snips.
I have used Evans coolant for several hundred
hrs without a pressure cap and just vented back
to the burp tank and had no problems with it, I
am now using Sierra at 60 percent and I am using
a 7 lb cap and have never run over a 7 lb cap in
1300 hrs of flying and I fly at high altitudes of
10'000 plus all the time and have had the Coot to
16'000 ft once so I doubt that the pressure cap
had anything to do with Dave's problems.
What ever the problem was it had to be with
the freeze up cracking the radiator or the block,
it could be it cracked the block bad enough that
it filled the block with coolant and caused the
oil pressure loss.
Ken Welter
It is interesting Ken is getting these results. This to me says
something. Evans claims they have improved the conductivity by 32%. The reduced
heat transfer from the metal to the Evans propylene glycol coolant is not having
the predicted serious result of higher metal temperatures around the combustion
chamber. They could be higher but not high enough to affect the spark plug life
or melt the metal. At least not at the HP level Ken is running his engine. That
is the good news. My guess is his engine generates HP in the range of 170 to 190
HP. It remains to be seen if it is still going to work in the higher HP regions
of 200 to 250 HP.
"NPG+ WATERLESS COOLANT ELIMINATES BOIL OVER, CORROSION AND ELECTROLYSIS
NPG+ OFFERS 'POUR IN' INSTALLATION - BETTER HEAT TRANSFER - AND STILL "SAFE!"
npg plus 1 gallon NPG+ is new coolant providing dramatic improvements in heat
transfer and viscosity that make the new fluid a "pour-in," not requiring
changes to cooling system components. Conversion to NPG+ waterless coolant from
the use of conventional antifreeze and water coolant mixes, to take advantage of
the benefits of non-aqueous engine cooling, is now simple to accomplish.
NPG+ waterless coolant virtually eliminates boil over in gasoline or diesel
engines - the waterless coolant allows engines to tolerate running hotter,
without boiling over, and allows the cooling system to run at very low or no
pressure. Because there is no water in the system engines operating with NPG+
will be free from corrosion and electrolysis, and the engines will run well no
matter how hard they are driven or how hot or cold the environment is.
A blend of non-aqueous ingredients, NPG+ retains all of the benefits of Evans
original NPG coolant, while improving upon its thermal conductivity by about 32
percent and reducing its viscosity by about 65 percent. It is perfectly suited
for the demands of any hard working engine, and there are no plumbing or pump
changes needed to use this coolant.
A cooling system according to Evans technology uses a non-water-based, high
boiling point coolant (over 350º) and controls the temperature of the coolant
substantially below its boiling point. This is in sharp contrast to conventional
water based coolant systems that operate near the boiling point of the coolant.
In conventional systems, locally generated coolant vapor may not condense but
rather form an insulating barrier between the coolant jacket metal and the
liquid coolant, causing hot spots to develop."
http://www.evanscooling.com/catalog/C_npg1.htm
Here are some picture of Ken's air intake and rad.
Also a chart of coolant properties I believe was uploaded by Bill Schertz
if memory serves me well. Unfortunately the properties of Evans NPG + are not
listed.
Paul Lamar
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