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1. 06:26 AM - SNF X-C (gary)
2. 06:05 PM - test flight for changing Bing main jets from 176 to 178 INNOCENT GLOBAL 0.0000 1.0000 -2.0210 (LarryMcFarland)
Message 1
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Cc: <stratus-list@matronics.com>
--> Stratus-List message posted by: "gary" <gkrysztopik@satx.rr.com>
...this never made the airsoob or stratus lists. same email as
on flysoob. trying again ...
I completed my move yesterday when I got my Stratus-powered Pelican from RI
to TX via Sun'N'Fun. This email is a little long (and it's the short
version) but I believe in sharing stupid mistakes if anyone can get
something out of it. Besides, I still need to figure out exactly what
happened and how to make it better.
I flew the whole east coast from RI to FL down to Fort Lauderdale without
incidence, with one overnight stop at First Flight Airport in NC to check
out the Wright Brothers memorial. I had a great trip and everything went
really smooth, including flying at 8500 over NY Class B.
I did an overnight visit at Fort Lauderdale then headed out on the two-hour
trip back north to SNF. That's where the excitement began. At about 4000'
over the everglades, the radio started blinking and there was a popping in
my headsets. Then, the panel went black and the engine got quiet. I
puckered up then hit the aux switch and the engine came back on. I got my
handheld out and took the nearest airport for a precautionary landing and my
first breath for several minutes.
I found a bad master contactor, and since my alternator overcurrent
contactor failed previously I figured it just went so I moved my bat and alt
cables to bypass it. Everything else looked good and an extended runup went
fine. It sounds quick but it was actually a few hours looking over the
engine and panel. I held my breath and headed out again.
About 15 minutes into the flight, my radio started blinking and my heart
stopped ticking. This time, I noticed my aux bat volt meter wandering
between 15 and 16 volts (normally between 13 and 14). I started turning
towards the nearest airport and sure nuff, everything got dark and quiet. I
hit the aux again, and lucky me the engine came on again. Got the handheld
out and landed without incidence.
I suspected the built-in regulator went so I pulled the alternator. I went
to an auto parts store and they tested it. It failed on the tester "when
the switch was on alternator but passed when it was set to generator". They
had no idea what that meant but it sounded like a bad regulator to me. They
didn't have a Suzuki Samuri alternator in stock but said a guy up the road
fixes them. Off to the guy up the road and he tested it. "Nothing wrong
with this alternator" he said. I asked to keep testing, and he got it
really hot under full load and it still worked. Maybe under vibration or
higher rpm? Dunno. Went to another auto parts store and they ordered one -
"two hours". They tested it and it passed on a third type of test stand,
this one fully automated. Not good. I took the new one anyway and kept the
old one for troubleshooting.
Went back and installed it, but the battery wouldn't come up after charging
so it was toast. Found the same size and replaced it. I also removed the
overvoltage circuit and removed a diode to ground on the field line from the
contactor. It's normally not good to make more than one change at a time
but I wanted to remove all in doubt and try to recreate the problem later at
home. Ran it up for a long time not feeling good that I didn't understand
exactly what happened or find and fix a hard failure. Told the tower that I
was going to keep climbing and circling for a while, and everything seemed
ok.
Headed to Lakeland again keeping alternate airports within range as much as
possible. Ran great and got to Lakeland a little eary. They close during
the airshow and open up for arrivals at 6 pm. So there I am circling Lake
Parker with a couple Cessna's for a while just staring back and forth at my
voltmeter then up at the tail of the guy in front. Finally we got released,
landed and I taxied for about a half hour to the "back forty" where they put
homebuilt camping. If I knew it was that far out and that they had
autoconversion parking I would have done that but I wanted to camp with my
plane.
I spent quite a while looking for a battery contactor (I had to disconnect
my battery to stop it from draining) and a lot of time looking at engine
monitors. I never finished my homemade one so it's either git 'er done or
buy new. I was hoping to talk to some smart people like you guys to figure
out some details but never found much help at SNF.
