What's considered too much oil pressure?
#1
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I just built a 454 500hp. Oil pressure seems high 60psi at idle and 70 psi on plane. I put 40hrs on it so far. Is this considered to much oil pressure?
#2
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#3
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me to!
#9
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I just went through this on my jet boat. My oil pressure was at 60 at idle, and 80 anything over idle. I was worried about draining the pan on a longer high RPM blast. 80 is pegged on my gauge and did not let me see a spike if anything weird happens.
What oil are you running?
I went from SAE 30 dino straight over to 15w50 Mobil1 synthetic. My pressures dropped a bit. I am now just below 60 at idle, and higher RPMs are around 70-75. This at least lets me see a spike.
My motor is a ZZ502 with very tight clearances. It sounds like your new motor is very tight too. Your oil pressure will probably drop a bit as it breaks in a bit more.
What oil are you running?
I went from SAE 30 dino straight over to 15w50 Mobil1 synthetic. My pressures dropped a bit. I am now just below 60 at idle, and higher RPMs are around 70-75. This at least lets me see a spike.
My motor is a ZZ502 with very tight clearances. It sounds like your new motor is very tight too. Your oil pressure will probably drop a bit as it breaks in a bit more.
#10
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keep in mind any form of pressure is a product of resistance. The old timers from GM thoughts were basically 10lbs psi of oil pressure for every 1000 rpms. Yes you can basically say that can hold some water today on their thoughts.
Also too much oil pressure is not a good thing as it can cause cavitation in the oil pump. Also oil filters and oil type and oil weight have an effect on oil pressures plus bearing clearances play a role in oil pressures..
Believe it or not the LSA Marine Motors from Indmar and PCM the oil viscosity is 5 w-30 to be used. If you were to use Merc 25w -40 or 20w 50 it would cause higher oil pressure readings in those engines. Also the bearing clearances are tight in those engines as well.
The persay rule of thumb for tight bearing clearances are the tighter - run lower viscosity motor oil and the wider bearing clearances use higher viscosity motor oils. And of course oil viscosity has a direct relation of oil flow as to how fast or how slow it will flow thru out the engine.
Also too much oil pressure is not a good thing as it can cause cavitation in the oil pump. Also oil filters and oil type and oil weight have an effect on oil pressures plus bearing clearances play a role in oil pressures..
Believe it or not the LSA Marine Motors from Indmar and PCM the oil viscosity is 5 w-30 to be used. If you were to use Merc 25w -40 or 20w 50 it would cause higher oil pressure readings in those engines. Also the bearing clearances are tight in those engines as well.
The persay rule of thumb for tight bearing clearances are the tighter - run lower viscosity motor oil and the wider bearing clearances use higher viscosity motor oils. And of course oil viscosity has a direct relation of oil flow as to how fast or how slow it will flow thru out the engine.