X-Virus-Scanned: clean according to Sophos on Logan.com From: "David Leonard" Received: from mail-ig0-f173.google.com ([209.85.213.173] verified) by logan.com (CommuniGate Pro SMTP 6.1.10) with ESMTPS id 8606733 for flyrotary@lancaironline.net; Sat, 23 Apr 2016 12:54:58 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.213.173; envelope-from=wdleonard@gmail.com Received: by mail-ig0-f173.google.com with SMTP id m9so36386847ige.1 for ; Sat, 23 Apr 2016 09:54:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to; bh=VwspV56YLMAH/l5lu3zjYloDONfQOOEyb69BGCq5Es0=; b=yoeWpr9iuYnUXjuMV9d/Qhfc0EqO+FWOQh/iFjD9fpQdz9NbKpjmYB3i5evfsV25dw 7Xnn9xbJ8EnuV13St1P4dUCMwv4OJVcJu4HBu0Phdfxh0ImhQtfz0FI8iVAXq/eNZNNt 7g1rl/JGvPo+0V2CtHw9MLIkkHbmGbKR1ekcLB4+embLhvhN37jgSvY5vfXFYrh9afiH SzR8GmkTRSAdaeOpY9qpf/5KC3klvk2qA6isbKn4pSSfZ949/3gxiZzwBZVde5oUPoMl 4lQE2FBectWJ/ghzOlH8PC1DB74ggDV9932Lq8SlD6xVYwKZJ/eAv4QOKEEwvPCKjBip y1aQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=VwspV56YLMAH/l5lu3zjYloDONfQOOEyb69BGCq5Es0=; b=F9+OGhO1EdNEloeBFhTn4SYFUvLkDXXIhv7T7VAMZFDOvgaZQ8HumPMaLNjzE8lp5D /TRSqF9MEwT9BPlxcj17T7c1TZFlg5I8362Y/K28RIVcmVyzYg+3FJE6uW3dvo3fGMr2 gtytieS4tDRSgnTKEautKP4+9fFeWLVqmD/Zt5PNUxZDpH62JBFWjE+3lLN5oRHcde6b vkjoMHrq/qGfcvXBeB6sh4Vq05gC060xv1w5skJojoat5HX8nbdOuekbuiOHPjy0fh+N zo8xMSxBvHftnjKxYJ7DnYLrm4GIjIBUygPB49ZucAPvXY9gmBTVAPGiBqFeQbGZ3ba6 M0wA== X-Gm-Message-State: AOPr4FVYpQGTh2pJYOBctlDj2ByLsMllgS4WfIY0+mWOTiZCyctlRaLJfbtBKs4JQjq79y0NgvLd3OlNEnZsag== MIME-Version: 1.0 X-Received: by 10.50.25.137 with SMTP id c9mr3569170igg.84.1461430481145; Sat, 23 Apr 2016 09:54:41 -0700 (PDT) Received: by 10.79.69.132 with HTTP; Sat, 23 Apr 2016 09:54:41 -0700 (PDT) Date: Sat, 23 Apr 2016 09:54:41 -0700 Message-ID: Subject: Re: Not the water jacktet, Corner seal buttons? To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=047d7bdca50cb165ad053129cc9e --047d7bdca50cb165ad053129cc9e Content-Type: text/plain; charset=UTF-8 Thanks for the Great review Lynn. As usual it should be saved in the archives forever. Thanks for all the comments everyone else too. I guess I should give a little more background on what I am seeing. Keep in mind that I am not figuring this out for the first time. My plane now has almost 900 hrs on it. Formation team, coast to coast, Reno racer, blah blah.... I am not talking about a small coolant leak somewhere either. Rather, everything is working fine and I am flying along and for no particular reason it suddenly shits all the coolant out the overflow past the 20# cap, leading to a deadstick landing at my home field. Afterward it still passed a leak test and will hold coolant pressure indefinitely. A short test flight before the re-build showed exhaust gasses gathering in the coolant system. It always does this to a small degee, but now it is much much worse - making cross country travel unsafe. Thinking the problem is an o-ring that finally got tired (last rebuild was about 250 hrs prior), I set upon a quick rebuild to just replace the o-rings and other rubber bits. To address Lynn's other points: Bleed holes at the top of the engine - check Covering the exhaust holes in the center iron - check, I think. The holes in the center housing are covered by the intake manifold. At the first rebuild I put potter's clay in the (dead end) passages, but it has long since disappeared. I don't think I ever had nozzles on my turbo rotor housings. I will be more careful about this issue on my next rebuild. Coolant - I am back to running 50/50 since I don't have overheating issues, my coolant temp runs 140 to 170 and peaks at 190 in the worst of conditions. But perhaps I would be better off with a higher water percentage to help prevent nucleate boiling and/or carry more heat away.. Silicone in the gasket groves. I used hylomar on my first rebuild but it was a pain. I have been just using Vaseline to hold the o-rings in place for the build. Seemed to work in the past but I Lynn says it, I will use GE Silicone to create a lasting seal. Side seal clearance. I did not replace the side seals this last rebuild and I could tell the clearance was not zero. It is definitely a contributor to my oil blow-by problem. Note to self - Just replace the seals when rebuilding. But all that stuff is getting more and more expensive lately. Lapping the Irons - I suspect that this is really my main problem both in terms of coolant and oil blow by. Wish we could just buy new ones. Once lapped I assume the Teflon o-rings become too fat and we have to go back to the stock ones, or even