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The REASON that Cessna added this COWL BAFFLE SEAL around the carb box intake, is because the "L"-models and up have a propeller spacer, and the fiberglass cowls on the L and up years have the cowl further away from the filter frame. They didn't re-design the carb heat box with a longer scoop, they just added the seal assy. to fill the 2-3" gap.

Will there be any major problems with air flow if the baffle seal is removed? I can't see $600 for this piece of plastic and baffling material. I'm missing 1 complete side. Taking it off.

If the baffle frame is removed, then it means the engine cooling will be impaired.

For those who don't know, engine cooling is done by high-pressure ram air entering the cowl through the regular inlets, flowing through the cylinder fins to the low(er) pressure below/behind the baffles, then exiting through the opening in the lower cowl around the nose strut.

The difference between high pressure and low pressure is what drives this cooling flow of air. I seem to think the difference is only 4"-5" of water.

With the baffle around the air filter missing, then it means ram air is (can?) enter the low-pressure side of the engine, reducing this difference and the cooling flow of air through the engine.

How much of a difference? I don't know. But, operating on the theory that "parts left off don't cost or weigh anything and never need replacement," then I would think Cessna would've left it off if they could.

For those interested, here's an article on engine cooling design, and how to make your own, inexpensive, "water manometer" to test cooling pressure and effectiveness.

http://eci.aero/pdf/EngineCoolingProblems-SAE.pdf

Mine has been missing as i said earlier for 8 years. I do not believe it has resulted in any heat issues or cooling problems for me. Anecdotally well over half the 150's I have inspected have been missing this baffle.

HEY!

I just noticed the N number of your plane.

Your bird used to have blue instead of red.

Just thought you might like to know that.

I have been experiencing carb ice problems and some high cht problems on the number 1 and 3 cylinders. i noticed a hole in the carb air box baffling toward the number 1 and 3 side. After reading many articles on carb ice and knowing how the top of the cylinders needing higher pressure than the lower side of the cylinders, makes the possiblility of cowling air leaks even next to the carb air box a real issue. As one person mentioned that the later 150's with a prop extensions require this seal.

Old thread but wondering if anyone eventually came up with the CAD file to recreate the air intake baffle plastic frame? I have been unsuccessful in finding even a beat-up old one to copy so I can do an owner manufactured part.

My C150L is equipped with a JPI900 so I do know what is happening with the CHTs and EGTs. A piece of the frame broke off completely and my CHTs went up. When I can contact my IA I will explore making a part out of Kevlar which I will mold over a wooden block that will be cut to the shape of the inside of the frame.

Aerofairings in Canada has a direct replacement "The A105S150 is designed for the C150M..." and the total cost shipped is $211.15can or about $165.00 USD.