O-360 oil pressure

simtech

simtech

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Simtech
Well I'm finally getting used to my new to me plane. I notice however that the oil pressure is always at 60 whether idle or in cruise. I talked with my mechanic and he said it is regulated and it was fine. My oil temp never rises above 180. I would have thought with an engine driven oil pump with rpm would give you more oil pressure.

Going on that it's true, would it be beneficial to up the pressure some by adding washers to the vernatherm valve? I'm gonna hook another gauge up inline just to make sure but given the oil temp is fine I'm sure all is good with my mechanic watching. I jut didn't realize the vernatherm regulates pressure like that...keeping a constant pressure under all loads. My chevy fluctuates as I hit the gas..I never paid attention in planes..normally I chck pressure and the needle is up and I never watch. Now that I own i pay more attention to things I didn't normally.
 
Your terminology is mixed up. The oil pressure relief valve regulate pressure. The vernarherm diverts oil to the cooler.
 
simtech said:
Well I'm finally getting used to my new to me plane. I notice however that the oil pressure is always at 60 whether idle or in cruise. I talked with my mechanic and he said it is regulated and it was fine. My oil temp never rises above 180. I would have thought with an engine driven oil pump with rpm would give you more oil pressure.

Going on that it's true, would it be beneficial to up the pressure some by adding washers to the vernatherm valve? I'm gonna hook another gauge up inline just to make sure but given the oil temp is fine I'm sure all is good with my mechanic watching. I jut didn't realize the vernatherm regulates pressure like that...keeping a constant pressure under all loads. My chevy fluctuates as I hit the gas..I never paid attention in planes..normally I chck pressure and the needle is up and I never watch. Now that I own i pay more attention to things I didn't normally.
Click to expand...

If the oil pump can deliver the proper volume of oil ,no matter the temp of it, the limiting factor for pressure is the relief valve setting...

So, If it is set at 60 psi, it will dump any excess back to the sump and maintain 60 psi......
 
Norman said:
Your terminology is mixed up. The oil pressure relief valve regulate pressure. The vernarherm diverts oil to the cooler.
Click to expand...

Well yep I did and that makes sense.. I actually thought they were one in the same..
 
N801BH said:
So, If it is set at 60 psi, it will dump any excess back to the sump and maintain 60 psi......
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Is there any benefit to raising it to say 70 or 80 psi? Or just leave it..60 is in the green but right at the low end of green.
 
simtech said:
Is there any benefit to raising it to say 70 or 80 psi? Or just leave it..60 is in the green but right at the low end of green.
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Nope.... 60 PSI is perfect.... Any more and the motor uses excess HP to turn the oil pump...

This is one thing where more is NOT better...:no:
 
N801BH said:
Nope.... 60 PSI is perfect.... Any more and the motor uses excess HP to turn the oil pump...

This is one thing where more is NOT better...:no:
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That would be below what the Lycoming direct drive overhaul manual calls for.
 
60 lbs is fine ,would like the temp at 180 or a little higher,to get rid of the moisture.
 
POH says 60....Temp always gets to 180 and I have yet to see it go higher. My buddies warrior is 60 at idle and goes to 80 and WOT..Mine stays at 60 no matter what. Ive looked at an older revision of the manual just now and it just says operating range is 60 to 90psi. As long as it is within that area it is fine. If not adjust the pressure relief. So mine is within so Ill leave it at 60.
 
simtech said:
POH says 60....Temp always gets to 180 and I have yet to see it go higher. My buddies warrior is 60 at idle and goes to 80 and WOT..Mine stays at 60 no matter what. Ive looked at an older revision of the manual just now and it just says operating range is 60 to 90psi. As long as it is within that area it is fine. If not adjust the pressure relief. So mine is within so Ill leave it at 60.
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Count your lucky stars.. Most planes will exceed 180 quite often.. Especially in the summer..
 