I'll have to take this over to the aeroelectric list and admit my mistakes
so I can figure it all out. I have the overvoltage circuit but had the
contactor bypassed (first mistake) because of that failure. My overvoltage
circuit breaker popped the first time (should have been a hint) which would
have pulled the "field" line down on the alt. Since it's internal
regulator, not sure what that would do. The battery was still good after
the first time probably because the contactor failed (going to retest it
today). The second time I guess it just fried the battery. I can try to
recreate the problem and decide on a solution after reading all of the
aeroelectric stuff including the Paul vs Bob battle that raged for weeks on
overvoltage protection. Hmmm, should have paid more attention to that one.
Oh ya, flew back from FL to TX over the next couple days and got some
confidence back although there wasn't one second where I didn't know exactly
where the nearest airport was. The swamps of LA where slim pickin's but I
was relaxed when I hit southeast TX and saw all flat open farmland. Got it
to my new home safe and sound, and I have to stay except for my stupid
mistake of having a partial overvoltage circuit and not having a good engine
monitor, that Stratus EA-81 just hummed along and I'm really happy with it
(yes Frank, after doing the RAM valve guide mod ;<} ).
I wish I could say the trip was uneventful but a dose of reality is good to
prevent overconfidence.
Fly safe,
Gary Krysztopik
Pelican/Stratus N522GK - 175 hours
San Antonio, TX
Message 2
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| Subject: | test flight for changing Bing main jets from 176 to 178 |
INNOCENT GLOBAL 0.0000 1.0000 -2.0210
--> Stratus-List message posted by: LarryMcFarland <larry@macsmachine.com>
Hi Guys,
It's been a month since the main jets were changed, but testing waited
for Sun n Fun and weather. Thought I should finally report the
results for those with a Stratus EA81 and Ram Performance heads.
Sunshine and tall overcast clouds were on tap today with just a few
sprinkles. About 2:00 weather was finally flyable with reported ceilings
of 3800 ft. I did preflight and twice checked the header tank for water.
Still pitched at 17-degrees, N601EZ lifted off at 2:30, climbed into the
south practice area and I observed the effects of changing the Bing main
jets from 176 to 178. A 180 main jet was tried last year and it caused
the engine to run a little rough. On climb out at high rpm the EGT never
exceeded 1400 deg F. Engine power seemed the same and it ran smoothly.
At 3500 feet I leveled off, pushed the throttle fully forward and
watched the tach reach 4950 rpm but no further. The richer mixture was
obviously cooler and yielded a little less horsepower. I adjusted
elevator trim to optimize airspeed and held a level attitude and waited.
The airspeed topped out at 128 mph, 5 less than before. EGTs settled to
1350 degrees F. and stayed there. At full throttle, oil temperature
finally reached my alarm set point of 250 degrees and the light came on,
so I backed off to 120 mph and the oil temp settled to 240 degrees F.
Cylinder head and coolant temps were 204 degrees F. Ambient air was
78-degrees F, which is hot for this time of year, but I was pleased that
the EGTs were lower with this 178 main jet. At a cruise airspeed of 120
mph, an exhaust gas temp of 1325 degrees F was a definite improvement.
Despite a slight loss of top end rpm, I'm really happy with the 601 and
Stratus Subaru at this point in time. Ram Performance said 1350 was a
good target EGT temp and Stratus said that 1500 would be a good max
EGT. So I think this 178 main jet will stay on and I'll continue to
watch it as the season changes.
The tower broke my focus with a warning for possible thunderclouds, rain
and severe convective in the area. Recalling last night's local
tornados, I immediately turned around and headed back under a much
darker set of clouds and a thick haze at 3000 feet. My landing was real
good and I used 23 to return to the hangars with 55 minutes on the
clock. With three quarters of the fuel used up, I'll probably drain the
rest and prepare for paint.
Larry McFarland - 601HDS at www.macsmachine.com
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