wrote:=20 Dave, When you switched to Evans coolant, was it at 100% Proplyene Glycol? Bill Schertz KIS Cruiser # 4045 --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html ------=_NextPart_000_000C_01C61A96.0E2D8A80 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Dave, I want to look up properties of = NPG at my=20 hanger later today, I am sure that it is miscible with water, so any = residual=20 coolant/water left in the system would just go into solution, not boil = and force=20 the coolant out.

Things to consider in your post mortem. =

1. Possibility of stop leak plugging = channels=20 in radiator. This could have an increased effect due to #2=20 below.

2. Increased viscosity of NPG vs water = -- You were=20 flying in very cold conditions, and therefore when you are circulating = the NPG,=20 it can cool off a lot in the radiator -- this will make it more viscous, = at the=20 cool end of the radiator, then this increases the load on the pump that = is=20 trying to push the fluid around the loop. The temperature in your engine = may=20 have been climbing before indication on your guage, depending on where = the guage=20 is located.

3. Increase load on pump -- could this = cause belt=20 to start slipping/overheat/fail -- look for signs of hot rubber on belt=20 pulley.

I will dig out information on NPG this=20 afternoon.

Bill Schertz
KIS Cruiser # 4045

----- Original Message -----
From:=20 David=20 Leonard
To: Rotary motors in = aircraft

Sent: Monday, January 16, 2006 = 11:53=20 AM

Subject: [FlyRotary] Re: = Anatomy of an=20 almost crash.

Bill,

This is a good point and something I have been thinking = about. The=20 added NPG was 100% PG but there was obviously a little bit of aquious = PG left=20 in the system. I tried to burn it off during my hour long ground = run,=20 but the temp never got very high (toped out at about 180). That = little=20 bit of water may have boiled over and forced out the evans...

Someone else brought up the 7 psi cap with altitude. That = is also a=20 possibility - actually a combination of both.

On 1/16/06, William=20 <wschertz@ispwest.com>=20 wrote:=20

Dave,

When you switched to Evans coolant, = was it at=20 100% Proplyene Glycol?

Bill Schertz
KIS Cruiser # 4045

--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members= .aol.com/_ht_a/vp4skydoc/index.html=20

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