----- Original Message -----
Sent: Saturday, June 02, 2007 7:58
AM
Subject: [FlyRotary] Re: Prop loads on
engine
Bill, base on my experience and your rpm there is no
doubt you need the larger prop as you clearly recognize.
Here is something you may want to check.
When my Coldstart function got turned on (without a switch being moved - long
story) without me knowing it at the time - my engine would bearly run
with the manual mixture control turned full lean with both primary and
secondary on. When I turned off the primary injectors it ran fine
on the secondary only because, of course, there was 1/2 the fuel flow of the
four injectors. Your symptoms sound very much like
mine. One of my rotor EGTs would also nose dive. Why
just one, I am uncertain - you would think both.
The only thing I can think for you to check is to
put a voltohm meter between the pin to the cold start switch on the control
panel Pin 13 (probably could put it on the output pin of the EC2 pin
30 if that's easier) and ground. With both injector switches ON
there should be no ground at that pin it should show open on your voltohm
meter (or a high resistance). When you throw either injector switch off
then that pin should show a connection to ground. If it shows
a ground when the injector switches are OFF that could be your problem.
Actually, since I don't know the internal wiring of the EC2 this is just a
SWAG on my part. But, clearly if the cold start which functions when
that pin is grounded - shows a ground with both switches ON then I would bet
something is probably not right.
The other alternative is that one injector in the
primary set is sticking open intermittently at lower rpm?
Ed
----- Original Message -----
Sent: Saturday, June 02, 2007 8:27
AM
Subject: [FlyRotary] Prop loads on
engine
I have made my third test run trying to sort
things out. I concur on the need for a load on the engine. I have
borrowed a Sensenich (sp?) prop for the test runs, since my Catto prop has
not arrived yet. It is 76x60, and must be severely under propped (76x88 on
order).
I started the engine, throttle all the way
back, then one turn forward. Engine RPM on EM-2 ~ 2800. Engine was running
rich, max number of bars on mixture indicator. Tried leaning knob adjustment
and it helped some. Engine seemed to bog some so gave it one more turn
forward, then started playing with injector switches. Turning off the
primaries, engine smoothed out, and RPM shot up to almost 7000, this is with
very little throttle opening! Mixture went lean, and leaning knob had
significant effect. RPM would climb rapidly when I richened the mixture. I
cannot get anywhere close to the 22" manifold pressure for some of the
adjustments called for in the EC-2 manual. Will have to wait for the more
aggressive prop.
You can see that Rotor 1 is bogging down until
I shifted to Secondaries only on the EGT plots.