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Thread: Considering a bigger better radiator.

  1. #26
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    Quote Originally Posted by rf900rkw View Post
    I have said it a billion times before. The fan is NOT controlled by engine temp. It is controlled by radiator temp. The fact that your engine outlet temp approaches 100C before 88C coolant reaches the sensor points to a flow problem. Going to an 80C switch will not stress the fan any more, you will end up with nearly the same duty cycle, just at a lower radiator temp. Keep in mind the fan runs any time the A/C button is on.
    What is the highest engine temp you see Randy, with your AC off in FL (key), with your fan delete, if you can? I'm very curious as to what a good flow number is then to shoot for. Idle, and off a freeway doing 80mph for 20-30 minutes or so to a dead stop when engine is heat soaked if you can. AC off. Thanks!

    I had thought the same thing originally low flow. I took the radiator out and flushed it a a year or two back, no apparent flow problem there. I did put in a new BMW water pump about 15k miles ago, possibly this is the suspect of low flow. New BMW T-Sat as well.

    I never ever have a problem, in any condition, with the stock set up. Ever. 114F outside and everything is just fine. Uphill, stop and go, the works. And even without, unless I had my OBD2 I would not ever know of an issue, the gauge on the dash never moves and i would never know (what I am suspecting many fan delete members have done in the past with no real way of knowing temps, "oh its just great!" they claim off the dummy guage). I am not overheating per say, but definitely runs higher temps with fan delete. And only when I press the heck out of it does engine temp get up to 212F, when I am trying to purposely stress testing it on a 100 degree day. For 90% everyday driving with fan delete I am fine. 100% fine in the winter. Sounds like a lot of other forum members on here. "Fan delete was fine until that mountain climb, the gauge moved slightly and I turned on the heat..... but good other than that!"

    When I originally also suspected low flow, I thought that perhaps I would see this problem at speed. Especial at 80-90 mph if that engine isn't getting enough coolant, zipping and churning 4k rpms, especially with the low flow M bumper. But maybe this at speed airflow is just enough to keep radiator heat dissipating and it in check, despite low coolant flow through radiator and thus to the engine block as suggested. And the silly little airflow from the mechanical fan then, for me, is enough to offset everything when at a stop (when heat soaked as well), it is effectively controlling the radiator temp as designed. The electrical fan never comes on. The mechanical fan never even has to lock up 99% of the time, it keeps it that much in check under the hood.

    Going to an 80 degree radiator temperature switch, with the electrical fan turning on and off, will be using the system much much more than originally intended, and by default of using something more, will put extra stress, use, and wear and tear on components used.

    So problem, very possible. Might be time for a new radiator and another new water pump in the near future so that I can confidently run a fan delete. But, over the years, I have read time and time again where this is a problem, only when freshly monitoring temps on OBD2 with a new fan delete, on an otherwise healthy/sound non-over heating car. Some of us in our older age have flow problems. Apparently some Z3's do too! Ha!

    I will be changing out the radiator soon enough, I'll do the WP at the same time again. I do hope this changes things. But for now, the fan stays for the extra little help my system needs.

  2. #27
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    I can not say what my temps in Fl would be. Every time I have been in Fl I was driving a Ford diesel pulling a gaggle of race cars. I know Ed (Bimmerbum) is in Orlando. His 2.8 coupe holds temp just fine, be it traffic or tracking. Likewise my 3.0 coupe does just fine here in the sweltering swamps of southeast Va. And my two S52 do okay most of the time. It's the other times that I have been playing with the last four years now. But neither has been stock since I've owned them. I started investigating the cooling system because of the oil temps. What I have found is the oil temp starts climbing after the cooling system saturates. You hear it often from the trackers, "the cooling is okay but the oil temps go up". No, it's not okay, the oil temps are climbing because the oil is picking up massive amounts of heat from the head.

    Fan delete is mandatory for me. With the stock fan, these cars sound like a &$$#$% Datsun. Not in my driveway. The fan came off within days of buying my first Roadie.


