X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from web83905.mail.sp1.yahoo.com ([69.147.92.105] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with SMTP id 3836258 for flyrotary@lancaironline.net; Fri, 04 Sep 2009 09:17:57 -0400 Received-SPF: none receiver=logan.com; client-ip=69.147.92.105; envelope-from=delta11xd@att.net Received: (qmail 76092 invoked by uid 60001); 4 Sep 2009 13:17:21 -0000 Message-ID: <670953.76069.qm@web83905.mail.sp1.yahoo.com> X-YMail-OSG: 70fIjFQVM1nS_HB_l6Qx1gGrK3GBC0fmsM4uCEa4EXHe.Qgbb0YnNZtN Received: from [76.230.154.33] by web83905.mail.sp1.yahoo.com via HTTP; Fri, 04 Sep 2009 06:17:20 PDT X-Mailer: YahooMailClassic/6.1.2 YahooMailWebService/0.7.338.2 Date: Fri, 4 Sep 2009 06:17:20 -0700 (PDT) From: James Maher Subject: Re: [FlyRotary] Re: Help for John Slade To: Rotary motors in aircraft In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-1362215612-1252070240=:76069" --0-1362215612-1252070240=:76069 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable John, Thanks for your very detailed report on your fuel filter clogging incident. A few years ago I had a very similar incident when I was 18 miles out from = the airport during my 4th test flight. After some=A0slow flight testing I went to throttle up and the engine did n= ot want to cooperate. I switched pumps and it got worst. It was running very lean (off the bottom= of the A/F gage). Needless to say I made it back to the airport running at about 50% power an= d very lean. I knew I had one shot at landing, as I did not have sufficient power for a = go around. The pucker factor was high. What I found, upon inspection, was that the gascolator had a clear jello li= ke substance on the screen and the single in-line K&N billet filter stainle= ss mesh screen was completely clogged. ( I've since changed to 2 filters) Luckily this type of filter has a by-pass function, if it gets clogged, and= allows some fuel to flow even when completely clogged. That featue saved my bacon. You may have been running on one rotor due to injector clogging. You may want to flow test the injectors to be sure that their internal scre= ens are not clogged. My fuel tank was fiberglass with Aeropoxy which apparently does not hold up= to ethanol. I've since switched to a vinyl ester tank. =A0 =A0 Jim Dyke Delta N11XD --- On Thu, 9/3/09, John Slade wrote: From: John Slade Subject: [FlyRotary] Re: Help for John Slade To: "Rotary motors in aircraft" Date: Thursday, September 3, 2009, 10:26 PM First of all, thanks to the many people who responded to Buly's message.=A0= I'm sorry I wasn't able to call everyone back. I was on the phone for a co= uple of hours with various helpers, but failed to explain to all of them th= at I was an idiot. In my own defense it had been a very long day. With regard to mogas, epoxy tanks and filters, let me try to clear up any m= isunderstandings and provide whatever information I can to assist others av= oid the same issues.... Yes. My MGS 335 built tanks failed to hold up to ethanol in mogas. The symp= toms of failure are (or were in my case) fairly benign. After about 4 years there was evidence of softening of= the inner strake skin. This first showed up as faint lines along the curve= of the strakes where we bend the skin. There were no leaks or "gummy stuff= " found in the fuel or filters. At about 5 years, reaching through the fill= er holes to squeeze the inner skin proved that the inner skin has significa= ntly softened. I decided tht the tanks needed to be rebuilt. I removed the = strake tops and discovered that the entire inner skin was soft. Interesting= ly, in the areas where there were 2 BID tapes the tapes were soft, but the = skin under them was undamaged - it seemed to me that the ethanol had weaken= ed the skin very gradually, and had just about got through two layers. A le= ak was clearly imminent. To cut a long story short, I removed the bulkheads and removed the inner sk= in down to foam. I then rebuilt the strakes from the inside with plans layu= ps using EZ-poxy and built and installed new bulkheads. When this was all c= ured I constructed inner tanks in each of the three sections of each strake= using vinyl ester resin and 1 UNI. These inner tanks have lids which were = added to the underside of the strake tops prior to re installation. Perhaps= the inner tanks