X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 25 May 2008 08:23:52 -0400 Message-ID: X-Original-Return-Path: Received: from n24.bullet.mail.mud.yahoo.com ([68.142.206.163] verified) by logan.com (CommuniGate Pro SMTP 5.2.3) with SMTP id 2937143 for lml@lancaironline.net; Sat, 24 May 2008 15:35:15 -0400 Received: from [68.142.200.227] by n24.bullet.mail.mud.yahoo.com with NNFMP; 24 May 2008 19:34:57 -0000 Received: from [68.142.201.245] by t8.bullet.mud.yahoo.com with NNFMP; 24 May 2008 19:35:01 -0000 Received: from [127.0.0.1] by omp406.mail.mud.yahoo.com with NNFMP; 24 May 2008 19:35:01 -0000 X-Yahoo-Newman-Id: 954566.99586.bm@omp406.mail.mud.yahoo.com Received: (qmail 90253 invoked from network); 24 May 2008 19:35:01 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:X-Mailer:Thread-Index:Content-Language; b=t1HfbKI6ARoVxulHQ3qifz7XOYo0jlLDw/C0iR5jmFhlUr60St80/cFN6oSjIon5Uwu/Kfnx0hEXBD68RQ2tfMuygg7ABIeTNG0ewxEXnMklazZqYtpRVyEHZ+tisyHt77X1t8kAdhGAaQj/7vgwvcm9/nph795zWTUY56pYRFY= ; Received: from unknown (HELO Laptop) (mcmess1919@72.177.79.141 with login) by smtp119.plus.mail.mud.yahoo.com with SMTP; 24 May 2008 19:35:01 -0000 X-YMail-OSG: ZjPKulUVM1niKRRdfJ5azIMaU2Smi36JhXwPCE5obqi1U1qRhSSrqOM5tSY0F3wjX9yEYMNM9yJRbs8u9xZs6xuftu5F1zwJ5H_FfcIhPSBCYliOeFHrtIVnEV3LOord1vc- X-Yahoo-Newman-Property: ymail-3 From: "Steve Colwell" X-Original-To: "'Lancair Mailing List'" Subject: Crankcase pressure=OIL ON BELLY X-Original-Date: Sat, 24 May 2008 14:35:00 -0500 X-Original-Message-ID: <000001c8bdd5$4302cd80$c9086880$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C8BDAB.5A2CC580" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: Aci91UB1I4pv6l2mSJCguMJmPskMlA== Content-Language: en-us This is a multipart message in MIME format. ------=_NextPart_000_0001_01C8BDAB.5A2CC580 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable My Cont. IO-550 (normally aspirated, stock comp ratio) is blowing = enough oil from the crankcase breather to put a thick coat on =BD of the = belly, halfway to the tail in 10 min. of flying. Originally I thought I had overfilled the 8 qt. crankcase so I drained the oil, changed the filter = and refilled with 6.5 qts. During runup and takeoff roll the manometer = (tapped into the crankcase vent about the mid-point of its length) will read = zero until plane has about 120 knots indicated airspeed. At 120 to 200 knots = the manometer reads 4=94 to 5=94 with a short spike up to 14=94 to 20=94 = when power is reduced in the pattern. The following tests have been run: =20 Compression test: high 60=92s to low 70=92s which I am told is normal = for Continentals, oil is normal color (not black, which would indicate = blow-by) =20 Washed engine with mineral spirits to see if any fresh oil was = appearing. =20 =20 Upper plugs are normal color, maybe a dark tan insulator, no fouling problems =20 Low pressure on crankcase with 12=94 balloon on crankcase vent: takes = about 3 min to deflate, tried soap suds around all accessible seals, dipstick = cap, mags, pushrod tubes, etc.. =20 Relocated crankcase vent to right side cowl outlet =20 Cut a anti-siphon hole 6=94 above the end of the vent tube on normal = left side exit. =20 Taped the dipstick cap with aluminum tape. =20 Put 20 psi air pressure on crankcase, soap suds again, air going past = piston rings, tried turning prop with no noticeable difference from cyl to cyl. =20 Replaced crankshaft seal. =20 Anything that required a flight test would deposit the same thick coat = of oil on the belly in a single trip around the pattern. I have just = about run out of ideas, the engine builder has never heard of anything like = this and the cylinder supplier could only suggest it could be the crankshaft seal. It could be a leaking seal in the alternators or mags or ???? = I need help. =20 Steve Colwell Legacy 916 505-6099 =20 =20 =20 =20 ------=_NextPart_000_0001_01C8BDAB.5A2CC580 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

My Cont. IO-550 (normally aspirated, stock comp = ratio)=A0 is blowing enough oil from the crankcase breather to put a thick coat on=A0 = =BD of the belly, halfway to the tail in 10 min. of flying.=A0 Originally I thought = I had overfilled the 8 qt. crankcase so I drained the oil, changed the filter = and refilled with 6.5 qts.=A0 During runup and takeoff roll the manometer = (tapped into the crankcase vent about the mid-point of its length) will read = zero until plane has about 120 knots indicated airspeed.=A0 At 120 to 200 knots the manometer reads 4” to 5” with a short spike up to 14” = to 20” when power is reduced in the pattern.=A0 The following tests = have been run:

 

Compression test:=A0 high 60’s to low = 70’s which I am told is normal for Continentals, oil is normal color (not black, = which would indicate blow-by)

 

Washed engine with mineral spirits to see if any = fresh oil was appearing.=A0

 

Upper plugs are normal color, maybe a dark tan = insulator, no fouling problems

 

Low pressure on crankcase with 12” balloon on crankcase vent:=A0 takes about 3 min to deflate, tried soap suds around = all accessible seals, dipstick cap, mags, pushrod tubes, = etc..

 

Relocated crankcase vent to right side cowl = outlet

 

Cut a anti-siphon hole 6” above the end of = the vent tube on normal left side exit.

 

Taped the dipstick cap with aluminum = tape.

 

Put 20 psi air pressure on crankcase, soap suds = again, air going past piston rings, tried turning prop with no noticeable = difference from cyl to cyl.

 

Replaced crankshaft seal.

 

Anything that required a flight test would deposit = the same thick coat of oil on the belly in a single trip around the = pattern.=A0=A0 I have just about run out of ideas, the engine builder has never heard of = anything like this and the cylinder supplier could only suggest it could be the crankshaft seal.=A0=A0 It could be a leaking seal in the alternators or = mags or ????=A0=A0=A0 I need help.

 

Steve Colwell=A0 Legacy=A0=A0 916 = 505-6099

 

 

 

 

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