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Understood . . . but a module like mine doesn't
care what version your pump is, it just works.
Wolfgang
----- Original Message -----
Sent: Sunday, January 27, 2013 6:59
AM
Subject: Re: [LML] Re: Thermal influence
on Hydraulic Pressure
Charley,
Lancair started adding return springs inside the spool valve for
Legacy pumps in about 2005. One of the consequences of doing this is what you have observed in the
hangar. You sort of have a 'get out of jail free' card in that your
hydraulic system has a three-way valve. It doesn't prevent the
lock-up. It just gives you a way out. Folks installing the
'Legacy' pump in 300 series plane with a two-way valve can get stuck.
Fortunately the springs are easily removed and Parker has been providing the
parts free-of-charge to reset pumps back to the pre-2005 configuration.
Chris
Chris Zavatson
N91CZ
360std. 1,400 hrs
From: Charles Brown
<browncc1@verizon.net>
To: lml@lancaironline.net
Sent: Friday, January 25, 2013 11:07
PM
Subject: [LML] Re: Thermal
influence on Hydraulic Pressure
This has happened to me even at the beginning of a flight, if the temps
in the hangar have gone from cold on a previous day, to warm on flight day.
I guess cold temps shrink the fluid and suck more from the reservoir
into the lines, and when it warms, the pressure builds on both sides of the
system, so that the "up" and "down" pressure switches are both open and the
gear won't move until I pop the bleed valve.
Nasty when the gear won't retract just after blasting off into a low
overcast.
Charley Brown
Legacy #299 200 hr
On Jan 25, 2013, at 7:23 AM, randy snarr wrote:
.
I dont like having to open the dump
valve but it is necessary once in a while especially when it is cold. The
pressures on both sides of the system climb due to the engine heat and the
gear sometimes will not move without dumping the pressure.
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