custom? sealing the legs of the rotor housing to prevent the seeping of hot oil.. this one bit me this time. I didn't do it and have seeping oil. Good thing I am about to do another rebuild anyway.... Another thing I didnt do was install the rubber buttons in the corner seals. Every time I tear down an engine they are long gone (especially the ones from RWS) so I figured they are not particularly needed. Since they are a pain, I skipped it. But now me thinks that there was a reason that I had to tear down the engine, and a reason Mazda included them in the first place. Lynn? Thanks for all the help everyone! David Leonard Turbo Rotary RV-6 N4VY On Fri, Apr 22, 2016 at 11:58 PM, Lehanover wrote: > > There are a number of methods used to blow the coolant out of a Mazda > engine. The most popular is actually overheating the engine by not removing > every spec of air from the cooling system. Many bubbles form in the top of > the cooling jacket. They do not move unless the engine RPM produces ample > coolant velocity. > As in a take off or taxi test. Then they form up un front of the high > mounted water pump and cavitate the pump to a standstill. Seconds later > there is no coolant to be found. Drill a hole in the top of the center iron > and install a bleed valve. Can be a Shrader valve with a metal cap. This to > leave open while filling with coolant so as to let said air out of the very > top of the engine. > > Coolant means distilled water. 10% glycol. One teaspoonful of Dawn > dishwashing soap or Redline Water wetter per bottle instructions. A bottle > of Barsleak. Yes that brown water with the Rat poop in it. If it is good > enough for a $100,000.00 Cosworth V-8, then its good enough for a Mazda. A > 22 pound Stant pressure cap and a recovery bottle so you can see where the > fluids went. > > Note that the rotor housings act as though they are made of hard rubber. > If one is only slightly warped it goes flat when the stack is torqued up. > No problem. If a iron is warped it is scrap. You can lap facing surfaces of > Irons against each other. This where minimal wear has been observed. For > heavy wear you can > have an automotive shop take off a few thousandths, then lap the piece > against its partner to remove most tooling marks. You can also do a great > job with a cleaning tank using kerosene and an air powered random orbital > sander. Glue on some 320 wet or dry paper and sand the wear surface under a > stream of Kerosene. > The little circles are great for holding oil. Once clean check for cracks. > > > And now into the weeds.......Many schemes have been tried in the pollution > control area. Most involve exhaust gasses being loose inside the rotor > housings where compressed air from an air pump was fed into the exhaust > stream through two steel nozzles that project into the exhaust port. This > air came from a port in the center iron that is covered by the intake > manifold. (In most every case). Those nozzles must be plugged. > The supply port in the center iron must be covered. The nozzles do not fit > tight and may leak fresh air into the exhaust stream and supply a cracking > and popping sound that confuses the tuner and Oxygen sensor. > > The center iron should match the coolant openings pattern of both rotor > housings. On assembly add a thin coating of GE 100% silicone tub and tile > sealant to the faces of the land areas that hold the "O" rings. Works great > to cure the tiny leaks and be sure to put it on the down legs clear to the > pan rail to keep oil from seeping out when hot. I use the same GE silicone > to seal the exhaust flanges to the engine. Stays leak free until you pry > off the exhaust system for service. If there is no gasket, it cannot fail. > I have used a copy of the RX-2 RX-3 cooling system since 1980 Never an > overheated engine. I can publish that drawing if anyone wants it. > > Set the side seal end clearance to zero, not .002" to 004" as seen in some > books. If both side seals and the gives you as close to advertised > compression as is possible. Quick starts even when hot. If the side seals > and the corner seal pop back up after being compressed, then it is perfect. > Good to 9,600 RPM. > > More on bullet proof Rotaries as soon as I remember it.......The last > racer is available and the spare (250 HP) engine is available. > > Lynn E. Hanover > > > > --047d7bdca50cb165ad053129cc9e Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Thanks for the Great review Lynn.=C2=A0 As usual it should= be saved in the archives forever. =C2=A0

