Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.2b2) with ESMTP id 3186550 for flyrotary@lancaironline.net; Fri, 23 Apr 2004 11:42:49 -0400 Received: from EDWARD (clt25-78-058.carolina.rr.com [24.25.78.58]) by ms-smtp-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i3NFgkC9001243 for ; Fri, 23 Apr 2004 11:42:47 -0400 (EDT) Message-ID: <001e01c42949$a2939970$2402a8c0@EDWARD> From: "Ed Anderson" To: "Rotary motors in aircraft" Subject: Alternator Problem Date: Fri, 23 Apr 2004 11:42:50 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001B_01C42928.1B48C100" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1409 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_001B_01C42928.1B48C100 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Went out to the aircraft this morning to check out the alternator = problem I encountered returning from Sun & Fun. The symptoms were lower = than normal alternator voltage (13.8 vice nominal 14.8) and field coil = circuit breaker popping three times. It appears that the cause was insufficient tension on the belts. I = drive the alternator with two belts which also wrap around the water = pump. I reached in an grabbed the pulley hub of the water pump and = could easily turn it against the belt tension. My alternator is = undedriven by approx 40%, so any further reduction is speed (due to = slipping belts) apparently is just too little pulley speed. =20 My voltage guardian pops the circuit breaker whenever it encounters = either an overvoltage or undervoltage condition. I have the = undervoltage limit set at 13.8 volts which was at the border line of = what the alternator was producing. So apparently the voltage dropped = below that on occasion and that apparently resulted in the popped CK. Tightened up the belts and voltage was back to 14.6 and battery up to = 12.8 volts, so all appears to be well. Glad it was that easy. Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ------=_NextPart_000_001B_01C42928.1B48C100 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Went out to the aircraft this morning = to check out=20 the alternator problem I encountered returning from Sun & Fun.  = The=20 symptoms were lower than normal alternator voltage (13.8 vice nominal = 14.8) and=20 field coil circuit breaker popping three times.
 
It appears that the cause was = insufficient tension=20 on the belts.  I drive the alternator with two belts which also = wrap around=20 the water pump.  I reached in an grabbed the pulley hub of the = water pump=20 and could easily turn it against the belt tension.  My alternator = is=20 undedriven by approx 40%, so any further reduction is speed (due to = slipping=20 belts) apparently is just too little pulley speed. 
 
My voltage guardian pops the circuit = breaker=20 whenever it encounters either an overvoltage or undervoltage = condition.  I=20 have the undervoltage limit set at 13.8 volts which was at the border = line of=20 what the alternator was producing.  So apparently the voltage = dropped=20 below that on occasion and that apparently resulted in the popped=20 CK.
 
Tightened up the belts and voltage was = back to 14.6=20 and battery up to 12.8 volts, so all appears to be well.  Glad it = was that=20 easy.
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary=20 Powered
Matthews, NC
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