may be superfluous based on others experience with EX-Poxy= (Perry Mick, for example). I just didn't want to do this (roughly 80 hrs) = job again so a I used a "belt and braces" approach. The strake "lids" were reinstalled and taped. Last week I completed the ref= inishing of the strake tops filled the tanks, taxi tested, and cleaned the = filters. There was very little crud in the filters. I then test flew the ai= rplane for 1.5 hrs and cleaned the filters again prior to my planned cross = country flight from Rhode Island to Florida. I made a fuel stop for mogas a= t SFQ in VA, then topped up again at BNL in SC. On my first use of the righ= t tank after the BNL fillup The engine immediately ran rough at reduced rpm= . Switching off the right tank did not rectify the situation. (each tank ha= s a separate pump & filter. The feed is T'd at the rail and I always switch= both on, then switch off the one I'm moving from). This means that the eng= ine was never running on just right tank. Theoretically it should have been= getting fuel from the left. Apparently it was not. The engine ran rough at around 3500 rpm max throttle from then until touchd= own at 17FL. Switching fuel pumps and injectors had no effect. I'll cover t= he emergency landing in another post. After landing I turned to back-taxi o= n the 7500' runway and found that the engine ran perfectly. I suspected fil= ter blockage, but was puzzled as to why running on left tank did not solve = the problem. On inspecting the filters I found the left one to be clean, an= d the right one completely blocked with about a cubic MM of epoxy dust mate= rial. Failure of the engine to start after filer cleaning was simply my err= or in forgetting to switch the manual tank isolation valve. Once I switched= this valve the engine started and ran as normal on the last leg from 17FL = to LNA. My guess is that the pressure surge from initializing the right pump cause = some epoxy dust to be forced through the (post pump) Earls stainless filter= and on to the injectors' screens. This is the only way that the left pump = would have failed to correct the problem. As for the sudden "arrival" of th= e crud after finding clean filters twice - Here's my theory, for what it's = worth - When at the hangar I fill the tanks from 5 gal fuel containers. At = SFQ and BNL I used the airport pumps. These pumps are VERY high volume / hi= gh pressure. You can fill a Cozy tank in just a few seconds. I think that t= he high volume fuel insertion caused turbulence in the tanks that hadn't oc= curred with my normal filling method, and forced crud out of the corners in= to the sumps. Anyway, thanks for all the good wishes. I'm safe & sound back in South Flor= ida, and apart from this inconvenient little incident, the engine purred li= ke a kitten the entire way. John Slade Turbo Rotary Cozy N96PM -- Homepage:=A0 http://www.flyrotary.com/ Archive and UnSub:=A0=A0=A0http://mail.lancaironline.net:81/lists/flyrotary= /List.html --0-1362215612-1252070240=:76069 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
John,
Thanks for your very detailed report on your fuel filter clogging inci= dent.
A few years ago I had a very similar incident when I was 18 miles out = from the airport
during my 4th test flight.
After some slow flight testing I went to throttle up and the engi= ne did not want to cooperate.
I switched pumps and it got worst. It was running very lean (off the b= ottom of the A/F gage).
Needless to say I made it back to the airport running at about 50% pow= er and very lean.
I knew I had one shot at landing, as I did not have sufficient power f= or a go around.
The pucker factor was high.
What I found, upon inspection, was that the gascolator had a clear jel= lo like substance on the screen and the single in-line K&N billet filte= r stainless mesh screen was completely clogged. ( I've since changed to 2 f= ilters)
Luckily this type of filter has a by-pass function, if it gets clogged= , and allows some fuel to
flow even when completely clogged. That featue saved my bacon.
You may have been running on one rotor due to injector clogging.
You may want to flow test the injectors to be sure that their internal= screens are not clogged.
My fuel tank was fiberglass with Aeropoxy which apparently does not ho= ld up to ethanol.
I've since switched to a vinyl ester tank.
 
