Exhaust Flange PN's and help with Pancake Muffler

[fenderjw]

Hello All.
I just rebuilt my C145 engine and expended copious amounts of cash doing so.

Now, while reassembling the A&P and I discovered that the exhaust system needs some attention. He and I agree that I need to upgrade to a Hanlon-Wilson style system, but due to the engine rebuild, the supply of cash to address the problem has been seriously depleted.

I have the original pancake style system that can be utilized (for the next couple of annuals at least) once a couple of issues are addressed. I need to replace the flanges that hold the stubby exhaust stacks to the #3 and #4 cylinders (the middle ones) but I cannot find a part number for the flanges. I have checked the Continental overhaul manual, the Cessna 170 Illustrated Parts Catalog (IPC) and every other document that I could lay my hands on but none of them show the flanges themselves so I am having a devil of a time finding a part number.

Lastly, do any of you guys have an old left hand (LH) pancake muffler lying around that's still in decent shape (espeially the flanges and the rolled end of the risers)? My LH muffler is still serviceable but JUST BARELY.

I realize that I need to upgrade the muffler system but that option is not available to me right now.

Any help appreciated, 9998A's been down since Memorial Day.

Jim Fender
Whiteplains Plantation (SC99)

[Bruce Fenstermacher]

Jim not many here still using the pancakes but I'm an exception so I know what your talking about.

The flanges are readily available from Spruce in both mild steal and stainless steal. http://www.aircraftspruce.com/catalog/e ... langes.php

If your pancakes are like mine they are made with stainless and so that is what you need.

BTW the mufflers are interchangeable from side to side except for one thing. And that is the bevel on the exhaust exit. If it comes down to it and you find a good one but the wrong side I'd run it with the bevel facing back. Half the 170s have this wrong as it is.

And should you decide to get rid of the pancakes I might be interested in them as my partner has vowed to be the last person running them.

[sfarringer]

And I thought I was the last person to finally give up on pancake exhaust!

Seriously, except for having to spend the money, I'm very glad I finally changed to the Hanlon-Wilson type, for two reasons:
1) I got tired of patching it every year, and
2) The cabin heat is sooooooo much better.

But, I don't think I disposed of the pancake parts, so I will check to see if the center stubs look good enough to be worth sending to you.
However, I won't be able to check until this weekend.

[fenderjw]

80

[fenderjw]

Mr Fenstermacher
Thanks for the info.
Checked with spruce yesterday and the flanges are on the way. By the way, in what manual, booklet, online catalog, etc. can one find a diagram of the exhaust system with applicable part numbers listed?

Sfarriinger
I'd really appreciate it if you'd check your exhausts for me. I really need the left muffler if its serviceable. The center stubs on my muffler are fine, but the front and rear risers are nearly burnt out where the end of the riser tube mates to the cylinder (the rolled end of the tubing is nowhere near flat and is really thin).

Thanks again for your help.
Jim

[Bruce Fenstermacher]

Jim,

The parts are listed in the IPC for each aircraft. If your looking for the Hanlon Wilson parts for your aircraft you would have to look at the 52 B model IPC for serial numbers for the year 1952. The system for '52 and the one used to retrofit earlier pancakes uses the same muffler right and left and baffles for 2" scat. Later B model systems could be used but they use different mufflers right and left and the correct baffles use 3" scat. The heat scat system would have to be adapted. (The A model IPC might have the correct Hanlon Wilson parts as well I can't remember and don't have one at the moment to check)

From memory the pancakes will only have one part number for eash side because the entire system is one part. (the center connector might be a seperate part).

As for parts used to make exhaust parts such as the flanges, there aren't any parts numbers because they were not sold by Cessna that way. You can probably search some older Continental IPCs and find the flange part numbers.

[sfarringer]

Jim:
I haven't come through for you yet.
I only have one of the two pancake sets that I used to have, still in my possession.
The better of the two sets(the set I used up until two years ago), I now remember that I abandoned it in my mechanics scrap stainless steel pile. It probably is still there, and he will check and probably get back to me in the next few days.

My original set is still in my scrap pile. The worst part of the left side is the inlet riser (for #2 I think), which has a crack at the flare where the flange clamps the tube to the gasket. This flare could be fabricated on a new stub and replaced if you had to.

I can attach a picture if you want.