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Hi Steve,
I am no
expert and am far from engine start, but from what I have seen on this
forum I see that John has a plenum fed by the scoop. This may allow
the air to slow down and permit the heat to transfer more
efficiently. It also appears you have air trapped in the system
which will have to be purged. I think your oil cooler duct is close and
you might have to tweak it (K & W curve on the duct sides and/or
maybe increase the feed opening). It looks like you are making
progress. Keep us posted.
Joe Berki
Limo EZ
At 06:14 AM 9/20/2004 -0400, you (Steve Brooks) wrote:
Al,
I am running the cores in
series, and I agree that it appears to be insufficient cooling.
Since others are running the evaporator cores with no trouble. I
assume that the issue is air flow. John Slade seems to have no
trouble with his temperatures, and has the identical plane and
scoop. Actually I've added a front end to my scoop to get outside
the boundary layer, but still have high temperatures.
I have a P-51 style scoop that
I had put on earlier with the old cooling system. I removed it when
it didn't improve the cooling, but the old set up I think was beyond
help. Maybe I should try it with the new set up.
I was also wondering about any
other factors causing excessive heat from the engine, like timing.
I haven't tried to retard the timing any, but I know that in piston
engines, if you get the timing too advanced, it can result in allot of
heat.
Steve Brooks
- -----Original Message-----
- From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]On
Behalf Of Al Gietzen
- Sent: Sunday, September 19, 2004 3:28 PM
- To: Rotary motors in aircraft
- Subject: [FlyRotary] Re: Still high temperature
-
- The high temps are indicating insufficient cooling capacity ( I guess
that s obvious); which means insufficient air flow or too little heat
exchange area. If others are getting adequate cooling at the same
power with the same cores, then it is air flow. As I recall, you
are no longer running the coolers in series, but there still may be a
pressure recovery issue with your scoop, or just too small an opening;
more like the first.
-
- After a few runs it seems that the air should be purged. Do you
have a means of checking (confirming your temps to be sure there isn t
some boiling going on?
-
- Al
-
- Subject: [FlyRotary] Still high temperature
-
- I would appreciate input to a problem that I have. I just
overhauled the
- engine, and reworked the cooling system. I'm now using the A/C
evaporator
- cores for radiators. The problem I'm having is, that when I
take it up, I'm
- seeing coolant and oil temperature of about 210 degrees. That
is climbing
- to pattern, leveling off, and throttling back to low power. The
oil stays
- pretty much where it is, and the coolant come down just a couple of
degrees.
-
- When throttle back to land, the coolant and oil both come down to
about 180
- at touchdown. I taxi back to the hanger and shut down with oil
and coolant
- about 190-195, but after shut down, I get all sorts of gurgling
noises from
- the header tank, which is fed by the tap on the side of the
thermostat
- housing. The gurgling noises go on for 5-6 minutes, which would
seem like
- the engine is overheated, but while hot, it doesn't seem overly hot.
The
- other end of the header tank feeds coolant to the turbo, so maybe the
hot
- water is coming from it ? Maybe my header tank should be fed
differently ?
- Also at this time, after a short flight, there is only a couple of
cups of
- additional coolant in the overflow tank.
-
- I assume that the higher than desired coolant temperature, and the
gurgling
- noise are related. I pulled the water pump off today to double
check it,
- and all seems OK. The pump only has about 10 hours on it.
When I run it on
- the ground, and feel the radiators after shutdown, they are uniformly
hot.
- I put a furnace blower pointed at the scoop, and I'm getting very
even
- airflow through the radiators. The oil cooler, on the other
hand, has about
- 75% of the air going through the middle of the cooler, so I'm going
to have
- to add some deflectors in the plenum to push more air to the
outside. That
- seems to be a less significant issue at the present.
-
- Any thoughts ?
-
- Steve Brooks
- Cozy MKIV
- Turbo rotary
-
-
- >> Homepage:
http://www.flyrotary.com/
- >> Archive:
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