flyrotary@lancaironline.net Mailing List Archive

Re ruined rotor housings, A bloke in OZ is way down the path of making sleeves to fit inside ruined rotor housings. He cuts out the inside level with the inside edge of the inner side O ring groove, then presses in a sleeve that makes the housing back to new specks, and give you a new inner O ring lip as well. Believe he is at the stage of testing the first ones now. Something to watch, and in the meantime do not throw any damaged rotor housings away. Neil.

From: Kelly Troyer

Sent: Saturday, February 07, 2015 9:17 AM

To: Rotary motors in aircraft

Subject: [FlyRotary] Re: 20B Engines

Thanks Mark........That is the info I was looking for............I happen to have a 13B Cosmo that has the later housings

and I had only read about the reinforced housings.........

Kelly

On Fri, Feb 6, 2015 at 6:49 AM, Mark Steitle <flyrotary@lancaironline.net> wrote:

Kelly,

I wouldn't hesitate to use an early 20b. The early 20b housings are plenty robust enough for a/c use. The beefier irons could be an issue if you're building a turbo race engine due to the higher loads imposed during up shifting and down shifting. We don't experience any of those loads.

I'm pretty certain that my 20b is an early model and I have not experienced any issues with irons cracking around the dowels. The weakest area is along the inner walls of the o-ring grooves nearest the water jackets. If your o-rings aren't to factory specs, you run the risk of cracking an o-ring wall which ruins the housing. Been there, done that. If you treat the engine with the same care you would a certified a/c engine, then you won't have any trouble with longevity.

Mark

On Fri, Feb 6, 2015 at 12:00 AM, Kelly Troyer <flyrotary@lancaironline.net> wrote:

Mark Steitle or other 20B Drivers,

I am looking at a 20B that looks to be an early one before they added additional

metal in the dowel/oil passage area of the iron housings because of some that I have

read developed cracks in this area in service in the autos I presume.......

Can you tell me if this a potential problem for the 20B in our aircraft use ?.......Also

can you tell me if your 20B has the later reinforced housings ?.........

--

Kelly Troyer