Oil Temps (again)
Discussion
I have AS 550hp sbc in my can am. With Mocal oil cooler and oil tstat. Under normal running the oil temp never goes above 60degC. I installed the stat which operates at 80degC to try to raise temp to a better level. It made very little difference. Oil temp is correctly calibrated and I have verified the reading by using other temp measuring devices. Oil temp does go up more if vehicle is left idling for ages. It seems that the motion of the vehicle is enough to keep the oil temp down or that the oil stat which does not positively close off the route to the cooler is allowing too much oil to go to the cooler even when it is cold.
Does anybody else with a wet sump set up similar to mine measure their oil temp under normal road and or track use? What readings do you get and are you sure that they are correct? My next move will be to blank off the oil cooler completely to see what I get. I am determined to get a higher oil temp whilst still having a cooler available for when oil does get hotter on track days etc.
Does anybody else with a wet sump set up similar to mine measure their oil temp under normal road and or track use? What readings do you get and are you sure that they are correct? My next move will be to blank off the oil cooler completely to see what I get. I am determined to get a higher oil temp whilst still having a cooler available for when oil does get hotter on track days etc.
Your setup does sound similar to mine, I added an oil stat a year after I got it one the road because of the same low temperature issue you have. I do have a remote filter, this is the first thing in the path of the oil from the engine, from there it goes to the oil stat/cooler and back to the block, with an Accusump T'ed in.
My oil temp sensor is mounted in the top of the filter housing, so is in the flow, with oil picked up from the sump by the oil pump. Without the stat I used to get oil temps well below 80degC with normal road use and on track it used to approach 120degC or more when frashed.
I later added a temp controlled fan to the oil cooler to control the top end, but with the stat with normal road driving it always seems to get up to temp ie >80degC. However, with cool ambients both coolant and oil take an age to get up to working temps. If I watch oil temps you can see it change a little after revving under load and then cool down.
I can not really think what is happening in your setup that would be so different, aspecially as you have tried diffenent temp measuring devices.
My oil temp sensor is mounted in the top of the filter housing, so is in the flow, with oil picked up from the sump by the oil pump. Without the stat I used to get oil temps well below 80degC with normal road use and on track it used to approach 120degC or more when frashed.
I later added a temp controlled fan to the oil cooler to control the top end, but with the stat with normal road driving it always seems to get up to temp ie >80degC. However, with cool ambients both coolant and oil take an age to get up to working temps. If I watch oil temps you can see it change a little after revving under load and then cool down.
I can not really think what is happening in your setup that would be so different, aspecially as you have tried diffenent temp measuring devices.
Not quite the same... but similar issues.
Mine is LS7 dry sump - Ultima oil system with mocal cooler /stat. Measured at the coldest point in the system (bottom of dry sump tank)I get 60-65 deg C driving, rises to about 80 when in traffic or after some spirited driving.
Water comes up to temp really quickly (80 C) in a few mins from cold, oil takes a lot longer to get to 60 C.
Planning on maybe moving oil temp sensor to the gallery feed above the oil filter to see what that gives me. I talked to the factory about the mocal stat plate and was told there's always a path through the cooler as well as the bypass flow back to the tank/sump.
One thing I've not double checked is that the Mocal stat is right way round (I checked during build, but can recall any flow markings) - any have thoughts on this?
Next step is partially blocking the cooler with a cover plate - removable for very hot days or track use.
Mine is LS7 dry sump - Ultima oil system with mocal cooler /stat. Measured at the coldest point in the system (bottom of dry sump tank)I get 60-65 deg C driving, rises to about 80 when in traffic or after some spirited driving.
Water comes up to temp really quickly (80 C) in a few mins from cold, oil takes a lot longer to get to 60 C.
Planning on maybe moving oil temp sensor to the gallery feed above the oil filter to see what that gives me. I talked to the factory about the mocal stat plate and was told there's always a path through the cooler as well as the bypass flow back to the tank/sump.
One thing I've not double checked is that the Mocal stat is right way round (I checked during build, but can recall any flow markings) - any have thoughts on this?
Next step is partially blocking the cooler with a cover plate - removable for very hot days or track use.
paulbuckley said:
Not quite the same... but similar issues.
Mine is LS7 dry sump - Ultima oil system with mocal cooler /stat. Measured at the coldest point in the system (bottom of dry sump tank)I get 60-65 deg C driving, rises to about 80 when in traffic or after some spirited driving.
