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Thanks, Mike.
Appreciate the input on the use of NPG in rotaries.
It would be nice to know if the racer's 13Bs used stock cooling system
components - frequently racers do not (higher capacity pumps, larger radiators,
etc) , but then sometimes the rules require them to use stock cooling
systems.
Ed
----- Original Message -----
Sent: Thursday, February 02, 2006 12:27
AM
Subject: [FlyRotary] NPG has been used
successfully-Ken Welter's Coot
Just one more data point. Al Wick asked if there was
anyone else that had used NPG besides Dave Leonard.
I recall Ken Welter
(rotary powered Coot amphib.) used NPG several years ago. He had no
complaints about its cooling ability and he was running an old Ross redrive at
3.17:1 (no, not 2.17) making LOTS of horsepower. He said (IIRC) the only
reason he went back to EG & water was that if you ended up doing some
field repair work on your bird you can not just throw in some water in the mix
to make it home. NPG is supposed to be run at 100% with as much water
removed as possible before pouring it in. (Note: I understand this is
not the case with NPG+)
The real problem with NPG in our rotary powered
birds is you can't walk into any auto parts / wal-mart / seven-11 to get an
extra gallon of the stuff to get you home. You can find EG or just water
anywhere.
One more data point while I'm here. Rob Golden of
Pineapple racing in Portland Oregon swears by the stuff. Rob has been
rebuilding and racing rotaries very successfully for over 30 years. I
have not talked to him in over a year but he used to send every engine out
with only NPG and I believe he required it for the warranty. Now of
course he sells the stuff so there is that bias on the fly in the ointment.
Neither of these above points addresses the super cooling issue that
in theory seems to be able to turn NPG in the radiator to jelly. Once
again we are left to do a thorough test. Those of us like Dave who like
the idea of flying into high cold places like Mammoth Lakes to go skiing
(sorry Dave..boarding) P-)
may need to plan on a winterization kit
like they use in the great white north, i.e. duc-tape over the cowl
inlets.
Okay, I've rambled on enough. Talk amongst
yourselves....
Mike
Mike McGee, RV-4 N996RV, O320-E2G, Hillsboro,
OR
13B in gestation mode, RD-1C, EC-2
At 19:36 2006-02-01,
you wrote:
Well, I'm not ready to agree with
that conclusion yet. And who say's we need to keep the cooling system
stock?
Mike
Ed Anderson
<eanderson@carolina.rr.com> wrote:
- Thanks for your assessment,
Monty.
- Scares me a bit that we all (more or
less) agree that the NPG is probably not well suited to the stock rotary
coolant system {:>)
- Ed
- ----- Original Message -----
- From: M Roberts
- To: Rotary motors
in aircraft
- Sent: Wednesday, February 01, 2006 8:35 PM
- Subject: [FlyRotary] sutability of NPG for rotary engine
use
<<< snip >>>
- In short:
- The 13b was developed to use
water/glycol as a coolant.
- To properly validate NPG you
need a dyno and a lot of thermocouples, plus a way to measure the mass
flow of the coolant, pressure drops, pump power, and the heat transfer
coefficient.
- Anybody got that laying around
in their hangar?
- Do you want to be a guinea
pig?
- I would not use NPG.
- Monty
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