i would recommend further ducting exit air to a low pressure area near the lower bottom, area and checking it with a differential pressure guage to ensure at least 5" pressure differential. Then it will work.
On Fri, Jul 30, 2010 at 1:53 PM, Bryan Wullner <vonjet@gmail.com> wrote:
Ok Guys. Here is a picture of the new oil cooler and new position in the airplane. It was upfront and now its in the back and I went from 7 vane to 9 vane. Will be test flying it this weekend. Will post the results. Fingers crossed.
Bryan
On Sun, Jul 25, 2010 at 10:36 AM, PAUL HERSHORIN <paulhershorin@bellsouth.net> wrote:
I can't answer your question on a carb. I am sure that other lancair pilots with Carb's can answer this question.
Paul
Sent: Sat, July 24, 2010 10:13:15 AM
Subject: [LML] Re: My airplane is running HOT
I don't have fuel injection I'm carb'd. I don't think there is any way to adjust fuel flow except with mixture knob in cabin correct?
I had very highoil temps. I was drawing the air from #3 cylinder baffle. I closed off this air vent and mut a nicho (sp) duct in my top cowling into the oil cooler. This lowered my oil temps to 200-210, I increased the fuuel flow throw the Servo 3 times and was able to lower the cilinder temps--now on these hot days in south Florida I am able to climb to 6500 with the cylinder temps below yellow--if I am held on the ground for an extended period I will take off and climb to 1000 or 1500 level off an and cool the clyiders and then go on up to flight level. I never reduce fuel flow until at flight level.
Paul Hershorin
360
To: lml@lancaironline.net
Sent: Wed, July 21, 2010 5:08:42 PM
Subject: [LML] Re: My airplane is running HOT
I'm starting with the changing of oil cooler to a larger one and relocation to engine bay with scat ducting to it off the baffling. If that doesn't do it I will move on to the next idea. My hopes are that my oil comes down and helps the cht's too. I also hope that closing off the large hole in the front baffling from old oil cooler placment helps with cht's
Bryan
On Jul 21, 2010 1:01 PM, "Chris Zavatson" <chris_zavatson@yahoo.com> wrote:
Tom,
The differential required is dependent on the power(heat) produced.
In the link below is both a copy of some Lycoming minimums to produce a 'smoking hot' 435 and 500 deg F CHT. It also contains the pressure differentials I recorded several years ago on my plane.
http://www.n91cz.com/Pressure/PlenumPressure.pdf
Chris
Chris Zavatson
N91CZ
360std
To: lml@lancaironline.net
Sent: Tue, July 20, 2010 3:31:09 PM
Subject: [LML] Re: My airplane is running HOT
Bryan,
You can also use an airspeed indicator, if you have one handy.
The key is that both "tubes" that pick up the pressure have to be configured as if they are static pressure ports. This means that the air has to flow over the opening(s) in the tube at 90 degrees, like the static port on the fuselage.
An easy way to do this is to use a short piece of tubing with holes drilled in the sides, like a soaker hose for the lawn. Smash one end of this tube completely and connect the line back to the sensor to the other end of the tube. Point the closed end of the tube directly into the airflow. Do this to both of the tubes. One would be at the oil cooler inlet, the other at the outlet. You will now sense the difference in the local static pressure at these two points. You can do the same thing anywhere else in the engine compartment that you like. For example, you can measure the differential pressure above and below cylinders to ensure you have adequate cooling flow. Chris Z., is about 5" of water pressure the figure Bryan will want for cylinder cooling?
If you are using an airspeed indicator, you will have to google for the conversion of speed sensed to pressure in whatever units you like. Same for some other pressure measuring device.
For my purposes, I designed, and 3 of us built, an electronic 4-channel sensor that can display data from one channel at a time in the cockpit during flight. I do need to have a secretary on board to take data readings and flip the switch between channels.
Goog luck,
Tom Thibault
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