    You are not stressing the fan any more with the 80C than the 88C switch. You are still wasting the same amount of heat; the delta is the same. The fan will come on for it's first cycle slightly earlier. Again, remember the fan runs full time with the A/C. That means full time for me. My A/C almost never gets turned off.

    Temps. I've been all over the map. I've tried all sort of things. Most didn't make much difference. Some made things worse. The current setup has been promising so far, but the hot months are still coming. Once the oil is to temp (~200F) the coolant is between 78C and 82C no matter the conditions..

    Coolant flow is not linear. Low flow at idle does not mean low flow all of the time. There is an ideal speed for the water pump. Too low and there is no flow. Too fast and it cavitates and flow stalls. The Stewart pump is designed to address the high speed cavitation. What this does to low speed (idle) flow is a mystery. They won't say; I've asked several times/ways. This is why manufacturers are moving to electric water pumps.


    There two problems I have been chasing. One is getting the fan to come on soon enough at idle. The switch should trip before the engine temp climbs. But sometimes it doesn't. This leads to flow issue thoughts. Is the flow low, or is it just taking a route that doesn't flow past the fan switch. Or is taking the low route because the flow is low? Note that the next generation, the E46 and facelift E39s, have the fan switch in the lower hose rather than the opposite end of the cold tank. The other problem is the high speed cooling of the S52. It seems that anything that improves air in, or air out, or more surface area helps. Some more than others. So what is the exact answer?


    /.randy

  3. #28
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    Who has run the lower temp fan switch while running the mechanical fan?

    What temps did you see running this setup?

    My coupe has a fan , and the stock temp fan switch. I’ll be swapping in the lower temp switch, and have been thinking about also running the e36 Diesel fan blades as well as they are less prone to braking.

    Maybe it’s overkill, BMW put it there for some odd reason right?


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  4. #29
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    The thermostat sets the temp of the coolant entering the engine, not the exit temp. It blends recirculated coolant with some cooler coolant from the radiator to achieve the desired temp. As such, you only need the radiator exit temp a few degrees lower than the thermostat temp. As I remember your skateboard is a M52TU, thermostat is nominally 97C. Therefore the 91C fan switch should be plenty. The reasoning for the 80C switch in the S52 is due to the 88C thermostat that we swap for an 80C.


    Short answer, you won't see any difference.


    /.randy

  5. #30
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    Quote Originally Posted by rf900rkw View Post
    The thermostat sets the temp of the coolant entering the engine, not the exit temp. It blends recirculated coolant with some cooler coolant from the radiator to achieve the desired temp. As such, you only need the radiator exit temp a few degrees lower than the thermostat temp. As I remember your skateboard is a M52TU, thermostat is nominally 97C. Therefore the 91C fan switch should be plenty. The reasoning for the 80C switch in the S52 is due to the 88C thermostat that we swap for an 80C.


    Short answer, you won't see any difference.
    Thanks, but my skateboard is Plutonian powered.


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    Last edited by GG///M3; 05-12-2018 at 05:38 PM.
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  6. #31
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    Quote Originally Posted by rf900rkw View Post
    I can not say what my temps in Fl would be. Every time I have been in Fl I was driving a Ford diesel pulling a gaggle of race cars. I know Ed (Bimmerbum) is in Orlando. His 2.8 coupe holds temp just fine, be it traffic or tracking. Likewise my 3.0 coupe does just fine here in the sweltering swamps of southeast Va. And my two S52 do okay most of the time. It's the other times that I have been playing with the last four years now. But neither has been stock since I've owned them. I started investigating the cooling system because of the oil temps. What I have found is the oil temp starts climbing after the cooling system saturates. You hear it often from the trackers, "the cooling is okay but the oil temps go up". No, it's not okay, the oil temps are climbing because the oil is picking up massive amounts of heat from the head.

