Oil cooler/temp question

Messages
80
Location
SW
I added an oil cooler. It is not done btw.....  - My temps went from 110-115C to 85-90C. This is in the dead hot Arizona summer. I fear in the winter time, if you can call it that, my oil may run too cool. This morning on the way to work it was close to 100 degrees at 8 AM and the oil failed to break 82C on the highway at 3200 rpm's for a 20 minute stretch. The thing is, if I add a thermostat, it may help the oil get hot sooner, but it opens at 80C anyhow, so presumably the oil will alway be real close to 80C. Is this too cool? I assume if I get on it hard and boost alot I could drive temps up some, but in general is 80-90C too cold? I need viscosity so I need 40-50 weight. Thanks
 
Messages
12,385
Location
Northern CA
Nice looking installation! 80C is a cool, you should run your oil at 90C or a bit warmer. The best answer would be a 90C or 95C thermostat. A not so bad kludge would be different sized blocking plates (even pretty cardboard) to block off part of the heat exchanger. 30 wt at 100C will be about the same viscosity as your 40-50 weight was at 115C.
 
Messages
5,112
Location
Airlie Beach Australia
Hi, it is extremely unwise NOT to have a thermostat for your oil cooler - even with a heat exchanger type You really want the oil's temperature to be around the coolant's temperature most of the time. Typically the oil cooler's thermostat should open at around 5-10C above the coolant thermostats's "crack" point (eg at 90-95C if the coolant thermostat opens at 85C) It is all a case of the cooler's capacity/air flow and etc but usually an oil cooler should only be open for long periods under extreme conditions - they should "cycle" in a narrow band of about 15C You may also consider putting a mesh barrier in front of your cooler to prevent damage from flying debris - I certainly would! Regards Doug
 
Messages
39,805
Location
Pottstown, PA
 - Mocal thermostats, as do Permacools, come set at 180°F ..but can be ordered at higher temps. BAT, Inc My next move, on admittedly less exotic and far less potent alloy, will be to adapt three exchangers. One sandwich from a Ford/Mopar and two from the Crown Vic rad hose type. One upper and one lower. Then a thermostat to my mega canister ..perhaps without the filter in it and use it as a reserve sump (about 4.5 quarts capacity)..and maybe even a rad type added in for good measure. I have a 180 Permacool collecting dust. Everything should be balanced out nicely with heat being shunted wherever there's a vacancy.
 

jdmboy

Thread starter
Messages
80
Location
SW
quote:
oil cooler's thermostat should open at around 5-10C above the coolant thermostats's "crack" point (eg at 90-95C if the coolant thermostat opens at 85C
OK. My factory thermostat is 78C. Inline 90C thermostat seems to be the ticket. Wouldn't the default 82C thermostat be too cool for just about everybody though? And yes factory mesh covers are coming as well. [Smile]
 
Messages
39,805
Location
Pottstown, PA
quote:
Wouldn't the default 82C thermostat be too cool for just about everybody though?
That would depend on what viscosity you want your oil at. 20F isn't going to alter much in the way of moisture purging. So you run a lower visc if it makes that much of a difference [I dont know] 100C isn't some magic goal line for anything accept where the refiners spec their oils. What do you see as a down side to a 20F difference to the cooler side [Confused] ..assuming that the visce at that temp was proper for your application?
 

jdmboy

Thread starter
Messages
80
Location
SW
I really do not know. Not sure how to answer. I ran M1 30Wt and my 2 UOA's had lots of lead. I suspect viscosity related. So I stepped up a bit. No way I am going back to 30Wt. Should probably be runnig 20W-50 really. All I want to know is with 5W-40 A3/B4 rated oil and 8000 rpm and lots of boost and 220hp per litre, how low is too low for oil temps? High does not concern me now as the cooler fixed my 120C oil temps. Now I am worried about being too cool in the winter months. Well Az. winter but still winter. If I stay at 80-85C is that OK? And is so should use a multi viscosity with a higher cold rating as it seems I need viscosity? That is all I care about really. Just trying to dial in my oil selection for a hot turbo motor that actually earns it's living. [Smile] I want to protect it.
 
