Return-Path: Received: from [65.33.163.54] (account ) by logan.com (CommuniGate Pro WebUser 4.0.1) with HTTP id 1882684 for ; Wed, 20 Nov 2002 08:36:49 -0500 From: "Marvin Kaye" Subject: Re: [LML] Re: LNC2 Hydraulic Spool Valve in Backwards To: lml X-Mailer: CommuniGate Pro Web Mailer v.4.0.1 Date: Wed, 20 Nov 2002 08:36:49 -0500 Message-ID: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Christopher Zavatson" : Larry, Mike has deferred this one to me. We brought his pump to my hangar for a spool valve reversal about a year ago. His was the third pump I had come across with a reversed spool valve. Turning the spool valve around is something you can do provided you have an impact wrench. Use the attached JPG as a reference. Also, I always prefer to change out all the seals when opening up a pump. Although, when we did Mike's pump we reused all the old seals and it came out leak free. Seal kits can be obtained from Oildyne. The first step is to remove the two large hex plugs. This requires the torque wrench. These plugs are torqued to 50 ft-lb and there is no good way of supporting the pump body if trying to use a standard wrench or socket while applying this much torque. With the plugs removed a spring and poppet valve will fall out of each side. You will then see the check valve assembly in each hole. Through a hole at the base of the check valve you can see the spool valve. In order to get it out you must first remove the check valves. Use a punch or piece of heavy music wire inserted through the hole at the base of either check valve and push the spool valve against the opposite side check valve. Now use a hammer on the punch to push both the spool and check valve out. This will take some moderate force as the O-rings are very tight fitting. When the spool valve comes out you will see that it is not symmetric. The O-ring is off center and you can see the hole that allows the excess fluid to drain back to the reservoir. If memory serves me correctly the O-ring is supposed to be closest the high pressure port. Just in case, note the direction when it comes out. I like to push the second check valve out and check for burrs or any debris. I have in the past pulled burrs out of the spool valve area that had broken off and gotten trapped. Per Oildyne, use lots of petroleum jelly to lubricate the parts prior to reassembly in reverse order. Again, this will take some force as the O-rings are tight. I use various sized socket to help push the part in place. Hope this helps. Chris Zavatson N91CZ L360 std >>>Please tell me it's a no brainer to reverse it on my work bench. Would love to here the gory details. Spare no text as I am a bear of a wee little brain. <<< [The photo Chris sent along was pretty large so I've uploaded it to the LML website for access.... go to the bottom of the "Hydraulics.." page in the Attachments area to access it. I just didn't want to clog things up for the dial-up users out there. ]