    Fan delete is mandatory for me. With the stock fan, these cars sound like a &$$#$% Datsun. Not in my driveway. The fan came off within days of buying my first Roadie.


    You are not stressing the fan any more with the 80C than the 88C switch. You are still wasting the same amount of heat; the delta is the same. The fan will come on for it's first cycle slightly earlier. Again, remember the fan runs full time with the A/C. That means full time for me. My A/C almost never gets turned off.

    Temps. I've been all over the map. I've tried all sort of things. Most didn't make much difference. Some made things worse. The current setup has been promising so far, but the hot months are still coming. Once the oil is to temp (~200F) the coolant is between 78C and 82C no matter the conditions..

    Coolant flow is not linear. Low flow at idle does not mean low flow all of the time. There is an ideal speed for the water pump. Too low and there is no flow. Too fast and it cavitates and flow stalls. The Stewart pump is designed to address the high speed cavitation. What this does to low speed (idle) flow is a mystery. They won't say; I've asked several times/ways. This is why manufacturers are moving to electric water pumps.


    There two problems I have been chasing. One is getting the fan to come on soon enough at idle. The switch should trip before the engine temp climbs. But sometimes it doesn't. This leads to flow issue thoughts. Is the flow low, or is it just taking a route that doesn't flow past the fan switch. Or is taking the low route because the flow is low? Note that the next generation, the E46 and facelift E39s, have the fan switch in the lower hose rather than the opposite end of the cold tank. The other problem is the high speed cooling of the S52. It seems that anything that improves air in, or air out, or more surface area helps. Some more than others. So what is the exact answer?
    Excellent answer Randy, thank you so much, truly, and actually I think you just added the final pieces to the puzzle for me. I did not know that the next generation put the temp switch in the lower radiator hose. This tells me exactly what we are seeing was recognized and viewed as a problem and rectified by the engineering department at BMW. It is in a bad spot, which, like you say may be low flow, or taking route around fan switch, path of least resistance, etc. This all makes perfect sense. Has anyone done a mod to put the fan temp switch in the lower radiator hose? I will try to tackle this during summer perhaps. Thank you for this insight.

    I agree that the Fan sounds like a Datsun locked up, funny, or like a 1950's schoolbus as I call it. But yes, loud, annoying, and mildly embarrassing right? I do get it, and see why you immediately removed and placed on the shelf. But for me understanding that we have low flow, or bad placement of switch, or path of least resistance etc, and that that extra airflow for me, at idle, when I need it the most, has a positive effect on cooling the coolant in the radiator on top of bringing fresh air over a hot engine and keeps the overall coolant temperature down, that I can see in real time having an effect, is hard to remove. It is working as intended at this point. I do think the design is flawed. And since the electrical fan is running off the radiator temperature switch, which isn't working correctly it seems, makes it all the more important to have the good old fashion Datsun fan in there, because I can see a real difference with it in and doing its job. Radiator cools the engine, clutch fan helps cool radiator. Car happy.

    I do understand that the electrical fan runs full time with the AC on. This is why I asked for data points with it off if you had them, because if I recall correctly, I read through one of your entire cooling threads to hear you say "I live in FL, I don't know, the AC is always on". I was so disappointed. And when someone asked you for quantifiable data with the clutch fan back on after, it was shrugged off. Those would have been great numbers to have. The base point. Something to judge against. Is this working? Is the clutch fan removal a good idea? As we all know, the electric fan is not controlled by the engine temp, but by the (faulty) fan switch in the radiator, and if the mechanical fan can alter that radiator temp at low speed or idle, to keep everything in check, count me in.

    I and everyone on this forum appreciate that you have been experimenting with radiators and shrouds, and have been amazing in gathering data. And with all your knowledge, in every square inch of these cars, Randy and Randy are king, we all look forward to your advice. You guys are the in house mechanics, and we vastly appreciate and trust you. We do. Especially when new. We may hang a little too much on every word you say actually to our own detriment for better lack of knowledge, or misconstrue your true meaning. And are afraid to ask for clarification perhaps. But, honestly and whole heartedly, thank you for your service and knowledge, it is huge, and appreciated by so many more than you probably even realize. The internet reaches very very far corners of the world.

