Rick-
INTERESTING! Couple of thoughts. Before you modify your inlet openings, try
putting some vanes in the plenums hung off the top. I have not done that,
but it will be my next step if I still have cooling problems. My thought wa
s that they would be about 1.5 inches deep and run from the front to just f
orward of 5 and 6. If that doesn't do it, you could put some deflectors on
the vane to deflect more air toward the heads. The vane worked so well in m
y cobra head that I think it may help here too. The air coming into the ple
nums must be very turbulent as is. My plenums are back on the plane and now
on to the oil cooler. I may have told you that I split my shark's tooth al
ong the sides and made the opening about 1/2 inch higher. Both that, and my
cooler is 11.5 inches wide, so I have some hope for it. Also, did you add
the holes and plenum on either side of the shark's tooth to cool the oil pa
n directly? I have it on mine and oil temps have been OK. I built it this w
ay, so I can't say that made the difference, but I remember reading somewhe
re that cooling the pan directly helps. John probably told you too that he
worked around the problem by mounting the cooler directly in the cowl. When
he takes the lower cowl off, he needs to un hook the cooler from the hocke
y puck. We need to open a photo sharing site somewhere. My pictures are 5 G
B each, so e-mailing them does not work well. Any thoughts?
Jim Puglise
----- Original Message -----
From: "AirEupora" <AirEupora@sbcglobal.net>
Sent: Monday, July 16, 2012 11:15:59 AM
Subject: Europa-List: N120ej trails and tribulations
After some very short flights I have finally gotten N120EJ up for a 46 minu
tes flight last week. I=C3=A2=82=AC=84=A2m still having some heating
problems, but am getting closer to solving them. Bud Yerly, Jim McCormick,
John Lawton, Jim Puglise have been a big help. I knew when I bought the Jab
iru that I'd have heating problems, but for the 10K that I save by buying t
he Jabiru I figured I could do a lot of modifications to the cowl and engin
e if need be.
One area is the plenum chambers for both sides. I have the type with the sp
ark plug wiring and CHT wiring running inside. The first modification was t
o the plenum chamber. There is not a lot of information out there for insta
lling the baffles in the plenum. Bud recommends not using any, but I had in
stalled some. I had to cut these out completely and my dealer, Jim McCormic
k, said I had installed them wrong. I then installed three dams =C3=82=C2
=BD=C3=A2=82=AC=EF=BD across both front cylinders and mid cylinders p
lus a 1=C3=A2=82=AC=EF=BD dam over 5 & 6. I have since cut these down
to 1/8" on the front two cylinders on both mid cylinders. I have 1/2" on t
he two rear cylinders. These are vertical to the air flow. Not sure why, bu
t that=C3=A2=82=AC=84=A2s what Jim McCormick recommended. I have also
installed the inter baffles that Jabiru stated that I did not need. I have
also wrapped a piece of aluminum around 5 and 6 to get more air moving acr
oss the fin area.
I have four inch openings on the Canadian Cowl that I'm using. I found out
after I installed them that John Lawton had gone to five inch openings. I h
ave modified the shark tooth or NACA duct for the oil cooler. Trying to fig
ure out a method of using this NACA duct and keeping the oil cooler attache
d to the engine had been a real challenge. I think I have modified this one
piece five to six times. I have what is called an 8 bar oil cooler. It is
about the closest thing to aviation type oil cooler. The last modification
was wrapping the oil cooler with duct tape and waxing it so I could make a
fiberglass mold. Once I had the mold made I placed it in the lower cowling
and designed it to be glued into place so air could not escape around it, b
ut had to go through it. I built a duct behind the oil cooler as recommende
d by a good friend and that has help a lot. I noticed after doing all this
work that my cowling had dropped =C3=82=C2=BC=C3=A2=82=AC=EF=BD I fle
w it this way and the oil temps !
came down and stayed down. I then went back and figured out what was causin
g the drop in the cowling and fixed that, but that caused the oil cooler op
ening to move away from the oil cooler about =C3=82=C2=BC=C3=A2=82=AC=EF
=BD on the bottom. I flew it that way and sure enough the temp came up.
One area that I might work on is making a cowl flap for the oil cooler duct
. Not sure how to do it right now. It will have to be part of the airframe
and not the cowl. More on that later, if and when I do it.
I=C3=A2=82=AC=84=A2m planning on putting a raised ring around the ope
nings for the air intakes. Right now this is a flat area and I have been re
ading some data that shows that I can increase the flow into the plenum cha
mber by doing this. There is a dam on 1 & 2. I have made a ramp so that the
air will flow up and over these dams. The temps on 1 & 2 are good right no
w, but the ramps may cause them to run hot.
One thing that has helped a lot is the black box viewer on the MGL Odyessey
II. It gives me the data in one second packets. The air temp, altitude, RP
M, manifold pressure, oil temps, oil pressure, CHT=C3=A2=82=AC=84=A2s
, EGT=C3=A2=82=AC=84=A2s, etc. It is a great tool.
Well, it time to go back to work on the Europa/Jabiru.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=378396#378396
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