 
Jim
Dyke Delta N11XD


--- On Thu, 9/3/09, John Slade <jslade@canardaviation= .com> wrote:

From: John Slade <jslade@canardaviation.com>= ;
Subject: [FlyRotary] Re: Help for John Slade
To: "Rotary motors in = aircraft" <flyrotary@lancaironline.net>
Date: Thursday, September = 3, 2009, 10:26 PM

First of all, thanks to the many people who responde= d to Buly's message.  I'm sorry I wasn't able to call everyone back. I= was on the phone for a couple of hours with various helpers, but failed to= explain to all of them that I was an idiot. In my own defense it had been = a very long day.

With regard to mogas, epoxy tanks and filters, let = me try to clear up any misunderstandings and provide whatever information I= can to assist others avoid the same issues....

Yes. My MGS 335 buil= t tanks failed to hold up to ethanol in mogas. The symptoms of failure are = (or were in my
case) fairly benign. After about 4 years there was eviden= ce of softening of the inner strake skin. This first showed up as faint lin= es along the curve of the strakes where we bend the skin. There were no lea= ks or "gummy stuff" found in the fuel or filters. At about 5 years, reachin= g through the filler holes to squeeze the inner skin proved that the inner skin has significantly softened. I decided tht the tanks needed to b= e rebuilt. I removed the strake tops and discovered that the entire inner s= kin was soft. Interestingly, in the areas where there were 2 BID tapes the = tapes were soft, but the skin under them was undamaged - it seemed to me th= at the ethanol had weakened the skin very gradually, and had just about got= through two layers. A leak was clearly imminent.

To cut a long stor= y short, I removed the bulkheads and removed the inner skin down to foam. I= then rebuilt the strakes from the inside with plans layups using EZ-poxy a= nd built and installed new bulkheads. When this was all cured I constructed= inner tanks in each of the three sections of each strake using vinyl ester= resin and 1 UNI. These inner tanks have lids which were added to the under= side of the strake tops prior to re installation. Perhaps the inner tanks m= ay be superfluous based on others experience with EX-Poxy (Perry Mick, for example). I just didn't want to do this (roughly 80 hrs) job aga= in so a I used a "belt and braces" approach.

The strake "lids" were = reinstalled and taped. Last week I completed the refinishing of the strake = tops filled the tanks, taxi tested, and cleaned the filters. There was very= little crud in the filters. I then test flew the airplane for 1.5 hrs and = cleaned the filters again prior to my planned cross country flight from Rho= de Island to Florida. I made a fuel stop for mogas at SFQ in VA, then toppe= d up again at BNL in SC. On my first use of the right tank after the BNL fi= llup The engine immediately ran rough at reduced rpm. Switching off the rig= ht tank did not rectify the situation. (each tank has a separate pump &= filter. The feed is T'd at the rail and I always switch both on, then swit= ch off the one I'm moving from). This means that the engine was never runni= ng on just right tank. Theoretically it should have been getting fuel from the left. Apparently it was not.

The engine ran rough at = around 3500 rpm max throttle from then until touchdown at 17FL. Switching f= uel pumps and injectors had no effect. I'll cover the emergency landing in = another post. After landing I turned to back-taxi on the 7500' runway and f= ound that the engine ran perfectly. I suspected filter blockage, but was pu= zzled as to why running on left tank did not solve the problem. On inspecti= ng the filters I found the left one to be clean, and the right one complete= ly blocked with about a cubic MM of epoxy dust material. Failure of the eng= ine to start after filer cleaning was simply my error in forgetting to swit= ch the manual tank isolation valve. Once I switched this valve the engine s= tarted and ran as normal on the last leg from 17FL to LNA.

My guess = is that the pressure surge from initializing the right pump cause some epox= y dust to be forced through the (post pump) Earls stainless filter and on to the injectors' screens. This is the only way that the left pump = would have failed to correct the problem. As for the sudden "arrival" of th= e crud after finding clean filters twice - Here's my theory, for what it's = worth - When at the hangar I fill the tanks from 5 gal fuel containers. At = SFQ and BNL I used the airport pumps. These pumps are VERY high volume / hi= gh pressure. You can fill a Cozy tank in just a few seconds. I think that t= he high volume fuel insertion caused turbulence in the tanks that hadn't oc= curred with my normal filling method, and forced crud out of the corners in= to the sumps.

Anyway, thanks for all the good wishes. I'm safe &= sound back in South Florida, and apart from this inconvenient little incid= ent, the engine purred like a kitten the entire way.

John Slade
T= urbo Rotary Cozy N96PM


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