason, Sierra sells cheap (less than $2)
>eyedropper/floating ball style densitometers on the shelf right next to
>their coolant.  The upshot of this drawback is that if you live in a
>REALLY cold climate like Minnesota, Alaska, you may need to use a
>stronger than 50% mix.  
>From the back of the Sierra jug, and the back of a no-name EG coolant
>	Sierra Freeze	EG Freeze	Sierra Boil	EG Boil
>50%	-26degF		-34degF		256degF		265degF
>55%	-39degF		-48degF		260degF		267degF
>60%	-54degF		-62degF		261degF		270degF

Evan's boil, with no cap (zero pressure), 370 dF

Check www.evanscooling.com

>I have also yet to try Redline "Water Wetter" in a PG cooled car-- next
>time I order from them, I'll ask whether it's compatable with PG
>Have a cool summer.

A happy customer, with one year and 9k miles. Expect some heated mails from
Avi; he really had trouble with the stuff, though many others have used it
without difficulty.

cu, James
'87 4kq (alias "late-B2 90q")
'89 200q (K26, wood/8-gauge dash, torsen, aero handles, Procon10/no bag)
Boise, ID, USA     http://netnow.micron.net/~marriott