high oil pressure????

[SupraPilot]

hello,
Some of you may have read my other thread on here about new engine break in....we are still doing this as per what the mechanics told us and it pretty much goes along with what everyone says on here...sometimes it hard to follow exactly becasue of weather or traffic ect ect while flying...but for the most part we folow the procedure exactly...

so the other day we went for another quick hr long flight to put some more break in hours on the engine..i checked the oil (which was very clean to the point that it was hard to see on the dipstick exaclty where it was) and it showed just about 8 qts... i know the manual says anything between 6-8 qts is ok...
so we started the plane and off we went..it was pretty cold out so i noted that the oil pressure was fairly high...we took our time taxiing and all that to let the oil get a little warmer...and then we took off..we flew to another airport about 30 mins away and got some fuel...we then took off again and headed home...i noticed on the TO roll the pressure was still fairly high but not over redline...shortly after TO and into our cruise i noticed the oil pressure was just over the redline so i backed off the throttle slightly and i got it stabilized at just a tad under the redline...the engine ddint run bad or anything, but this got me very concerned while flying..
so does anyone know if this is normal for it to be this high maybe becasue of the different type of oil for break in or something??

I know when i used to rent, the FBO told us all to make sure there wasnt anything more then 7 qts in the planes when they are cold becasue one person had filled it up to 8 qts and the engine's seals all started to leak..

just want to make sure we dont have too much oil in the plane or if this is perfectly normal for there to be higher then normal oil pressures on a new engine..

thanks in advance

Ant

 

[Tom-D]

hello,
Some of you may have read my other thread on here about new engine break in....we are still doing this as per what the mechanics told us and it pretty much goes along with what everyone says on here...sometimes it hard to follow exactly becasue of weather or traffic ect ect while flying...but for the most part we folow the procedure exactly...

so the other day we went for another quick hr long flight to put some more break in hours on the engine..i checked the oil (which was very clean to the point that it was hard to see on the dipstick exaclty where it was) and it showed just about 8 qts... i know the manual says anything between 6-8 qts is ok...
so we started the plane and off we went..it was pretty cold out so i noted that the oil pressure was fairly high...we took our time taxiing and all that to let the oil get a little warmer...and then we took off..we flew to another airport about 30 mins away and got some fuel...we then took off again and headed home...i noticed on the TO roll the pressure was still fairly high but not over redline...shortly after TO and into our cruise i noticed the oil pressure was just over the redline so i backed off the throttle slightly and i got it stabilized at just a tad under the redline...the engine ddint run bad or anything, but this got me very concerned while flying..
so does anyone know if this is normal for it to be this high maybe becasue of the different type of oil for break in or something??

I know when i used to rent, the FBO told us all to make sure there wasnt anything more then 7 qts in the planes when they are cold becasue one person had filled it up to 8 qts and the engine's seals all started to leak..

just want to make sure we dont have too much oil in the plane or if this is perfectly normal for there to be higher then normal oil pressures on a new engine..

thanks in advance

Ant

oil quanity has nothing to do with oil pressure until there is none,

I would suspect the when the engine was overhauled the washer some one placed behine the oil pressure relief valve spring to make more oil pressure with old bearings, was not removed.

 

[bsdunek]

NC19143 is probably right on the washer, and is correct on the quantity - it makes no difference on the pressure until it's too low.
You don't mention what the outside temp was. Oil pressure can be higher when it's cold as the oil is thicker. Still, it shouldn't go over red line. Better get it checked! B)

 

[SupraPilot]

Yeah the outide temp was pretty cold.maybe 30-35 degrees...the plane is kept in a hangar but we didnt plug in the block heater..but i would say the ambient temps in the hangar when we got to the airport was about 45 degrees..so its not like it was frigid temps or anything well below freezing or anything...but when i saw the high pressure we had already flown the plane about 45 mins before we fueled up, and took off again, so the oil was already at operating temps..i ddint see high oil pressures on the first takeoff when the oil temps werent all the way to operating temps.

I build high performance cars so ive seen high oil pressures from higher then normal oil levels..even at very high temps when the oil can be like water..and this condition can blow seals or cause them to leak...maybe its diff for cars since they are consistently at alot higher rpms then airplanes, but when i used to rent a cherokee 160 they told me to never fill up to 8 qts of oil becasue some renters used to do this and it casue all the seals on the engine to leak...

when i was flying i was trying to look behind me to make sure i wasn't leaving a trail of burning oil smoke from leaking seals when i saw the pressure up over the redline..

so what about this washer you guys are talking about?? is it a normal thing to happen or did the mechanic screw up? and how easy is it to fix??

also the plane is a piper warrior with 160 hp

Ant

 

[Steve]

Oil pressure adjustable relief valve on Lycoming engine...

 

[Tom-D]

Not all Lycoming engines have them. And that one is not secured properly

 

[SCCutler]

Not all Lycoming engines have them. And that one is not secured properly

I wuz gonna say- the screw (w/ slot) is used to adjust, the castle nut is supposed to lock it down by "jam," right?

 

[Steve]

Not surprising in re the assembly configuration since the picture was taken at MAINTENANCE FACILITY.

Not all Lycoming engines have them. And that one is not secured properly

 

[jshawley]

I don't know if the aircraft service manuals allow for this, but perhaps you can verify that your panel gauge is correctly reflecting the actual oil pressure by using a known good, accurate test gauge that you can temporarily install in the same port that your panel gauge plugs into.

Vary engine rpm (say, idle, 1000, 1500, 2000), note the pressures, remove the test gauge, then repeat with the panel gauge (or vice versa--just keep all the outside variables--ambient temp, engine temp, &c--controlled so as to get meaningful data). Of course, all this needs to be done by a bona fide A&P/IA.

(BTW I'm not an a&p, nor have I stayed at a Holiday Inn Express since September--but I am mechanically minded and used to be a metrology technician, so take what I say with the proverbial grain of salt.)

Later,