It seems that most temp issues are with oil. Mine are not with oil,
but with CHT's.
As you know (you have seen pictures), I have 2 smaller (6" round) oil
coolers, one on each side (mounted to the engine mount) with naca ducts and
short 4" to 6" long straight 2" inch scat duct to them. The scat duct is
connected via glass enlargers. On the outlet side, there are glass
reducers down to 4" scat duct, with the duct routed down to near the nose gear
front cover on the firewall. It as close to the lower cowl outlet
area that I could get.
The oil temps. are too low, especially in winter. It is difficult to
get the temp to 180. In summer, the oil temp is about 190 to 200 climb and
cruise. I tried (for winter) closing off one cooler with duct tape over
the cowl inlet to raise the temp and it didn't make any difference. Tried
it on both sides. I also removed the 4" outlet duct (reducers left on), to
let the outlet flow directly into the rear cowl area, with no change
noticed. In only one case, have I had a high oil temp; in Bend,
Or., giving a friend a ride after a previous flight. Outside
temp in the '70's. Never has happened again.
Now, if I could just get my CHT's down. I have to step climb with
that issue when at gross weight.
Gary Edwards
LNC2 235/320
----- Original Message -----
Sent: Friday, March 06, 2009 4:53
PM
Subject: [LML] oil cooling
|
All,
I am looking for suggestions on how to
lower my oil temps. I am running an IO 320 on the original 235 frame. On
warm days in a climb I have trouble keeping them below 220. I usually
have to flatten out the climb to cool things down if they get up to 230
or so. Once in cruise it is not a problem and they will settle around
210. I would like to get them down to 190 if possible. The problem is on
a 75 plus degree day when the airplane is already warm from flying and I
need to go again. I am picking up outside air on a naca vent on the left
side of the cowl. There is a 6" length scat tube (4"diameter) connecting
the cowl inlet to a glass expansion section that is connected to the
cooler.(see pics). It just dumps in the lower cowl area.
I am running
a Stewart Warner oil cooler that many have had success with.
I
have tried larger hoses to the cooler now using -8's and also removed
the 90 deg fittings I used to have to improve flow.
I suspect my
ducting and or connection to the cooler could be improved. I am looking
for suggestions that could be done without cutting the
cowl.
Thanks in advance!
Randy
L.Snarr |