Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml@lancaironline.net
Date: Thu, 11 Mar 2004 09:00:20 -0500
Message-ID: <redirect-3073950@logan.com>
From: "Richard H. Helms" <rhhelms@cox.net>
Subject: Possible Gear Hydraulic System Vapor Lock
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit
Importance: Normal
In-Reply-To: <list-3073790@logan.com>


  I have over 500 hours on my 360 and have experienced what the tech rep
at Lancair believes it may be a vapor lock problem with the dump value.

   Flying with the gear up after a long and then short flight there was
no reaction to the gear switch being moved to the down position.  As
soon as pressure was released through the dump value the pump became
active.  I have replaced both the low pressure switch and the associated
gear relay with no change.
   Interestingly, when in the hanger trying to trouble shoot the source
of the problem, when cycling the gear up and moving the gear switch into
the down position before the gear reaches the full up position causes
the same symptoms to occur:  nothing happens.  Moving the dump valve
brings the pump alive and the gear down.  If the gear is allowed to go
all the way up and stop and the gear switch is moved to the down
position it will function normally when the switch is moved into the
down position (Except of course when I am flying.  I cannot otherwise
seem to duplicate the flying symptoms in the hanger.
   My next troubleshooting step is to replace the dump value but my
suspicion is that it is in the pump itself.
   Has anyone had this problem?

Hollis Helms
Oak Hill, VA