X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 07 Feb 2008 00:38:54 -0500 Message-ID: X-Original-Return-Path: Received: from bay0-omc1-s1.bay0.hotmail.com ([65.54.246.73] verified) by logan.com (CommuniGate Pro SMTP 5.2.0) with ESMTP id 2718608 for lml@lancaironline.net; Wed, 06 Feb 2008 21:26:10 -0500 Received-SPF: pass receiver=logan.com; client-ip=65.54.246.73; envelope-from=randystuart@hotmail.com Received: from hotmail.com ([65.55.139.22]) by bay0-omc1-s1.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 6 Feb 2008 18:25:31 -0800 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Wed, 6 Feb 2008 18:25:31 -0800 X-Original-Message-ID: Received: from 68.183.63.181 by BAY134-DAV12.phx.gbl with DAV; Thu, 07 Feb 2008 02:25:29 +0000 X-Originating-IP: [68.183.63.181] X-Originating-Email: [randystuart@hotmail.com] X-Sender: randystuart@hotmail.com From: "Randy" X-Original-To: "Lancair Mailing List" References: Subject: Re: [LML] 235/320/360 gear dump valve idea X-Original-Date: Wed, 6 Feb 2008 18:25:25 -0800 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00D7_01C868ED.A4A7D720" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 X-OriginalArrivalTime: 07 Feb 2008 02:25:31.0460 (UTC) FILETIME=[B61A9040:01C86930] X-Original-Return-Path: randystuart@hotmail.com This is a multi-part message in MIME format. ------=_NextPart_000_00D7_01C868ED.A4A7D720 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable This can be done very easy with a simple T-shuttle valve. I got one but = haven't felt like putting the pump out yet. The problem is that when = the pump stops the shuttle valve, in the pump, closes. This stops the = fluid from retuning to the reservoir when it expands from the heat. By = adding a small T-shuttle valve in the low side (down) of the system, it = would return the fluid to the reservoir automatically. The low side of = the pump connects to one side of the T (Top), drill a hole in the = reservoir and connect the other side of the T (Top) to the reservoir, = the bottom of the T goes to the actuators (down side ). Now when you run = the gear down is closes the T-shuttle valve and flows the fluid to the = down actuators. when the gear runs up, the fluid from the down side = flows back through the pumps shuttle valve until it closes. When the = fluid expands and the pump valve is closed the T-shuttle valve opens and = flows the small amount of fluid back into the reservoir.=20 I haven't had a chance to connect this up to my pump and it might take a = little adjusting to get it to work just right but this should completely = solve the "No gear down" problem on hot days. And do the job in the = background with no buttons or extra levers, etc.=20 Randy Stuart LNC2 ----- Original Message -----=20 From: randy snarr=20 To: lml@lancaironline.net=20 Sent: Wednesday, February 06, 2008 9:28 AM Subject: [LML] 235/320/360 gear dump valve idea I have been thinking about this for some time. With the way the hydraulic system is currently designed, you equalize = the pressure on the high and low sides when it is opened. For those of = us who have pressure gauges, you can see that you can have significant = pressure on the system even when the valve is opened. I want to be able = to not only equalize the pressure between the high and low sides of the = hydraulic system with the dump valve but also release the pressure on = both sides. Today I purchased a 3 way valve to do just that. The idea is to open = the valve connecting the high and low sides and also releasing the = pressure back to the tank. I will most likely run a low pressure line like nylaflow back to the = pump and make spin up a custom fitting on the lathe out of aluminum to = go into the dipstick hole and terminate the return line there. I will = make a needle dipstick checker that will screw into the same fitting for = checking fluid level. If you wanted to do it the easy way, you could always just dump the = low pressure line out the belly of the airplane onto the ground. It = would take very little fluid to drop the pressure and there would be no = need to deal with connecting the low pressure fluid line to the tank. I hate pulling the airplane out of a cool hanger into the warm = sunshine and watching the gear pressures rise to 6-700 lbs before the = master switch is turned on! We all know what happens when they hit 900. = Yep no gear retraction as the upper limit has been tripped by the system = pressure.=20 My new valve would fix that!!! I hope... Chris Z and others who are much smarter than me please chime in with = your input.... Am I missing something??? Thanks!!! Randy L. Snarr N694RS 235/320 Salt Lake City, Utah -------------------------------------------------------------------------= ----- Never miss a thing. Make Yahoo your homepage. ------=_NextPart_000_00D7_01C868ED.A4A7D720 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
This can be done = very easy=20 with a simple T-shuttle valve. I got one but haven't felt like putting = the pump=20 out yet.  The problem is that when the pump stops the shuttle = valve, in the=20 pump, closes. This stops the fluid from retuning to the reservoir = when it=20 expands from the heat. By adding a small T-shuttle valve in the low side = (down)=20 of the system, it would return the fluid to the reservoir automatically. = The low=20 side of the pump connects to one side of the T (Top), drill a hole in = the=20 reservoir and connect the other side of the T (Top) to the reservoir, = the bottom=20 of the T goes to the actuators (down side ). Now when you run the gear = down is=20 closes the T-shuttle valve and flows the fluid to the down actuators. = when the=20 gear runs up, the fluid from the down side flows back through the pumps = shuttle=20 valve until it closes. When the fluid expands and the pump valve is = closed the=20 T-shuttle valve opens and flows the small amount of fluid back into the=20 reservoir.
I haven't had a = chance to=20 connect this up to my pump and it might take a little adjusting to get = it to=20 work just right but this should completely solve the "No gear down" = problem on=20 hot days. And do the job in the background with no buttons or extra = levers, etc.=20
 
Randy=20 Stuart
LNC2
----- Original Message -----
From:=20 randy=20 snarr
Sent: Wednesday, February 06, = 2008 9:28=20 AM
Subject: [LML] 235/320/360 gear = dump=20 valve idea

I have been thinking about this for some = time.

With the=20 way the hydraulic system is currently designed, you equalize the = pressure on=20 the high and low sides when it is opened. For those of us who have = pressure=20 gauges, you can see that you can have significant pressure on the = system even=20 when the valve is opened. I want to be able to not only equalize the = pressure=20 between the high and low sides of the hydraulic system with the dump = valve but=20 also release the pressure on both sides.

Today I purchased a 3 = way=20 valve to do just that. The idea  is to open the valve =20 connecting  the high and low sides and also releasing the = pressure back=20 to the tank.
I will most likely run a low pressure line like = nylaflow back=20 to the pump and make spin up a custom fitting on the lathe out of = aluminum to=20 go into the dipstick hole and terminate the return line there. I will = make a=20 needle dipstick checker that will screw into the same fitting for = checking=20 fluid level.
If you wanted to do it the easy way, you could always = just=20 dump the low pressure line out the belly of the airplane onto the = ground. It=20 would take very little fluid to drop the pressure and there would be = no need=20 to deal with connecting the low pressure fluid line to the = tank.

I hate=20 pulling the airplane out of a cool hanger into the warm sunshine and = watching=20 the gear pressures rise to 6-700 lbs before the master switch is = turned on! We=20 all know what happens when they hit 900. Yep no gear retraction as the = upper=20 limit has been tripped by the system pressure.
My new valve would = fix=20 that!!!
I hope...

Chris Z and others who are much smarter = than me=20 please chime in with your input....
Am I missing=20 something???

Thanks!!!

Randy L. Snarr
N694RS = 235/320
Salt=20 Lake City, Utah

Never miss a thing. Ma= ke Yahoo=20 your homepage. ------=_NextPart_000_00D7_01C868ED.A4A7D720--