Today's Message Index:
----------------------
1. 04:23 PM - High oil and fuel pressure (John Brunke)
2. 05:36 PM - Re: High oil and fuel pressure (Charles Heathco)
3. 07:44 PM - Re: High oil and fuel pressure (Kelly Patterson)
Message 1
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| Subject: | High oil and fuel pressure |
--> RV6-List message posted by: "John Brunke" <jwbrunk@attglobal.net>
Most of you folks are good at problem solving. I think I know the answer but here's
the situation.
Flew my RV-6 with an O-320 last week. Air temperature was 6 degrees F. Oil temp
never made it above 150 degrees. As I leveled off and the
fixed pitch prop rpm came up to normal cruise, the oil pressure came up to just
below or at red line and fluctuating about 2 to 3 psi. I reduced RPM to
1700 and slowly came back in to land and the pressure stayed around 85 psi (red
line is 90). In the pattern when my airspeed was back below
100 mph the oil pressure was in its normal range around 80psi.
Ok, it was a really cold day. So I'm thinking that the oil cooler was getting
too much air flow. I was able to block 1/2 of the air flow and flew a couple
of days later when it was in the high 30's. Flight went great.
Went flying today and the air temp was 23 degrees. Even with half the airflow
to the cooler blocked the pressure fluctuation up near red line occurred again.
This aircraft has Van's engine gauges and I was also venturing that the transducer
might be bad, but during these high oil pressure indications the fuel pressure
would also rise. They would rise at the same points. I'm concerned because redline
for fuel pressure is 8 psi and the indication at one point was 12 psi.
So, has anyone run into too much cooling for oil and if so did it also affect your
fuel pressure?
Also, I am concerned about the fuel pressure excursion above red line. What specifically
do you think I should check? I took the cowl off after today's flight
and did not notice any leaks.
The engine was about 45 degrees F when I started it. It is kept in a heated hanger
so the oil was not at ambient temperature when I started it.
I would appreciate your comments.
John Brunke
St. Charles, IL
Message 2
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| Subject: | Re: High oil and fuel pressure |
--> RV6-List message posted by: "Charles Heathco" <cheathco@comcast.net>
John, about the only thing I can think of that would raise fuel pressure
would be blocked tank vents, but you say it flucuated with oil pressure.
strange indeed. I am also on cherokee chat with O-320 problems discussed
regularly, I dont remember seeing your particualar problem come up. As for
oil cooling, mine never gets above 180- and when high and cold it stays
around 145-150. I have considered blocking some of air flow as you have but
have not yet done so.I will post your problem and see if can get something
for you. charlie heathco
----- Original Message -----
From: "John Brunke" <jwbrunk@attglobal.net>
Subject: RV6-List: High oil and fuel pressure
--> RV6-List message posted by: "John Brunke" <jwbrunk@attglobal.net>
Most of you folks are good at problem solving. I think I know the answer
but here's the situation.
Flew my RV-6 with an O-320 last week. Air temperature was 6 degrees F. Oil
temp never made it above 150 degrees. As I leveled off and the
fixed pitch prop rpm came up to normal cruise, the oil pressure came up to
just below or at red line and fluctuating about 2 to 3 psi. I reduced RPM
to
1700 and slowly came back in to land and the pressure stayed around 85 psi
(red line is 90). In the pattern when my airspeed was back below
100 mph the oil pressure was in its normal range around 80psi.
Ok, it was a really cold day. So I'm thinking that the oil cooler was
getting too much air flow. I was able to block 1/2 of the air flow and flew
a couple
of days later when it was in the high 30's. Flight went great.
Went flying today and the air temp was 23 degrees. Even with half the
airflow to the cooler blocked the pressure fluctuation up near red line
occurred again.
This aircraft has Van's engine gauges and I was also venturing that the
transducer might be bad, but during these high oil pressure indications the
fuel pressure
would also rise. They would rise at the same points. I'm concerned
because redline for fuel pressure is 8 psi and the indication at one point
was 12 psi.
So, has anyone run into too much cooling for oil and if so did it also
affect your fuel pressure?
Also, I am concerned about the fuel pressure excursion above red line. What
specifically do you think I should check? I took the cowl off after today's
flight
and did not notice any leaks.
The engine was about 45 degrees F when I started it. It is kept in a heated
hanger so the oil was not at ambient temperature when I started it.
I would appreciate your comments.
John Brunke
St. Charles, IL
Message 3
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| Subject: | High oil and fuel pressure |
--> RV6-List message posted by: "Kelly Patterson" <kbob@cox.net>
This is a WAG - but it may be a ground problem with the transducers. Is
your sender manifold the anodized type? The anodizing does not conduct
electricity. Since both the fuel and oil senders are mounted there, they
may be seeing the same problem at the same time. Try a star washer under
the manifold mount bolt. No idea why you would get so high on the fuel
pressure unless something is hairballed.
Kelly Patterson
PHX, AZ
>-----Original Message-----
>From: owner-rv6-list-server@matronics.com
>[mailto:owner-rv6-list-server@matronics.com] On Behalf Of John Brunke
>Sent: Thursday, January 27, 2005 5:23 PM
>To: rv6-list@matronics.com
>Subject: RV6-List: High oil and fuel pressure
>
>
>--> RV6-List message posted by: "John Brunke" <jwbrunk@attglobal.net>
>
>Most of you folks are good at problem solving. I think I know
>the answer but here's the situation.
>
>Flew my RV-6 with an O-320 last week. Air temperature was 6
>degrees F. Oil temp never made it above 150 degrees. As I
>leveled off and the fixed pitch prop rpm came up to normal
>cruise, the oil pressure came up to just below or at red line
>and fluctuating about 2 to 3 psi. I reduced RPM to
>1700 and slowly came back in to land and the pressure stayed
>around 85 psi (red line is 90). In the pattern when my
>airspeed was back below
>100 mph the oil pressure was in its normal range around 80psi.
>
>Ok, it was a really cold day. So I'm thinking that the oil
>cooler was getting too much air flow. I was able to block 1/2
>of the air flow and flew a couple of days later when it was in
>the high 30's. Flight went great.
>
>Went flying today and the air temp was 23 degrees. Even with
>half the airflow to the cooler blocked the pressure
>fluctuation up near red line occurred again.
>
>This aircraft has Van's engine gauges and I was also venturing
>that the transducer might be bad, but during these high oil
>pressure indications the fuel pressure
>would also rise. They would rise at the same points. I'm
>concerned because redline for fuel pressure is 8 psi and the
>indication at one point was 12 psi.
>
>So, has anyone run into too much cooling for oil and if so did
>it also affect your fuel pressure?
>
>Also, I am concerned about the fuel pressure excursion above
>red line. What specifically do you think I should check? I
>took the cowl off after today's flight and did not notice any leaks.
>
>The engine was about 45 degrees F when I started it. It is
>kept in a heated hanger so the oil was not at ambient
>temperature when I started it.
>
>I would appreciate your comments.
>
>John Brunke
>St. Charles, IL
>
>
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