Messages
39,805
Location
Pottstown, PA
Well, like XS650 asserted, your true visc is a sliding scale depending on oil temp. You may still be able to use your 30 weight if you go unregulated with your oil cooler and it never reaches a temp where it is too thin. You can't possibly suffer ill effects of too cool an oil in your climate with 100F ambient temps. OTOH, if you STILL see 115C oil temps when you flog your engine even with your cooler, then you will probably need to go up in weight. Go here and plug in your chosen oil's 40C and 100C spec in the top table using 100% as the ratio. Then go to the bottom table and plug in your peak temps (or target temp) in the lower table. You'll then see what visc your oil will be at ..at a given temp. You should then, between oil spec visc and regulated actual temp, be able to see what works in terms of equivalencies. If you don't ever exceed 100C with your setup now ..and find that a 40 weight reduces your Pb to normal levels ..then you only need a 100C thermostat. You won't be dragging around unnecessary high visc oil during warm up. The same could be said of any weight oil at a higher or lower temp that you dial in ..assuming that your air/oil exchanger is big enough.  - Here is what 5w-40 Delvac 1 looks like at 80C. If I read the visc chart correctly ..this is a 60 weight at this temp.  - [ July 28, 2005, 09:38 AM: Message edited by: Gary Allan ]
 
Messages
783
Location
Austin Texas
quote:
Originally posted by jdmboy: All I want to know is with 5W-40 A3/B4 rated oil and 8000 rpm and lots of boost and 220hp per litre, how low is too low for oil temps?
Any oil thicker than 20 centiStokes is too thick, so with a xW-40 oil at 14 cSt at 100dC anthing cooler than 85dC (185dF) or so is going to be too thick. If you choose the xW-40 for its operating viscocity (14 cSt) you want to run this oil at the viscocity you choose it for. Running it at 85dC is pretty similar to running a xW-50 oil at 100dC -- viscocity wise. Once you add the screen in front of the oil cooler, you can simply apply some duct tape in the winter to prevent overly cool oil. Race engines do not use a thermostat (just one more thing to go wrong) and adjust oil (and water) temps with duct tape.
 

jdmboy

Thread starter
Messages
80
Location
SW
quote:
Here is what 5w-40 Delvac 1 looks like at 80C. If I read the visc chart correctly ..this is a 60 weight at this temp
How can a 5W-40 multi grade be a 60wt? I though the oil was thinner when cold and thicker when hot? Shouldn't it be thinner when cooler and only get not the otherway around, and how does it get to 60? It is a 40Wt. Man oil is confusing. [I dont know] Yes, I was using a mask of sorts kind of like truckers with the coolant radiators in winter as well.
 
Messages
39,805
Location
Pottstown, PA
Okay, relax, jdmboy [Smile] Your confusion is understandable. Here's the short. I can't articulate the "long list". All oils are thicker when cooler. The first number you see is a cold "spec" ..not a weight per se`. The "40" is the visc that it is reduced to at 100C That is, when someone says "a 40 weight will be heavier when hot" ..is really saying "a 40 weight won't thin as much (and not said) as a 30 weight will (at that temp). Okay ..so a 40 weight is only a 40 weight (the span of the spec) in a very narrow temp range. Below that temp ...it would not be the same viscosity ..it would resemble a heavier weight oil. So ...you take Delvac 1 5w-40 ..and ONLY let it GET to 80C ...it then qualifies for a 60 weight at that lower temp. The engine feels like its got a 60 weight oil. The parasitic losses (the hp to pump it) are the same (or very near) as a 60 weight oil in how it taxes the engine. See what I mean? Let's take the 30 weight that you used ..and got Pb wear from. Look at the visc image. 9.3-12.49 CST (at 100C). You, now that you put your cooler on, only reach a peak temp of 90C ...so let's take a 30 weight that I have spec's for ... PZ LL 10w-30 40C cst 78 100C cst 11.7 This will have a 14.7 cst viscosity @ 90C ..identical (almost) to D1's 40 weight spec @ 100C So ..if you only hit 90C now ..and your 30 weight had a 100C visc of at least 11.7 cst ...then it's is now a 40 weight at the hottest temp you've obseved so far since the cooler installation. That's the thinnest it ever gets. What oil did you run? What oil are you running now??
 

