Viscosity Choice based on Oil temp

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Originally Posted By: ZeeOSix
I've never claimed or made it my premise that all bearings need to be pressure fed.


OK...rules have moved again...that was always your premise.
 
Originally Posted By: Shannow
Originally Posted By: ZeeOSix
I've never claimed or made it my premise that all bearings need to be pressure fed.


OK...rules have moved again...that was always your premise.


Nope ... go back and re-read all the prior discussions in those other two older threads.

But your premise hasn't changed because you made the same statement that "the pump doesn't cause flow through the bearing" in this thread, even after all the prior discussions and what seemed like mutual agreement that pressure fed bearings do flow more than un-pressurized bearings - then you reset back to the old viewpoint. Why is the puzzling part. Don't you believe any of the information presented?

But to add, the discussions have been good and I think we both looked beyond the box a bit.
grin.gif
 
A hotter day today at around 30C. Despite this, my max oil temp was still 86. It did drop at some points too when traffic was slower and rpms lower. If I get the chance tomorrow, I will try measure temp with a different device.
 
not that cold. I had a car with factory oil cooler that would run the oil at 80°C until you really upped the rpm for a long time like on the autobahn, then the temp would settle around 100°C
 
Well I'm hardly highway driving. It's all city with some slow 80kmph zones at best. Drive is 19kms which is 11-12 or so miles.
 
Got another question about oils for my engine. At the moment I am running 10W-40 full synthetic high ZDDP oil (Penrite racing). After a hard run oil temps get to around 100degC and pressure drops from around 300kpa/44psi(warm) to about 200kpa/30psi (hot) at idle (1000rpm). Sometimes it drops a bit under 200kpa if I come straight off the track and let it idle and just sets off the low pressure 20psi warning light. It quickly restores after a cool down, and I have an oil cooler and on the cool down lap it drops quite a bit, so cooling is working. Ambient temps during cold months range 5degC - 20degC

Anyway, for the hotter summer months I am thinking using a heavier 15W-50. What do you think ?

When cold at first start up it sits around 350kpa/50psi, when warmed its sits around 300kpa/44psi, and then of course hot after a run can drop to about 200kpa/30psi as stated. This is all at idle @1000rpm. Of course press goes up as rpm increase.


50psi at idle is still decent oil pressure, and the oil temp quickly recovers on cool down lap, so I don't think I have a problem or anything, its more extra protection during the hot summer months. My only concern is going to heavy, but I guess when it reaches higher op temps it wont matter.



Thanks for any advice and guidance
 
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Its 20psi, one of those Longacre brands. 20psi is a bit high I guess, but I wanted one with heaps of leeway. 20psi is the only one they offer. I was going to get the adjustable type but the sender units are bulky, and they only go down to 15psi anyway.
 
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Originally Posted By: TKFD
Got another question about oils for my engine. At the moment I am running 10W-40 full synthetic high ZDDP oil (Penrite racing). After a hard run oil temps get to around 100degC and pressure drops from around 300kpa/44psi(warm) to about 200kpa/30psi (hot) at idle (1000rpm). Sometimes it drops a bit under 200kpa if I come straight off the track and let it idle and just sets off the low pressure 20psi warning light. It quickly restores after a cool down, and I have an oil cooler and on the cool down lap it drops quite a bit, so cooling is working. Ambient temps during cold months range 5degC - 20degC

Anyway, for the hotter summer months I am thinking using a heavier 15W-50. What do you think ?

When cold at first start up it sits around 350kpa/50psi, when warmed its sits around 300kpa/44psi, and then of course hot after a run can drop to about 200kpa/30psi as stated. This is all at idle @1000rpm. Of course press goes up as rpm increase.

50psi at idle is still decent oil pressure, and the oil temp quickly recovers on cool down lap, so I don't think I have a problem or anything, its more extra protection during the hot summer months. My only concern is going to heavy, but I guess when it reaches higher op temps it wont matter.

Thanks for any advice and guidance



I am posting this from a position of almost complete ignorance, but I happened to see a guy on a Forester website selling something called an oil accumulator yesterday and poked around trying to figure out what it was. Seems like it is an extra oil reservoir (this one was 3 quarts) that uses compressed air to raise the system oil pressure when it dips and is then recharged when the system pressure rises naturally from higher RPMs.
I have never heard of somebody using one and would imagine it would add weight that you wouldn't want in a racing vehicle, but I thought it was worth mentioning here.
Cheers!
 
It sounds like a oil breather. The compressed air is you speak of may be crankcase blowby. Its basically a system where an accumulator catches low pressured oil vapour that is sent from crankcase pressure (blowby) before it reaches the intake as modern car engines now plumb crankcase emissions via a PCV (positive crankcase ventilation). Over time or extended high rpm sludge and oil can build up in a n intake. An accumalator catches this oil. Must be drained after a while though. Oil in the intake can reduce fuel octane rating and carbon up the intake path.

Thanks for your comment, but not what I am talking about here
 
Originally Posted By: TKFD
It sounds like a oil breather. The compressed air is you speak of may be crankcase blowby. Its basically a system where an accumulator catches low pressured oil vapour that is sent from crankcase pressure (blowby) before it reaches the intake as modern car engines now plumb crankcase emissions via a PCV (positive crankcase ventilation). Over time or extended high rpm sludge and oil can build up in a n intake. An accumalator catches this oil. Must be drained after a while though. Oil in the intake can reduce fuel octane rating and carbon up the intake path.

