low oil pressure at idle
#31
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Huh??? Well, whatever.....one cannot measure engine oil pressure at the oil filler cap.
This is the quote from the other thread:
Alright, so- we ran through the basic mechanical stuff because it was ~quick. Then we gave up and decided to check the oil pressure. To do this, I ordered a spare oil filter cap/lid, and drilled and tapped a 1/8" NPT hole in the old one. Not a bad trick if anyone else out there needs to check their pressure without tearing everything apart. - That'll be saved in my bin of "special tools".
This is the quote from the other thread:
Alright, so- we ran through the basic mechanical stuff because it was ~quick. Then we gave up and decided to check the oil pressure. To do this, I ordered a spare oil filter cap/lid, and drilled and tapped a 1/8" NPT hole in the old one. Not a bad trick if anyone else out there needs to check their pressure without tearing everything apart. - That'll be saved in my bin of "special tools".
#32
Burning Brakes
Thread Starter
Interesting. Worth a discussion. I wonder if Peter got it to work then. Pressure is force exerted in all directions equally in a fluid in a closed system, so you'd think that pressure could be measured anywhere in the system? I'm just brainstorming here.
Lol, now I want to try it just to see if it works.
Lol, now I want to try it just to see if it works.
#33
Captain Obvious
Super User
Super User
#34
Captain Obvious
Super User
Super User
Interesting. Worth a discussion. I wonder if Peter got it to work then. Pressure is force exerted in all directions equally in a fluid in a closed system, so you'd think that pressure could be measured anywhere in the system? I'm just brainstorming here.
Lol, now I want to try it just to see if it works.
Lol, now I want to try it just to see if it works.
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JohnCA58 (05-19-2020)
#35
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I got the idea from here:
https://rennlist.com/forums/996-turb...-pressure.html
I like that it would be quick and easy to do this, rather than mess around with the oil sender unit. There a reason it would be bad? An extra cap is nothing to get.
https://rennlist.com/forums/996-turb...-pressure.html
I like that it would be quick and easy to do this, rather than mess around with the oil sender unit. There a reason it would be bad? An extra cap is nothing to get.
#36
Rennlist Member
That only works when fluids are not moving (static). As soon as the fluid moves, pressure differs everywhere along the path traveled (infinitely).
#37
Burning Brakes
Thread Starter
Don't worry, I am measuring form the spot you all say. But I want to try this out just for giggles.
#38
Race Director
Yeah but pressure is just resistance to flow, so in a narrow oil galley pressure will be different than when it floods into lets say the oil pan or even in the large pick up tube
#39
Burning Brakes
Thread Starter
But resistance to flow is viscosity and not related. Pressure is force over surface area and does not change within a closed system. But if the fluid is separated into different closed systems, then pressure can be different in each system.
Last edited by jim010; 05-20-2020 at 01:39 PM.
#40
Rennlist Member
Dynamic pressure is used to calculate forces when a fluid is moving.
Think of a garden hose that’s 10’ long versus one that’s 100’ long attached to the same valve. The 100’ hose will flow slower than the 10’ hose, even if both have the same 50 lbs or pressure coming from the valve because the overall resistance in the 100’ hose will slow the water down. That resistance is force that counteracts pressure forces.
If the hose is long enough, there will be no water coming out the other end of the hose. If that’s hard to believe, try to image a hose that long and the weight of the water in that hose, and tell me if you think you can push it, pick it up, or even move it. The weight is one problem, but the friction is really the major component.
#41
Rennlist Member