jdmboy

Thread starter
Messages
80
Location
SW
Thankis for trying to explain this to me. I am getting it but not quite there yet.I appreciate it. I will get it and more importantly understand what the UOA is saying relative to viscosity and shear. Thanks. Here is my post with the oils and the UOA's. My UOA's do not have the Cst colums filled in just the Sus. Where do you get shear from inh the UOA? http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=002726 Basicly I ran Mobil1 5W-40 then Mobil1 10W-40 and now PZ 5W-40 Synthetic Euro blend. The 2 Mobil UOA'a had high lead. Not done the PZ analysis yet. My oil temps were 90C last Dec going up to 105C through June. The oil etemps went to 115C+ when temps hit 115F out here. Now with the oil cooler and PZ Euro I am 85C-90C. My Penz is A3/B4 rated unlike the Mobil1 so fingers crossed. [ July 29, 2005, 12:30 AM: Message edited by: jdmboy ]
 
Messages
5,112
Location
Airlie Beach Australia
Hi, just because the oil cooler thermostat opens at say 90C does not mean that it (the oil temperature) will remain at that level It will depend on the heat input and the outgoing heat transfer rates. This is also a factor of the cooler's efficiency (size, air flow etc)and the residual heat of the coolant in the sump A good trial is to use a IR reader and take "snapshots" of the "in sump" oil temperature under a variety of your operating conditions. Remember too that you are adding another layer of engine cooling with the addition of an oil cooler so some practical reasearch and testing will make it a worthwhile project Many people continue to run a high viscosity lubricant without justification after adding an oil cooler "layer" to the engine. I like your attention to the A3/B3 rating though - that is sensible IMHO so is at least considering a Porsche Approved and Listed oil in 0w-40/5w-40 viscosity. And you are right to assume that many engines (especially all aluminium ones) struggle to reach the coolant thermostat's crackpoint in very cold conditions Regards Doug
 
Messages
39,805
Location
Pottstown, PA
quote:
Basicly I ran Mobil1 5W-40 then Mobil1 10W-40
There was a little confustion in the UOA post as well. Don't you mean M1 5w-30 and 10w-30???? Isn't PZ Euro synth 5w-40 the first 40 weight you've run?? You would really shatter some paradigms if you managed to beat up Mobil T&SUV/D1. Although the M1 30 weight didn't seem to have any issues of its own in the UOA.
quote:
just because the oil cooler thermostat opens at say 90C does not mean that it (the oil temperature) will remain at that level
Just so you're not confused, Doug. The 90C figure I quoted wasn't pulled out of thin air. That's his reported Delta T with the installation of the cooler unregulated. Flogging it before 115C peak ..flogging it now 90C peak. All that is required to assure a "stable" oil temp is to have a thermostat ..and a big enough exchanger to assure that you can dump any excess heat. Under his current routine of spirited driving, it appears that he has a big enough radiator/cooler ..just no regulation. He doesn't break 80C in normal driving of 20 minutes of duration. His oil never thins to spec in either mode of driving. The only reason that I perceverated on different temps, and the "effective" viscosity, is because this is how most who are unregulated have to view our oil in service. My oil temps are pretty much stable across all viscosities in highway useage. Let's say 160-180 degrees over a 40-50F change in ambient. My 40 weight is the thickness of a 60 weight ...the 50 weight is a 70 weight ..and my 20 weight can be either a 30 weight or a 40 weight depending on where that 20F shift is only since 20weights are almost exclusively always spec'd just below the 30 weight threshold. I think that I'd also check into the lead substitute that you're using since only Pb seems out of whack in your UOA. It wouldn't be the first time that a mix wasn't contaminant free for a given lot # from a producer of both products. Here's the accepted conversion formula for Cst:SUS visc: cst= 0.226xSUS-(195/SUS).
 

jdmboy

Thread starter
Messages
80
Location
SW
[Duh!] Typo ********************************************** Basicly I ran Mobil1 5W-40 then Mobil1 10W-40 ********************************************** [Smile] Correct ********************************************** Basicly I ran Mobil1 5W-30 then Mobil1 10W-30 ********************************************** I am running no Torco at all this cycle and I am hoping the PB is viscosity related. I have used cases of it over the last 6 months. With SW 91 octane getting to 95 octane with a feisty turbo motor is most important. As of now I am driving like a grandmother on waste gate boost. Thermostat is on the way. Think the Pb could be viscosity related and that A3/B4 may help? Stick with A3/B4 40wt stuff or try the M1 Delvac? I just want protection as the motor earns it's living. [Cheers!] [ July 29, 2005, 03:44 PM: Message edited by: jdmboy ]
 
