The Cessna 120-140 Association Forum

I finally received the 150 exhaust system and have installed it. I have the old pancake system for sale if any members are looking for one. It is serviceable, no cracks, but has had numerous repairs in the its lifetime. I removed it from a 0-200.
I can email pictures if anyone is interested.

Hello,
I just recieved my new exhaust system too. Did you take any pictures of your new install when the cowl was off?
I would be interested to see those. Planning to have the new system installed next month.
-Sam

Still waiting for the scat tubing and some bolts from ACS to complete the install.

A couple interesting points for the conversion is that a new tail pipe brace ( C150) is required. The STC from taildraggers shows the scat for the carb heat to come from the right side which on my plane has the scoop. The installation with the pancake muffs had the carb heat coming from the left side which does not have a scoop. I thought I might have to have a scoop added but then reviewed my 0-200 STC which says specifically not to use a scoop for the carb heat, says it lowers the temp too much. I suspect the STC is assuming a C-85 or 90. I'm going to run the new scat the same as it was on the old system, right side with scoop to cabin heat, left side with no scoop to carb heat.

Blaine wrote: "...a new tail pipe brace ( C150) is required"

Blain, did you find a tail pipe brace easily...and, at a good price? There used to be several on Ebay and in fly markets but I'm not seeing them these days...one recent one was on Ebay with asking of $599.00 . Mac

$599! I sure hope not!

Blaine:

FWIW I would approach the scoop situation carefully. IIRC there is a spec requiring the carb heat system to have the capability to raise the heated air a certain number of degrees F above the ambient temperature. Think the Luscombe folks had to install internal baffle plates inside the heat muff to get sufficient temp rise to meet the spec! In your part of the world, don't think you want to be lacking - that ice could ruin your day!! Typically, in getting an STC. one has to have addressed all the engineering aspects. 2c

Prof John C may offer a learned comment - hopefully.

Edd

8482 wrote: ↑Fri Apr 24, 2020 1:46 pm $599! I sure hope not!

Yep...sure hope there's a good one around @ a good price! A new Cessna part (0450340-1) is in stock and available from Hill Aircraft in Atlanta...for...get ready: $1,591.00. In looking around Ebay there seem to be none right now. There are some good serviceable laying around in "someone's" shop, of course -- just gotta find them. One source may be Atlanta Aircraft Salvage -- email is: sandy@aaeparts.com. Good luck! Mac

Blaine:

Once again, stuck my foot in my mouth - my apology! Reread your comment - don't see how I can delete my comment - have to chalk it up to a "senior, senior moment"! Where's Prof John C to bail me out again?

However, IIRC isn't that brace just a Vee shaped piece of 4130 tubing with flattened ends with holes for clamps and bolts - one that could be "owner produced" - having the measurements?

Edd

4004 wrote: ↑Fri Apr 24, 2020 8:21 pm Blaine:

Once again, stuck my foot in my mouth - my apology! Reread your comment - don't see how I can delete my comment - have to chalk it up to a "senior, senior moment"! Where's Prof John C to bail me out again?

However, IIRC isn't that brace just a Vee shaped piece of 4130 tubing with flattened ends with holes for clamps and bolts - one that could be "owner produced" - having the measurements?

Edd

Edd, the OEM ("straight") exhaust utilized the VEE ("triangle"?) bracket, forward attachment to the rearmost oil sump stud -- pipes exited rear of cowling. I believe that the "150 bracket" is attached forward of the sump & is a longer, curved, extending L & R 4130 tubing that attaches to the tailpipes that exit through cowl bottom. There's gotta be a LOT of them around (...lots of 150s over the years, for sure)...but, even so, I've been surprised at the prices they seem to bring...when they can be "found". The 150 exhaust STC is a fantastic answer to the inevitable deterioration of both the OEM straight exhaust and, of course, the OEM Pancake exhaust...but, the cost & hassle in finding the tailpipe bracket can sometimes add some unanticipated challenge/cost. Mac

Chris Smith at KRN Aviation services has them new for $795. Edd, you are correct, mild steel so was able to "modify" the original one and it works just fine.