Oil psi drops the higher I climb

Re: Oil psi drops the higher I climb

by Darryl Zubot » 7 years ago

Darryl Zubot

2 16 2

Hey Roger, interesting, did these aircraft also lose oil pressure the higher they climb? It's consistent how I lose pressure about 1-2 psi every 1000'. Yesterday I replaced all my oil lines with stiffer line (AER FBN0800) as well as the thermostat to a P6-H-205. I now have better oil pressure at high altitude, I always have good pressure on the ground or low altitude but lose pressure the higher I climb, ground level its 50, 1000' - 45psi, 10,000' -33psi, 15,000' 25psi, these numbers are from today after flying the new oil lines. I had 23psi at 10,000' before this. I found many zip ties were crimping the lines, they were installed way too tight from factory. I might consider trying a radiator with built in thermostat, this would reduce oil lines significantly, but still doesn't make sense how I lose pressure the higher I climb, not to this extent at least. Again when I go to idle or low rpm at high altitude my oil pressure instantly increase to good values 45-50 but drops as soon as rpm is set to cruise.

Re: Oil psi drops the higher I climb

by Darryl Zubot » 7 years ago

Darryl Zubot

2 16 2

See pics of original oil lines

IMG_4211.JPG (You do not have access to download this file.)

IMG_4224.JPG (You do not have access to download this file.)

Re: Oil psi drops the higher I climb

by geoffrey klestadt » 7 years ago

geoffrey klestadt

27 94 94

Not enough pressure in the oil tank?

Re: Oil psi drops the higher I climb

by Darryl Zubot » 7 years ago

Darryl Zubot

2 16 2

I have really good pressure during take off, 50psi at idle and 60-70 at take off power. Then it drops off to about 40 at 1000'agl. The odd thing is at high altitude where I have less pressure when I go to idle my pressure increases to 45-50 but with cruise rpm oil psi drops off.

It's apparent that I my oil pump works. Something is restricting the flow during climbs, maybe it still is a bend in an oil line but doesn't make sense how I lose pressure the higher I climb, why would altitude change oil pressure? If I had a kink I would have low pressure all the time or if there is not enough pressure in the system I would always have low oil pressure, pressure at take off is great, no signs of issues until climbing.

Can the propeller governor have anything to do with pressure loss? We have hydraulic props am wondering if this is causing issues for us. There is no leak in the system, I am not losing any oil, I fly 100 hours every couple months and rarely have to add oil between oil changes.

Re: Oil psi drops the higher I climb

by Darryl Zubot » 7 years ago

Darryl Zubot

2 16 2

Here is link to video of how the oil pressure increases when rpm is reduced and vice versa.

https://vimeo.com/user2554293/review/279874617/b0b5532094