Thanks for all= the comments everyone else too.=C2=A0 I guess I should give a little more = background on what I am seeing.=C2=A0 Keep in mind that I am not figuring t= his out for the first time.=C2=A0 My plane now has almost 900 hrs on it.=C2= =A0 Formation team, coast to coast, Reno racer, =C2=A0blah blah....

I am not talking about a small coolant leak somewhere eit= her.=C2=A0 Rather, everything is working fine and I am flying along and for= no particular reason it suddenly shits all the coolant out the overflow pa= st the 20# cap, leading to a deadstick landing at my home field.=C2=A0 Afte= rward it still passed a leak test and will hold coolant pressure indefinite= ly.=C2=A0 A short test flight before the re-build showed exhaust gasses gat= hering in the coolant system.=C2=A0 It always does this to a small degee, b= ut now it is much much worse - making cross country travel unsafe.

Thinking the problem is an o-ring that finally got tired (= last rebuild was about 250 hrs prior), I set upon a quick rebuild to just r= eplace the o-rings and other rubber bits.=C2=A0 To address Lynn's other= points:

Bleed holes at the top of the engine - ch= eck

Covering the exhaust holes in the center iron = - check, I think. The holes in the center housing are covered by the intake= manifold.=C2=A0 At the first rebuild I put potter's clay in the (dead = end) passages, but it has long since disappeared.=C2=A0 I don't think I= ever had nozzles on my turbo rotor housings.=C2=A0 I will be more careful = about this issue on my next rebuild.

Coolant - I a= m back to running 50/50 since I don't have overheating issues, my coola= nt temp runs 140 to 170 and peaks at 190 in the worst of conditions.=C2=A0 = But perhaps I would be better off with a higher water percentage to help pr= event nucleate boiling and/or carry more heat away..

Silicone in the gasket groves.=C2=A0 I used hylomar on my first rebuild = but it was a pain.=C2=A0 I have been just using Vaseline to hold the o-ring= s in place for the build.=C2=A0 Seemed to work in the past but I Lynn says = it, I will use GE Silicone to create a lasting seal.

Side seal clearance.=C2=A0 I did not replace the side seals this last re= build and I could tell the clearance was not zero.=C2=A0 It is definitely a= contributor to my oil blow-by problem.=C2=A0 Note to self - Just replace t= he seals when rebuilding.=C2=A0 But all that stuff is getting more and more= expensive lately. =C2=A0

Lapping the Irons - I su= spect that this is really my main problem both in terms of coolant and oil = blow by.=C2=A0 Wish we could just buy new ones.=C2=A0 Once lapped I assume = the Teflon o-rings become too fat and we have to go back to the stock ones,= or even custom?

sealing the legs of the rotor hou= sing to prevent the seeping of hot oil.. =C2=A0this one bit me this time.= =C2=A0 I didn't do it and have seeping oil.=C2=A0 Good thing I am about= to do another rebuild anyway....

Another thing I = didnt do was install the rubber buttons in the corner seals.=C2=A0 Every ti= me I tear down an engine they are long gone (especially the ones from RWS) = so I figured they are not particularly needed.=C2=A0 Since they are a pain,= I skipped it.=C2=A0 But now me thinks that there was a reason that I had t= o tear down the engine, and a reason Mazda included them in the first place= .=C2=A0 Lynn?