Messages
39,805
Location
Pottstown, PA
See what your current PZ Euro stuff yields in the 5w-40. That should reduce your Pb if it is visc related. I'm not much into the A3/B4 spec's since I just need a good 40 weight for my boring, but stout, domestic pig iron. Anyway ..after you sort out that this is indeed a visc issue, then you're only left with finding the best 40 weight for your needs. Although it doesn't carry all the fancy spec's, D1/T&SUV is a great 5w-40. You may consider it if your results with other heavier spec'd synths give less than stellar results. There's also some of the heavier 30 weights that may serve you well since you've taken care of your peak oil temp issue. Good luck! btw-what thermostat did you order and, if an option, what temp did you spec??
 

jdmboy

Thread starter
Messages
80
Location
SW
D1/T&SUV = Mobil1 Delvac? I ordered the mocal 85C thermostat. The same one you posted. My coolant thermostat is 73C unit. If I flog the car I can drive temps way up in the summer in stop and go city driving even with the oil cooler. I guess that is the benifit of a remote oil cooler and fan with a switch.
 
Messages
39,805
Location
Pottstown, PA
D1/T&SUV = Mobil1 Delvac? All apparent evidence indicates that Delvac 1 is M1 T&SUV. The spec sheets are identical where common items exist (visc, etc.)...to the letter. It would make sense since it would be an easy rebadge of D1 instead of reformulating a whole new oil in the 5w-40 weight. Both are CI spec'd for diesels Delvac 1 Typical Properties Mobil Delvac 1 5W-40 SAE Grade 5W-40 Viscosity, ASTM D 445 cSt @ 40ºC 102 cSt @ 100ºC 14.8 Viscosity Index, ASTM D 2270 151 Sulfated Ash, wt%, ASTM D 874 1.35 Total Base #, mg KOH/g, ASTM D 2896 12 Pour Point, ºC, ASTM D 97 -45 Flash Point, ºC, ASTM D 92 226 Density @ 15ºC kg/l, ASTM D 4052 0.854 TSUV Typical Properties Mobil 1 Truck & SUV SAE Grade 5W-40 Viscosity, ASTM D 445 cSt @ 40ºC 102 cSt @ 100ºC 14.8 Viscosity Index, ASTM D 2270 151 Sulfated Ash, wt%, ASTM D 874 1.35 Total Base #, mg KOH/g, ASTM D 2896 12 Pour Point, ºC, ASTM D 97 -45 Flash Point, ºC, ASTM D 92 226 Density @ 15ºC kg/l, ASTM D 4052 0.854 Here's where the differences appear. Specifications & Approvals Mobil 1 Truck & SUV meets or exceeds the following industry specifications: API gasoline engine standards SL,SJ API diesel engine standards CI-4, CH-4, CG-4, CF-4, CF Specifications & Approvals Mobil Delvac 1 Meets or Exceeds the following industry and builder specifications: 5W-40 API CI-4 PLUS/CI-4/CH-4/CG-4/CF-4/CF/SL/SJ X ACEA E5/E4/E3 X Caterpillar ECF-1 X Cummins CES 20072/20071 X Detroit Diesel Power Guard Oil Specification X Global DHD-1 X JASO DH-1 X Mobil Delvac 1 5W-40 has the following builder approvals: 5W-40 Cummins CES 20078/20077/20076/20075 X Mack EO-N Premium Plus 03, EO-M Plus X Mercedes Benz 228.5 X Volvo VDS-3, VDS-2 X They don't include this information for the T&SUV [I dont know] btw- even though you're using a 73C thermostat, does your coolant temp exceed that under normal driving? If not, I wouldn't bother with anything below a 180F thermostat since many of your PCM/ECU functions depend on the coolant reaching that temp. All that you're doing is giving a "head start" or time buffer for when the heat soak occurs ..but you're paying in spades in normal driving because of it. Just like the size of your oil cooler rad, if the coolant rad is big enough, it should maintain whatever temp the thermostat is set to.
 
Messages
39,805
Location
Pottstown, PA
If you really want to balance out your system nicely, you may want to look into something like this:  - The excess heat will go wherever there's a vacancy...which would be your aux cooler above 180F
 
Top