Oil pressure question

[Joffreyyy]

Hey all quick question about an older c-150 im kind of stumped. When i start the engine it goes to the green line quickly. ( normal ) I take off fly around for an hour or so oil temp is halfway again normal. However after I land the psi drops to below green inbetween 25 and 30 hard to tell where exactly. If i rev up the engine it goes into the green at 2200 rpm or so but no where near what it was on initial takeoff. Any ideas??

 

[Stewartb]

Warm oil's thinner than cool oil. Normal.

 

[frfly172]

Do you check the oil level when cold? I usually pull the prop through a couple of revs then check the level.

 

[kyleb]

What you're seeing is normal. Not that you have an O-320 in the C-150, but on an O-320, the idle oil pressure needs to be 25 PSI or greater and the pressure needs to be 60 PSI or greater at "operating rpm" or words to that effect.

 

[Norman]

Do you check the oil level when cold? I usually pull the prop through a couple of revs then check the level.

What does that accomplish? You can't move much more than a thimble-full of oil pulling the prop thru.

 

[Joffreyyy]

What you're seeing is normal. Not that you have an O-320 in the C-150, but on an O-320, the idle oil pressure needs to be 25 PSI or greater and the pressure needs to be 60 PSI or greater at "operating rpm" or words to that effect.

Right my concern though is the range its in is below the green line. While ideling after landing its about 25 (1000 rpm) Not by much normal operating range or green line ill call it is 30-60 red line minimum ideling is 10 psi on the poh you guys think im ok even if at say 1800 rpm its still maybe 27-29 psi ? thanks!
P.s. Oil level while cold is full.

 

[frfly172]

What does that accomplish? You can't move much more than a thimble-full of oil pulling the prop thru.

I have a fadec ,and when you pull the prop through it tells the sensor oil is moving. Also seems to show actual level on the stick.

 

[kyleb]

Right my concern though is the range its in is below the green line. Not by much normal operating range or green line ill call it is 30-60 red line minimum ideling is 10 psi on the poh you guys think im ok even if at say 1800 rpm its still maybe 27-29 psi ? thanks!
P.s. Oil level while cold is full.

Yes, you're fine. Trust the POH.

 

[Joffreyyy]

Yes, you're fine. Trust the POH.

Thanks for the reassurance guys all i needed.

 

[Tom-D]

Thanks for the reassurance guys all i needed.

Maybe, maybe not, What oil are you using?

your 0-200's minimum oil pressure is 5 PSI at 550 Idle

but when in good condition the 0-200 will never show oil pressure out of the green when using 40 to 50 weight. but it will when running 15/50.

 

[Tom-D]

Right my concern though is the range its in is below the green line. While ideling after landing its about 25 (1000 rpm) Not by much normal operating range or green line ill call it is 30-60 red line minimum ideling is 10 psi on the poh you guys think im ok even if at say 1800 rpm its still maybe 27-29 psi ? thanks!
P.s. Oil level while cold is full.

The symptoms you describe are the ones we see of tired old engines.