N801BH said:
Count your lucky stars.. Most planes will exceed 180 quite often.. Especially in the summer..
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Well Ive only had the plane for 2 weeks now..so...we will see next year when summer rolls around. Just getting used to all the norms right now.
 
simtech said:
POH says 60....Temp always gets to 180 and I have yet to see it go higher. My buddies warrior is 60 at idle and goes to 80 and WOT..Mine stays at 60 no matter what. Ive looked at an older revision of the manual just now and it just says operating range is 60 to 90psi. As long as it is within that area it is fine. If not adjust the pressure relief. So mine is within so Ill leave it at 60.
Click to expand...

If you are pumping enough to make the set pressure at idle, you won't increase pressure with RPM. You don't have a temperature problem, so you don't have an oiling problem. More oil pressure than required to take away the heat will shorten the life and reliability of the oil pump. 60 psi with no heat problems is not something that would concern me. As the pump wears and you start picking up heat problems, you may want to turn the pressure up then.
 
In a Lyc higher pressure is better to get more oil to the rocker boxes/valves. It is a ****-poor design to get oil there, and borderline inadequate. Notice that the "new" Cessnas have much higher oil pressure "green" ranges than the legacy ones...presumably to help the valves last longer.
 
mondtster said:
Section 9 covers test procedures and calls for 75-85 psi.

http://www.7ts0.com/manuals/lycoming/DirectDriveOverhaul.pdf
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N801BH said:
Glad you pointed that out... Seems all aircraft POH's are incorrect..:rolleyes:

Page 14 shows operating limits....

http://11hc.44rf.com/manuals/engine..._ops_manual/sec_3a-operating-instructions.pdf
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I don't see a conflict. One document is discussing where the pressure should be set at overhaul, the other what the acceptable pressure is for an installed engine during its life.

KSMooniac said:
Notice that the "new" Cessnas have much higher oil pressure "green" ranges than the legacy ones...presumably to help the valves last longer.
Click to expand...

Or maybe because the new Cessnas have Lycoming and the (vast majority of the) old ones Continental?
 
timwinters said:
I don't see a conflict. One document is discussing where the pressure should be set at overhaul, the other what the acceptable pressure is for an installed engine during its life.



Or maybe because the new Cessnas have Lycoming and the (vast majority of the) old ones Continental?
Click to expand...


No Conflict.......

The OP was asking about the pressure of his motor in his (new to him) plane... Unless it was just overhauled, my 60 PSI comment stands..:rolleyes:
 
simtech said:
Well I'm finally getting used to my new to me plane. I notice however that the oil pressure is always at 60 whether idle or in cruise. I talked with my mechanic and he said it is regulated and it was fine. My oil temp never rises above 180. I would have thought with an engine driven oil pump with rpm would give you more oil pressure.

Going on that it's true, would it be beneficial to up the pressure some by adding washers to the vernatherm valve? I'm gonna hook another gauge up inline just to make sure but given the oil temp is fine I'm sure all is good with my mechanic watching. I jut didn't realize the vernatherm regulates pressure like that...keeping a constant pressure under all loads. My chevy fluctuates as I hit the gas..I never paid attention in planes..normally I chck pressure and the needle is up and I never watch. Now that I own i pay more attention to things I didn't normally.
Click to expand...


Not enough information. Lycoming or Continental?
 
charlie said:
It is quite unusual that the oil pressure is the same at idle and cruise. I would check the gauge calibration. Charlie Melot Zephyr Engines
Click to expand...

This is a very simple task.

Plumb any type of air pressure regulator into the oil pressure line. Simulating oil pressure with air pressure and a known good gauge.


I use these since pretty much every A&P already has one or two. They may be even calibrated.

http://www.aircraft-tool.com/shop/detail.aspx?PRODUCT_ID=2E


I get a cheap air hose long enough to sit in the cockpit with the regulator.

http://www.harborfreight.com/25-ft-x-14-in-coiled-polyurethane-air-hose-61974.html

Be sure to turn the regulator to a low pressure setting before hooking it to your airplane.
 
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