Mailing List flyrotary@lancaironline.net Message #46388
From: Lynn Hanover <lehanover@gmail.com>
Subject: Water temps
Date: Fri, 12 Jun 2009 06:13:35 -0700
To: <flyrotary@lancaironline.net>

Allow me to speculate:

I suggest that watertemps above 210 are out of bounds. Thus it should be looked at as something you got away with, not a number to look for in normal operation. I would retorque the stack cold if I had seen those numbers. (235)

Here is some dyno stuff for a 12A bridgeported engine with two 36MM chokes in a Weber carb.

6500 RPM (because there is no point in testing a racing engine below that), and even then it is to put up a starting point for a curve.

Torque 139.6 foot pounds.

HP 173.3

EGTs 1515 front 1491 rear

BSFC .666 (the devils own)

oil temp 162 (160 is ideal) Above 160 costs power due to rotor face temperatures.

Oil pressure 99.9 (relief set at 110 pounds)

Water temp is always 180 controlled by the cooling system on the dyno.

Air/fuel  12.3  (slightly rich is fine as it helps cooling and sealing)

I would expect to get as much as 10% more power from a 13B.

Lynn E. Hanover

Interesting questions: Is that data at full throttle?

You can hold cruise RPM at an A/F of 15?

 

 

Today I ran the engine .9 hour, .7th's static at 4700 rpm -  13B, Marcotte 2 - l redrive

 

Water temp         235               OAT  61            Spring hasn't arrived above the 44th parallel

oil temp              215                                        yet

Exh. temp         1500

Prop speed        2350

MP                      28

oil pres                75

air - fuel         15 to 1

fuel press             42

 

.2 hr high speed taxi

 

Water temp         188

oil temp               160

Ex temp             1400

Prop speed         2500

MP                        28

fuel press               42

 

The static engine run temperatures climbed quite a bit with the cowling on and working on the programming I didn't notice that this was happening, but they went right down when I idled back.

I will have to pull the cowling in the morning and check the redrive, it appears the seal is leaking on the flywheel side.  With no support from Marcotte, I may have too much 80w in the gearbox.  I believe that the temperatures look good for flight.  JohnD

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