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Bill,
Yes that is correct. I find it best to completely
remove the wire to do this test. They can be delecate so wiggle them gently
in different directions while watching the ohm meter. Usually if there is a
problem it is at the connector, all though it can be anywhere along the
wire. The ignition wires have a certain resistance per foot that you should
look for. I don't know what that resistance would be because different brands of
wires have different specfications but as you check each wire you will get an
Idea what to expect. While you have them off check every inch for
damage sliding your fingers over the surface. See if you can feel any
anomalys that might be hidden under the surface coating that may indicate a
break or compromise of the wire in some way.
I know you will find the problem
eventually.
Robert
----- Original Message -----
Sent: Wednesday, January 09, 2013 1:59
PM
Subject: [FlyRotary] Re: Aeroquip hose
changed to hiccup
Robert,
I will check that the
next time I am at the airport. I am using the stock Renesis wires and
igniters. You just wiggled the wires with the VOM
connected??
Bill
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Rob
Sent: Wednesday, January 09, 2013 12:51
PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Aeroquip hose
changed to hiccup
Another thing you might
check.
I had a similer problem to yours
in my fuel injected Ford V6 BD-4 with Tracys EC2 and EM2. For about a year I
was plagued, while flying, with a brief miss with a jerk from the
engine at random times even hours apart. It would mostly happen at higher
RPM's then cruise, but sometimes at cruise. I checked everything I could think
of.
My problem was that one or two
of my ignition wires (MSD's 8.5mm Super Conductor wire set,
brand new no less) had some intermittent connectors. I discovered this by
checking the resistance of each wire while working the connectors a little bit
to see if the resistance fluctuated excessively or even became an open
circuit. Once I fixed these intermittents my problem was solved.
I know how unsettleing this can be
while flying. I hope you find your problem.
----- Original Message -----
Sent:
Wednesday, January 09, 2013 8:38 AM
Subject:
[FlyRotary] Re: Aeroquip hose changed to
hiccup
A problem that mimics a poorly wired VR sensor,
but
-only happens
occasionally,
-with various levels of
"response"
Bill, if you haven't done so already, I would
suggest changing the wiring to the VR sensor completely. It sounds to
me like a textbook example of the worst sort of electronic malfunction you
can have…an intermittent open. You'll never find it under normal test
conditions, and it will manifest at the most inopportune times. The
only way to completely rule it out as a failure scenario is to completely
replace the circuit path.
On Jan 8, 2013, at 11:42 PM, Bill Bradburry
wrote:
No, I have the 2.85
gearbox. I have the MT electric prop, so I fly WOT and use the prop to
govern the engine speed.
I have changed the
plugs with no effect. The mixture is fine when this is
happening. Fuel pressure also. I had an incident once on take
off like you describe where the plane was backfiring like crazy just after I
lifted off. I had the mixture too rich. I dialed it back and
everything smoothed out. This is different. It doesn’t really
backfire. It is a thump and it jerks the engine and plane. You
can hear and feel it. It seems to be a single thump and it has varying
degrees of violence. Some are just a little miss and some are so bad
it shakes everything. These are less frequent, but they are bad enough
that I don’t think they are good for the PSRU, prop, or engine
mount.
That is why I have
been bugging Tracy about the
change for the EC-2. I have my fingers crossed that this will fix
it. :>)
Bill
B
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