I've seen in the mid to upper 90's when I first start my 3.6L Rubicon. It drops off pretty fast though. It depends on the engine and how its set up. Once warmed up stopped at a light I have about 33 psi, at 2000 rpm about 44 psi when hot.
Oil pressure too high?
- Thread starter FCD
- Start date
- Status
Originally Posted By: Nick1994
What's wrong with keeping it topped up on oil? So if you run 10w40, and it burns a bit more, what's wrong with that? I'd rather keep my engine happy and topped up on oil than choking on thick oil and not needing to top up so often.
Nick, define "choking" as it applies to engine oils and engine operation ?
What's wrong with keeping it topped up on oil? So if you run 10w40, and it burns a bit more, what's wrong with that? I'd rather keep my engine happy and topped up on oil than choking on thick oil and not needing to top up so often.
Nick, define "choking" as it applies to engine oils and engine operation ?
Originally Posted By: FordCapriDriver
I was just wondering if you guys think it's too high, or that it might indicate a problem.
I've always thought the more oil pressure the better but since reading BITOG threads i've realised you have to find a good compromise and balance between pressure and flow right?
FCD, what you are describing is exactly what every 1970s car I owned did on cold starts.
Peg the OP guage until it warms up, then drop to 15-20psi hot idle.
Nothing wrong with it...it's normal.
the high pressure means that the viscosity in your bearings is such that it doesn't have as much side leakage (bearings draw only that which they need from the pressurised galleries), and the artifact is oil pressure.
Your bearings are getting all the oil that they need...as the oil thins with heat, they need more, draw more, and the pressure drops.
There's a school of thought, inspired by 101, and another vocal poster who do NOT understand the hydrodynamic theory that you need to pump an oil pump volume worth of oil through the engine every revolution to "lubricate", but they are wrong.
If you want, I've explained "side leakage" in this thread on how bearing are designed and work.
Flow is a result of lubrication, not lubrication in and of itself.
I was just wondering if you guys think it's too high, or that it might indicate a problem.
I've always thought the more oil pressure the better but since reading BITOG threads i've realised you have to find a good compromise and balance between pressure and flow right?
FCD, what you are describing is exactly what every 1970s car I owned did on cold starts.
Peg the OP guage until it warms up, then drop to 15-20psi hot idle.
Nothing wrong with it...it's normal.
the high pressure means that the viscosity in your bearings is such that it doesn't have as much side leakage (bearings draw only that which they need from the pressurised galleries), and the artifact is oil pressure.
Your bearings are getting all the oil that they need...as the oil thins with heat, they need more, draw more, and the pressure drops.
There's a school of thought, inspired by 101, and another vocal poster who do NOT understand the hydrodynamic theory that you need to pump an oil pump volume worth of oil through the engine every revolution to "lubricate", but they are wrong.
If you want, I've explained "side leakage" in this thread on how bearing are designed and work.
Flow is a result of lubrication, not lubrication in and of itself.
Originally Posted By: FordCapriDriver
Well it sure is running pretty sweetly "choking" on 20w50 compared to how it ran on 10w40
.
No but seriously do you think i'm harming my engine, i don't think i am, i think about 95% of these cars would have fried engines if that were the case...
To answer your initial question, no it's not damaging your engine; if it went full scale or beyond then perhaps, but only going to 3/4 at startup you should be fine.
Well it sure is running pretty sweetly "choking" on 20w50 compared to how it ran on 10w40
No but seriously do you think i'm harming my engine, i don't think i am, i think about 95% of these cars would have fried engines if that were the case...
To answer your initial question, no it's not damaging your engine; if it went full scale or beyond then perhaps, but only going to 3/4 at startup you should be fine.
My brother found this when changing the filter on his newly aquired BMW R100 a few years ago. I presume 20w50 in a Canadian winter.
Originally Posted By: CT8
What makes you think the oil pressure is too high? Forget everything you read in the oil university.
Blasphemy! But true..
When we go experimenting with oils is when we tend to run into problems.
What makes you think the oil pressure is too high? Forget everything you read in the oil university.
Blasphemy! But true..
When we go experimenting with oils is when we tend to run into problems.
i've ru anything from 10w30 to 20w50 in my engine ( once ran 25w60 but found that too thick ) , with the 10w30 i found the hot oil pressure too low, 10w40 which is what i've run far the past 15 years was ok, but last September i switched to 20w50 to keep down oil consumption and literally everybody ia sked on a Capri forum told me that they used 20w50 so...
Silk, that looks pretty nasty!
Yeah that oil filter looks destroyed, would never ever run any 20wXX in Canadian winters unless the car was kept inside a heated garage
Originally Posted By: Silk
My brother found this when changing the filter on his newly aquired BMW R100 a few years ago. I presume 20w50 in a Canadian winter.
He did well to crush one of the two part filters. It's more common for the single part filter to collapse. Here's mine after a -5 deg C start and too many revs. BMW airheads are known for having very high oil pressure and will easily hit 7 or 8 bar with cold oil. I will never use 20W50 again winter or summer.
My brother found this when changing the filter on his newly aquired BMW R100 a few years ago. I presume 20w50 in a Canadian winter.
He did well to crush one of the two part filters. It's more common for the single part filter to collapse. Here's mine after a -5 deg C start and too many revs. BMW airheads are known for having very high oil pressure and will easily hit 7 or 8 bar with cold oil. I will never use 20W50 again winter or summer.
Originally Posted By: Silk
My brother found this when changing the filter on his newly aquired BMW R100 a few years ago. I presume 20w50 in a Canadian winter.
Look at the crud in the filter pleats! There must be a problem with the filter by pass maybe.
My brother found this when changing the filter on his newly aquired BMW R100 a few years ago. I presume 20w50 in a Canadian winter.
Look at the crud in the filter pleats! There must be a problem with the filter by pass maybe.
I noticed the stuff in the pleats too. Mine was clean though. Maybe his filter was loaded up and that caused the crush, after all it's the differential pressure across the media that does the crushing.
The filter bypass on a BMW airhead is a simple ball and spring. They have been known to fail but open rather than closed. Basically the spring breaks and if you are really unlucky small bits of spring break off and travel through the oil gallery to wreck the main bearings. It's become standard practice for me at a filter change to poke the ball to check the valve is still functional.
The filter bypass on a BMW airhead is a simple ball and spring. They have been known to fail but open rather than closed. Basically the spring breaks and if you are really unlucky small bits of spring break off and travel through the oil gallery to wreck the main bearings. It's become standard practice for me at a filter change to poke the ball to check the valve is still functional.
First oil change on a newly aquired bike, so he doesn't know what happened, and he never mentioned much about the dirty media. He's been riding it a few years now, so obviously the engine is good. Maybe it was started in winter with summer oil. -4C is as low as I've gone on 20W50, and never crushed a filter.
i used 20w40 and 20w50 during Finnish winters when i lived there , altough the car was kept in a heated garage
- Status
Similar threads
