Subject: Rotary exhaust problems
From: ACRE NL
Date: 2/10/2002, 7:08 AM



Can't the exhaust port liners be removed and replaced by driving out a drift
pin?
Brian Trubee



Its tricky but it has been done. I think the engine must be disassembled.

Paul Lamar


I replaced mine. The pins are very hard and can not be saved, unless you
destroy the housing.
Bulent


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Old message from the CD.

Subject:        Exhaust port diffusers
   Date:        Tue, 30 May 2000 16:32:02 -0700
  From:        Paul <rotaryeng@earthlink.net>


Bulent Aliev wrote:


I replaced  the steel sleeves on my housings with less restrictive ones from
junk housings. The roll pins don't come out easy at all. On the good housings I
started drilling out with  progressively bigger drill bit until the pins spun
and came out, but the pins were history.  They are hardened steel and will chew
up few drill bits. On the junk housings I made two cuts on the side of the pin
with the saw and knocked out the aluminum with the pin in it. Later pulled the
pin on the wise. I tried to buy the pins but had no luck with the dealer or
after market ones since the Mazda pins are metric and hardened steel.



Those are some drastic actions there Bulent. Why did you not just take it
somewhere and have them pressed out (in). Were the exhaust diffusers
not drilled all the way through on your engine for the roll pins?
I'll take a look at mine when I go to the hangar today.

Failing that I think a pin extractor could be
made from a C clamp. Use an angle drill to drill a small hole in the
fixed pad part of the clamp and put a short pin in there with a little
smaller diameter than the roll pin. Grind some of the pad away on the C clamp
so it fits well to the inside of the exhaust insert. Weld or braze a very
short piece of tubing about 1/4 ID 1/2 inch OD  and 5/16 long to the self
aligning  pad on the C clamp screw.

This tool should extract and save the roll pins.

Paul Lamar


Bulent Aliev wrote:


The roll pins do not go all the way through the stainless sleeve Paul. Hope you do
better than me. I did all that at Ed Heishman,s very well equipped machine shop, and
we could not come up with better way. Good luck!



Yes I just found that out. I stand corrected. Blind holes! 
Perhaps you could use an angle drill from the inside of the diffuser.

Paul Lamar

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