Thanks for all the help everyone!

David Leonard
Turbo Rotary RV-6 N4VY
=



On Fri, Apr 22, 2016 at 11:58 PM, Lehanover <flyrotary@la= ncaironline.net> wrote:
=
=C2=A0
There are a number of methods used to blow the coolant out of a Mazda= =20 engine. The most popular is actually overheating the engine by not removing= =20 every spec of air from the cooling system. Many bubbles form in the top of = the=20 cooling jacket. They do not move unless the engine RPM produces ample coola= nt=20 velocity.
As in a take off or taxi test. Then they form up un front of the high= =20 mounted water pump and cavitate the pump to a standstill. Seconds later the= re is=20 no coolant to be found. Drill a hole in the top of the center iron and inst= all a=20 bleed valve. Can be a Shrader valve with a metal cap. This to leave open wh= ile=20 filling with coolant so as to let said air out of the very top of the=20 engine.=C2=A0
=C2=A0
Coolant means distilled water. 10% glycol. One teaspoonful of Dawn=20 dishwashing soap or Redline Water wetter per bottle instructions. A bottle = of=20 Barsleak. Yes that brown water with the Rat poop in it. If it is good enoug= h for=20 a $100,000.00 Cosworth V-8, then its good enough for a Mazda.=C2=A0 A 22 po= und=20 Stant pressure cap and a recovery bottle so you can see where the fluids we= nt.=20
=C2=A0
Note that the rotor housings act as though they are made of hard rubbe= r. If=20 one is only slightly warped it goes flat when the stack is torqued up. No= =20 problem. If a iron is warped it is scrap. You can lap facing surfaces of Ir= ons=20 against each other. This where minimal wear has been observed. For=20 heavy=C2=A0wear you can
have an automotive shop take off a few thousandths, then lap the piece= =20 against its partner to remove most tooling marks. You can also do a great j= ob=20 with a cleaning tank using kerosene and an air powered=C2=A0random orbital= =20 sander. Glue on some 320 wet or dry paper and sand the wear surface under a= =20 stream of Kerosene.
The little circles are great for holding oil. Once clean check for cra= cks.=20 =C2=A0=C2=A0=C2=A0=C2=A0
=C2=A0
And now into the weeds.......Many schemes have been tried in the pollu= tion=20 control area. Most involve exhaust gasses being loose inside the rotor hous= ings=20 where compressed air from an air pump was fed into the exhaust stream throu= gh=20 two steel nozzles that project into the exhaust port. This air came from a = port=20 in the center iron that is covered by the intake manifold. (In most every c= ase).=20 Those nozzles must be plugged.
The supply port in the center iron must be covered. The nozzles do not= fit=20 tight and may leak fresh air into the exhaust stream and supply a cracking = and=20 popping sound that confuses the tuner and Oxygen sensor.
=C2=A0
The center iron should match the coolant openings pattern of both roto= r=20 housings. On assembly add a thin coating of GE 100% silicone tub and tile= =20 sealant to the faces of the land areas that hold the "O" rings. W= orks great to=20 cure the tiny leaks and be sure to put it on the down legs clear to the pan= rail=20 to keep oil from seeping=C2=A0out when hot. I use the same GE silicone to s= eal=20 the exhaust flanges to the engine. Stays leak free until you pry off the ex= haust=20 system for service. If there is no gasket, it cannot fail. I have used a co= py of=20 the RX-2 RX-3 cooling system since 1980 Never an overheated engine. I can= =20 publish that drawing if anyone wants it.
=C2=A0
Set the side seal end clearance to zero, not .002" to 004" a= s seen in some=20 books. If both side seals and=C2=A0the gives you as close to advertised=20 compression as is possible. Quick starts even when hot. If the side seals a= nd=20 the corner seal pop back up after being compressed, then it is perfect. Goo= d to=20 9,600 RPM.
=C2=A0
More on bullet proof Rotaries as soon as I remember it.......The last = racer=20 is available and the spare (250 HP) engine is available.
=C2=A0
Lynn E. Hanover
=C2=A0
=C2=A0
=C2=A0
--047d7bdca50cb165ad053129cc9e--