    For the past three years now I have been monitoring my S52 engine temp every single day starting around May through late Oct. I know my cars behavior now, in every condition. Fan delete scares me watching the temperature swing up until electric fan kicks in, which I agree feels too late. And is which why I really like the lower radiator hose temp switch idea, I feel this would be more in line with actual temperatures entering the engine.

    What is the answer? I agree, I don't know. But I think we can both agree that good old air flow is what we are after. And is why I went to the extent of experimenting with weather stripping out. Massive air flow increase. At speed, it is effectively 100%. Yesterday again, will be cruising 194F (90C) on the freeway in 85-95F ambient air temp, witch is two degrees above 88 Thermostat is opening. It is picking up two degrees heat in the engine head and that's it. Very effective. And yes, oil temperature, aye yie yie, another fun one with the S52 in these cars. I can say this, however, it is much harder to get a precise oil temp reading on my gauge, but, 220-230 now with stripping out. I do believe that this extra airlflow cools the block and metal and all other components under the hood. Heat soak doesn't occur as fast or as much, now the back of the block is being cooled. I used to see 240ish and sometimes mildly higher on the hottest of days. I will have to keep an eye more on the oil temp this summer.

  7. #32
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    I added a switch (180/165 degree) in the lower radiator hose that operates only the aftermarket puller fan. It does seem more responsive. I still have the low-temp switch in the radiator that operates the stock aux fan. I think all these things help , but the mod that has made a serious difference was cutting on the M bumper, shown in another thread. It is a game-changer. We haven't seen 100 ambient yet since I did it, but I can't get the needle to move off of 12:00 no matter how hard I run it: 85 mph for a few miles, then immediately to a stop. I still won't fully trust it until I see it work at 115 ambient, climbing out of the valley.

  8. #33
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    Quote Originally Posted by zellamay View Post
    I added a switch (180/165 degree) in the lower radiator hose that operates only the aftermarket puller fan. It does seem more responsive. I still have the low-temp switch in the radiator that operates the stock aux fan. I think all these things help , but the mod that has made a serious difference was cutting on the M bumper, shown in another thread. It is a game-changer. We haven't seen 100 ambient yet since I did it, but I can't get the needle to move off of 12:00 no matter how hard I run it: 85 mph for a few miles, then immediately to a stop. I still won't fully trust it until I see it work at 115 ambient, climbing out of the valley.
    Link to said thread?


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  9. #34
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    Zellamay, I saw what you did with the front bumper for better air flow, amazing!! I couldn't believe it when I saw that photo of the orange 12 cylinder with the exact same bumper trimmings. Pro job, you obviously are on to something there! So glad it has helped in keeping your temperatures down. Good to know, thank you. Heck if i was in Arizona, I might consider an entire hood delete I think!

    On your 180/165 degree F switch to puller fan, just out of curiosity, how often does it seem to cycle? (If you can even hear it in cabin or tell), and what is the OBD2 readout at that point? It would be interesting to know. I would think puller fan would be on pretty consistently, but if not, possibly our radiators are doing a dynamite job and a little better than we are giving them credit for (but I doubt it.....). Did you buy a hose with the temperature switch/hole location for the later e46 models, or just drill baby drill? I'll have to search for a pic of the e46 setup......

    And, if you don't mind, at what temp can you read on your OBD2 (if applicable) when your traditional BMW electric fan kicks on at? I know that that temperature doesn't actually control the fan, but I want to know the spread, the delay, the low flow so to speak. My 91 degree radiator fan switch is kicking on right around 100C (212F on OBD reading right after trip through the head, before it goes back into the radiator {if I have that right, full disclosure I may not}), a 9C (17F) spread difference, and actually, seems possibly logical to me to expect a radiator can and will cool this amount but I have no other data points and never ever have taken it this far in another vehicle (nor do I care to at this point, one's enough, ha!)