Water comes up to temp really quickly (80 C) in a few mins from cold, oil takes a lot longer to get to 60 C.
Planning on maybe moving oil temp sensor to the gallery feed above the oil filter to see what that gives me. I talked to the factory about the mocal stat plate and was told there's always a path through the cooler as well as the bypass flow back to the tank/sump.
One thing I've not double checked is that the Mocal stat is right way round (I checked during build, but can recall any flow markings) - any have thoughts on this?
Next step is partially blocking the cooler with a cover plate - removable for very hot days or track use.
Just found this... Mine is LS7 dry sump - Ultima oil system with mocal cooler /stat. Measured at the coldest point in the system (bottom of dry sump tank)I get 60-65 deg C driving, rises to about 80 when in traffic or after some spirited driving.
Water comes up to temp really quickly (80 C) in a few mins from cold, oil takes a lot longer to get to 60 C.
Planning on maybe moving oil temp sensor to the gallery feed above the oil filter to see what that gives me. I talked to the factory about the mocal stat plate and was told there's always a path through the cooler as well as the bypass flow back to the tank/sump.
One thing I've not double checked is that the Mocal stat is right way round (I checked during build, but can recall any flow markings) - any have thoughts on this?
Next step is partially blocking the cooler with a cover plate - removable for very hot days or track use.
http://www.motionaero.com/files/Mocal_Oil_Thermost...
interesting that my scavenge oil (supply to stat) hose is connected to "bolt head" side of stat rather than the other port - configuration is correct per the factory photos and diagrams, but it seems to contradict this document. Just wondering if that is affecting my set up and routing more oil than necessary to the cooler... time to experiment I think!
Hi Mark im with Steve on this one , when you say you have the oil temp sender in the top of sump ? (is it going through the threaded hole on the top of the wing of the sump ? ) is it fully immersed in the engine oil all the time ? ie once oil is circulating and throw in a bit of cornering maybe the sender is only in oil 50 ish percent or the time , just a thought ? what about speaking to your local hydraulic company( or maybe real steel sell one i know burtons do ) and see if they can come up with a conversion sump plug where the plug screws into the sump but it has a threaded hole through the middle where the sender can be screwed into keeping it immersed in hot oil all the time ,
It is in the top of the winged part of the sump. I used this as the supplier of the sump puts it there to measure oil temp. I have made efforts to measure temp in other parts of the system before cooler and have come up with very similar readings.
Darren I have a copy of the install instructions for the stat if you want me to email to you. OK have just seen the link above which shows plumbing. Mine is correct.
Darren I have a copy of the install instructions for the stat if you want me to email to you. OK have just seen the link above which shows plumbing. Mine is correct.
Edited by MarkWebb on Wednesday 23 June 07:53
Edited by MarkWebb on Wednesday 23 June 07:57
You have to decide on what you are trying to assess here. Peak, average or lowest temp's ? There will be quite a difference in various locations and depending on the conditions at the time of measurement, ie has the engine just worked very hard, has the car been moving, is the whole system fully heated, ambient conditions etc etc. If all these parameters are not matched between setups you cannot get a true picture to make judgement.
It sounds like the stat fitted does not reduce flow sufficiently. That being the case, slow the flow down through the stat/cooler.....a smaller fitting perhaps?
It sounds like the stat fitted does not reduce flow sufficiently. That being the case, slow the flow down through the stat/cooler.....a smaller fitting perhaps?
I originally had the sender in the same location, on top of the wing part of the sump. What I saw there was very delayed temp readings, just because the sender is not really in any flow. This maybe ok for a sort of average but putting in in the flow seems to capture what is really going on and does seem to work a lot better. As stateyou are relying on oil being at the sender, which is quite high up. But as 738driver says if you have measured in different places maybe it is time to reduce the flow to the cooler or get it tested (by the manufacture).
Next step is buy 10 JIC to 10 JIC and bypass cooler completely. If this makes the oil hotter then oil is flowing through the cooler when it shouldn't be. There is nothing wrong with the stat. When the oil is cold it allows oil to bypass the cooler by having an open bypass. However the route to the cooler is also open. The oil should bypass because it is the easier route. When the oil reaches 80deg C the stat closes forcing all the oil through the cooler. Reducing the size of the fitting/pipe to the cooler would result in much less oil flow when the oil gets to 80 deg c and above! Just when more oil flow is needed!
Hmm ....you would have to prove improved flow = improved cooling in your particular installation to convince that theory. If the flow through the cooler were slower might it help reduce temp further?..the process of conduction/convection does take time! Also consider, flow rate will increase as viscosity reduces due rising temps.