Thanks for your comment, but not what I am talking about here


Sounds like you are talking about a catch can...here is a link to manufacturer's page with info about one of their accumulators. I had never heard of these until a couple of days ago and have no idea if they are really useful...
Moroso 3 Quart Oil Accumulator
 
Well just to update my heavily hijacked thread
laugh.gif


My max oil temp was 90C the other day and that took a 45 minute drive and a higher rpm hill climb in 30C weather...

Max each day seems to top out at around 86 on the way home. Morning temps still not getting past 80C.

Forgot to mention I have an engine swapped mx3. Instead of the 1.8L v6 it has a 2.5L V6. Perhaps due to lightness of car the engine is not working as hard?
 
Originally Posted By: KL31
Well just to update my heavily hijacked thread
laugh.gif


Pirates everywhere mate.

This might be of interest to you, it's from a thread about engine oil temp in air-cooled Japanese motorcycles.

Most report temps from 60 to 90 degC, with 80 C being a typical operational road temperature. Similar to the temps you are seeing.

Quote:
I purchased the KEDO RR temp gauge from Vintage Spoke. (There are less expensive ones on eBay, but only KEDO had the black face which matches the instrumentation on my 1979 SR500F.) Now I can see how quickly the oil temp starts to register after start-up, how long it takes to get to the optimal performance level (literature said that's about 80ºC), and the correlation between the ambient temp and +/- oil temp when ridding the bike in a similar fashion in measurably different weather. For instance, one day this past week the oil topped at an indicated 60ºC no matter how I rode the bike; the following, warmer day, it was pegged at 80ºC no matter how I rode.


Quote:
The only time my RR gauge has crested the 80ºC mark (indicated for whatever that's worth) during the past few weeks was in a construction-zone traffic jam while riding the clutch for a bit, and even then, it only did so by a few degrees


These Yamaha air-cooled thumper engines were used in both road bikes and dirt bikes, I'm sure they run cooler on the road, and hotter pushing through slow sand under heavy loads. They have been used for decades and are considered very robust. It seems the common road temp reported is 80C. This makes sense to me, if they were 100C at normal road riding, then where do you go when you hit the slow dirt road sections? You want it to be at max temp only under extreme riding conditions, not before. I know water cooled cars offer more temp control, but air-cooled bikes show what is acceptable.

http://www.sr500forum.com/forum/viewtopic.php?f=74&t=12784

http://www.sr500forum.com/forum/viewtopic.php?f=74&t=12784
 
Originally Posted By: TKFD
Got another question about oils for my engine. At the moment I am running 10W-40 full synthetic high ZDDP oil (Penrite racing). After a hard run oil temps get to around 100degC and pressure drops from around 300kpa/44psi(warm) to about 200kpa/30psi (hot) at idle (1000rpm). Sometimes it drops a bit under 200kpa if I come straight off the track and let it idle and just sets off the low pressure 20psi warning light. It quickly restores after a cool down, and I have an oil cooler and on the cool down lap it drops quite a bit, so cooling is working.

When cold at first start up it sits around 350kpa/50psi, when warmed its sits around 300kpa/44psi, and then of course hot after a run can drop to about 200kpa/30psi as stated. This is all at idle @1000rpm. Of course press goes up as rpm increase.


Not sure what car you have, but it sounds like you have plenty of oil pressure with the Penrite Racing 10W-40.

Originally Posted By: ZeeOSix

The "10 PSI per 1000 RPM" has always been a general rule of thumb for GM V8s. It follows pretty good on my Z06. Not too sure it applies to every engine on the road - but every engine with a PD oil pump shows an increase in oil pressure with an increase in engine RPM.

But if you look at Fig 7 in the modeling paper, the main gallery oil pressure at 800 RPM is 225 kPa and the oil pressure at 5500 RPM is 500 kPa. That works out to an average of 8.7 PSI per 1000 RPM ... so really not too far off.
 
Originally Posted By: Virtus_Probi
Originally Posted By: TKFD
Got another question about oils for my engine. At the moment I am running 10W-40 full synthetic high ZDDP oil (Penrite racing). After a hard run oil temps get to around 100degC and pressure drops from around 300kpa/44psi(warm) to about 200kpa/30psi (hot) at idle (1000rpm). Sometimes it drops a bit under 200kpa if I come straight off the track and let it idle and just sets off the low pressure 20psi warning light. It quickly restores after a cool down, and I have an oil cooler and on the cool down lap it drops quite a bit, so cooling is working. Ambient temps during cold months range 5degC - 20degC

Anyway, for the hotter summer months I am thinking using a heavier 15W-50. What do you think ?

When cold at first start up it sits around 350kpa/50psi, when warmed its sits around 300kpa/44psi, and then of course hot after a run can drop to about 200kpa/30psi as stated. This is all at idle @1000rpm. Of course press goes up as rpm increase.

50psi at idle is still decent oil pressure, and the oil temp quickly recovers on cool down lap, so I don't think I have a problem or anything, its more extra protection during the hot summer months. My only concern is going to heavy, but I guess when it reaches higher op temps it wont matter.

Thanks for any advice and guidance



I am posting this from a position of almost complete ignorance, but I happened to see a guy on a Forester website selling something called an oil accumulator yesterday and poked around trying to figure out what it was. Seems like it is an extra oil reservoir (this one was 3 quarts) that uses compressed air to raise the system oil pressure when it dips and is then recharged when the system pressure rises naturally from higher RPMs.
I have never heard of somebody using one and would imagine it would add weight that you wouldn't want in a racing vehicle, but I thought it was worth mentioning here.
Cheers!



Just adding that those are very common on off road rock racing buggies for keeping pressure while facing straight up or sideways...



http://www.pirate4x4.com/tech/billavista/Oiling/#accumulator


Stuff like this:

https://youtu.be/d7BhWqTEyfY
 
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