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ACRO E-mail Archive Thread: Oil pressure problem (fwd)

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ACRO E-mail Archive Thread: Oil pressure problem (fwd)


Thread: Oil pressure problem (fwd)

Message: Oil pressure problem (fwd)

Follow-Up To: ACRO Email list (for List Members only)

From: dierks at

Date: Sat, 09 Sep 1995 01:20:46 UTC


   Guenther, please keep us posted as to what you find on this.

 I would open up the Christen valve and inspect the 'ball'
 and the seats as well as the spring.  Maybe something like
 the spring broke or with the ball getting hammered up and
 down it chipped the seat or the ball and this may allow it
 to suck air. 

 If your read the Christen valve information they say it
 is suppose to be flushed out each 50 hours to remove any
 sludge etc. from it.  Maybe something got trapped in it
 and is not letting the ball seat firmly on the seat.
 Cheers, Herman

> From root Tue Sep  5 12:28:01 1995
> Message-Id: <9509051705.AA08395 at>
> To: iac at
> Subject: Oil pressure problem
> Date: Tue, 05 Sep 1995 13:05:15 EDT
> From: "Dr. Guenther Eichhorn" <gei at>
> Sender: owner-iac at
> Precedence: bulk
> Hi,
> I have a problem that has my mechanic, Mattituck and Aviat
> baffled so far.  Maybe somebody on this list can help me:
> When my engine is at operating temperature, the oil pressure
> drops to below 50 psi.  It is not adjustable anymore with the
> oil pressure adjustment screw.
> The engine shows plenty of oil pressure when it is configured
> for regular oil circulation.  When I configure it for the
> inverted oil system, but do not use the Christen valve,
> instead connect the sump directly to the suction port to the
> pump, the oil pressure is lower than in the regular
> configuration, but satisfactory (~70psi and still adjustable).
> What have I done so far:
> 1. Complete engine teardown and repair at Mattituck.  
> 2. Checked all the gauges.
> 3. Replace the hoses to and from the Christen valve.
> 4. Replace the balls, etc in the Christen valve.
> Has anybody had a similar problem?  Does anybody know what it
> could be or what I could do to find out what the problem is. 
> We have tracked it down to a few parts (the inverted system),
> but we have no clue what causes the problem.
> Guenther
> | Guenther Eichhorn            |         `\   /'          |
> | CPL,ASMEL,ASES,IA,Glider,CFI |      ------^------       |
> | DC-3 type rating             |       |   |O|   |        |
> | AOPA, EAA, IAC, SSA          |      ------v------       |
> | Pitts S-2A: N1GE             |            |             |
> | gei at          |*** Flying is the Pitts **|
> | See also:   |


© Dr. Günther Eichhorn
Email Guenther Eichhorn