That is good data,
Dennis.
I changed my plugs
this afternoon (I had a set of RX-7 plugs so that is what I used) and will fly
tomorrow. I will check the stability of my manifold pressure then.
I installed a plastic fuel filter in the line a while back. I have two
manifold pressure lines from the intake manifold. Each of them is “T”ed
into the lawnmower fuel filter and then they separate at a “T” and go to the
two inputs to the EC-2 controller. If it is not stable, I will try your
idea of a partial blockage of the filter inlet.
So with 95% the
hiccup is not totally eliminated. How often would you say you now get a
hiccup?
Bill
B
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Dennis Havarlah
Sent: Tuesday, September 04, 2012 11:00
AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Intermittent
hiccup
I've been using iridium plugs in
my Renesis for 300 hrs. I am using the iridium plugs that come from the
factory. When I changed them at 250 hrs I did not notice any change in
performance! I use regular car gas with ethanol and very seldom do I use
100 LL.
I had a hiccup every so often
and could not eliminate it until I put damper chambers in my manifold
lines. I used the small plastic fuel filters for lawnmowers (Purolator
F21124). This eliminated at least 95 % of the hiccup and my manifold
pressure is very steady. With the dampers my manifold pressure
varies about 0.1 in hg up or down in cruise. Without the
damper it would vary as much as 0.3 to 0.4 in hg in
cruise. I plugged the inlet of the filter with JB and drilled a hole
about 0.032 inch in diameter through the epoxy. Check your manifold
pressure and see if it is stable.
----- Original Message -----
Sent:
Tuesday, September 04, 2012 1:29 AM
Subject:
[FlyRotary] Re: Intermittent hiccup
Yup, I suspect
SAG. I go through plugs very quickly.. like 25hrs. No
cleaning will help as the electrode is worn out. You can milk them to
100 hrs but its not really worth it. SAG gets really bad by 75
hrs. The platinum onea last an extra hour or two. Have not tried
the iridium. Always change plugs before a long trip. Also, they
come out much easier after only 25 or so hours.
--
David
Leonard
Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net
On Mon, Sep 3, 2012 at 8:46 PM, Bill Bradburry <bbradburry@bellsouth.net>
wrote:
Has anyone ever
noticed a hiccup associated with sparkplug SAG? I have a hiccup that
is occurring at random intervals from seconds to several minutes.
Sometimes it is pretty mild and sometimes it shakes the plane! I also
seem to be down in power and I am beginning to suspect plug SAG. I
have 38 hours with the Iridium plugs plus a lot of time over the years of
running the engine before flight. I had a couple instances of flooding
which required that I take the plugs out and sandblast them to get them to
fire. Just drying them out didn’t work.
Thoughts??
Bill
B