Return-Path: Sender: (Marvin Kaye) To: lml@lancaironline.net Date: Mon, 19 Jul 2004 10:10:05 -0400 Message-ID: X-Original-Return-Path: Received: from core2.plantationcable.net ([12.163.4.19] verified) by logan.com (CommuniGate Pro SMTP 4.2b8) with SMTP id 324980 for lml@lancaironline.net; Sat, 17 Jul 2004 16:55:13 -0400 Received-SPF: error receiver=logan.com; client-ip=12.163.4.19; envelope-from=kloop@plantationcable.net Received: (qmail 29693 invoked from network); 17 Jul 2004 20:54:43 -0000 Received: from dhcp-12-163-7-176.plantationcable.net (HELO oemcomputer) (12.163.7.176) by core2.plantationcable.net with SMTP; 17 Jul 2004 20:54:43 -0000 X-Original-Message-ID: <000b01c46c40$06667060$b007a30c@oemcomputer> From: "George/Shirley Shattuck" X-Original-To: "OnLine Lancair" Subject: 320 hydraulics - 1989 kit X-Original-Date: Sat, 17 Jul 2004 16:52:51 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit 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 To anyone who has had this problem or knows of the solution: A couple months ago my hydraulic pump began cycling often, like every 15 to 20 seconds for a brief half second burst, in cruise at altitude, i.e. 85 or 9500 ft. It seemed to be altitude related, that is, the pump would begin cycling as I climbed above about 6000 ft. Previously, it would never cycle even over an hour or more leg. 1. I ordered from Lancair, and installed, a new dump/bypass valve. The symptoms/cycling continued. 2. I ordered and installed a new high pressure hydraulic switch. The pump cycling continued. There are no leaks, the reservoir is full. There has never been any cycling on the down side. Today, on another flight to get it to do something, it did something. At 9500 ft. in cruise, the short bursts of pump cycling got more frequent, then the pump started running for longer periods of time, then it came on and just continued running. I listened and watched and after about 20 to 30 seconds pulled the circuit breakers (pump and relays). The gear did not drop out of the wheelwells. I descended and prior to landing, put the gear switch down then pushed in the relay and pump CB's. The gear came down normally, three green, the pump turned off and did not cycle at all all the way in to shutdown. I'll get it up on jacks and try to sort it out. But in the meantime, can a hydraulic guru tell me if this problem is internal to the pump maybe? Do I need to replace the pump? If one of the actuator seals is shot the pump would cycle on the down side, right? Also, if an actuator seal is blown, the gear would fall out of the wheelwells with the CB's pulled, right? So, what is going on here? George Shattuck N320GS