Stats control temp...... coolers/rads and fans dissipate the excess heat. All you are doing here is trying to manage energy, retain it during warm up, maintain it during normal operation and throw it into the atmoshphere when theres too much.
As previously said I think the first point to sort is what temp you want where otherwise you will go round in circles. In a performance SBC the top end is the weak area, the valve gear suffers and wears the most hence the mods seen in top endurance builds. Maybe you should be taking measurements off the top of the block and rework your system temps from there?
Vizard and many others agree about optimum oil temps but you have to remember who the majority of their readers are. Unless you are mostly orientated around drag racing their information needs modifying to suit each application. Even if you follow the factory standard each build is slightly different..... a 300-800hp range on the same cooler set up is bound to give differing results.
Have fun.
Stats control temp...... coolers/rads and fans dissipate the excess heat. All you are doing here is trying to manage energy, retain it during warm up, maintain it during normal operation and throw it into the atmoshphere when theres too much.
As previously said I think the first point to sort is what temp you want where otherwise you will go round in circles. In a performance SBC the top end is the weak area, the valve gear suffers and wears the most hence the mods seen in top endurance builds. Maybe you should be taking measurements off the top of the block and rework your system temps from there?
Vizard and many others agree about optimum oil temps but you have to remember who the majority of their readers are. Unless you are mostly orientated around drag racing their information needs modifying to suit each application. Even if you follow the factory standard each build is slightly different..... a 300-800hp range on the same cooler set up is bound to give differing results.
Have fun.
Edited by 738 driver on Thursday 24th June 11:08
I want oil to run at 80-100 for norm use max 120 for track use. The oil will then be at the correct viscosity to lubricate the engine and any water that is in the oil through condensation will evaporate out. It seems that in my case (and many others) the natural cooling of the oil is too great to allow the oil to get hot enough for the stat to operate correctly. Allowing less oil through the cooler (if indeed oil is going through the cooler} when the stat does not require it is of course the solution. How to do it is another matter. Reducing pipe size is not an option in my view. A more positive acting stat would be but it must not interrupt oil flow at all as it changes over.
Interesting comment from Jeff and probably correct if my experience anything to go by. I am not aware of any oil stat that works in a different way. The requirement is no interruption to flow when changing over.
Electronic 3 way solenoid valve might work if correctly designed but would need some control to change it over and to make sure that it didn't jump back and forth on the threshold temp. Cold oil shock is also an issue at changeover.
Electronic 3 way solenoid valve might work if correctly designed but would need some control to change it over and to make sure that it didn't jump back and forth on the threshold temp. Cold oil shock is also an issue at changeover.
MarkWebb said:
I want oil to run at 80-100 for norm use max 120 for track use. The oil will then be at the correct viscosity to lubricate the engine and any water that is in the oil through condensation will evaporate out. It seems that in my case (and many others) the natural cooling of the oil is too great to allow the oil to get hot enough for the stat to operate correctly. Allowing less oil through the cooler (if indeed oil is going through the cooler} when the stat does not require it is of course the solution. How to do it is another matter. Reducing pipe size is not an option in my view. A more positive acting stat would be but it must not interrupt oil flow at all as it changes over.
If you want to run two specific temps you need two/split systems or an adjustable stat or fan, and suitable control device.A much smaller oil cooler and electronic switched fan, in conjuction with a stat is the route I have committed to for a slightly higher output than your own.
So as has previously been said, the best way is perhaps not to block the cooler, but to totally bypass with a short out-in pipe loop at the stat, thus no heatloss in the cooler itself?
If proved OK and the cooler is not needed as suggested then pull it all out inc the valve, and plumb the circuit directly to the sump? Then you have room to store warm pasties for all your friends!
Keith
If proved OK and the cooler is not needed as suggested then pull it all out inc the valve, and plumb the circuit directly to the sump? Then you have room to store warm pasties for all your friends!
Keith
Edited by V8 Vum on Thursday 24th June 14:23
In SBC's Keith, you just remove the sandwich plate, refit the original oil filter adapter to the block (if any different) and screw the filter back on. No plumbing/fittings required at all to carry out the test. An accumulator can be easily refitted if required.
The LS motors do seem to run generally cooler too.
Dont forget the Laminova type coolers also, another easier/more consistent option .
The LS motors do seem to run generally cooler too.
Dont forget the Laminova type coolers also, another easier/more consistent option .
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