  10. #35
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    I bought the parts below, cut the right amount out of the middle of the lower hose (measured the part, around 2"), and wired it directly from the fuse box. It has 12V available all the time, so it runs about 90 seconds after I turn the car off in 100 degree weather. Interesting: sometimes it is not running when I turn the engine off, but then starts running about 20-30 seconds later. So, when airflow stops, the engine heat, either through the air or through the water, is raising the temp in the lower hose, causing it to go on. That's okay, just noting it. ... I don't know how to read OBD2 temp. I have the INPA on a laptop, but don't know whether I could use that. You can tell I'm not a computer guy. I can say the the aftermarket fan comes on when the stock aux fan does not come on, probably because it's run by the inline switch which is a (lower-temp and better located) switch. I used to have the situation rf described, where the fan doesn't come on soon enough when idling. The inline switch seems to fix that.
    .https://www.amazon.com/Upgr8-Aluminu.../dp/B00FY2LWII
    .https://www.amazon.com/dp/B079633F11...ing=UTF8&psc=1

    - - - Updated - - -

    Quote Originally Posted by GG///M3 View Post
    Link to said thread?


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    here it is. It's now just down a few from this thread, called "M Roadster bumper mod for air flow

    https://www.bimmerforums.com/forum/showthread.php?2376096-M-Roadster-bumper-mod-for-air-flow

  11. #36
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    Nice!! Thank you so much for the link, I like your set up, may copy it. Don't worry about the computer thing at all. You seem like you are doing very well, heck, you've got INPA on a computer, I am jealous. I need to take that step as well, you've got me beat. I'm pretty sure you can check temps, but that involves taking your laptop for a ride and a pain. No worries on not having OBD2 dongle capabilities. It just would of been interesting info and given me a good reference point to go off of. Quite possibly someone else with a similar set up/spal can chime in and say what, on an S52, does the OBD2 read out say when a specific temperature point is reached on that lower hose and mark the difference. It would better tell us what the true temp in vs temp out would be, and how much the radiator actually cooled the coolant in between.

  12. #37
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    [QUOTE=zellamay;30021342]I bought the parts below,

    .https://www.amazon.com/Upgr8-Aluminu.../dp/B00FY2LWII
    .https://www.amazon.com/dp/B079633F11...ing=UTF8&psc=1

    - - - Updated - - -

    Zellamay, did you order the 28mm as in your link, or was that just an example of the part? I'm looking to order the aluminum temp sensor adaptor but unsure of the inner diameter of the lower hose. Gmusial in another thread said 32mm on his M52. I believe we share the same hose according to real oem..... http://www.realoem.com/bmw/enUS/part...6988&series=Z3

    But I could have that wrong.

    Thanks!
    KJ

  13. #38
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    No, I actually bought the 38 mm, not sure why the link reverts to the smallest size. There's another current thread that will address your question. Bottom line is : measure yours.: https://www.bimmerforums.com/forum/s...inner-diameter

  14. #39
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    Got it, thanks again for all your help Zellemay!

  15. #40
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    This may be dumbe question. But would heat extractors on the hood help. I swore I seen a fiberglass good with vents on the side.

  16. #41
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    Quote Originally Posted by ShelbyGT500 View Post
    This may be dumbe question. But would heat extractors on the hood help. I swore I seen a fiberglass good with vents on the side.
    This is actually such a logical question that it is kinda comical talking about taking out weather striping and such. No, you are 100% right, this would be the pro way to go, all the way. Top of the hood as well as the sides I believe would be beneficial. I would worry about rain in the winter time and what lies below the slats (if on top, side vents not so much), but for many these are track or summer toys only anyway. I have merely just been playing around with engine temps and seeing what the effect of a little extra airflow under the hood provided on coolant temps.

    My conclusion, is that I re-invented the wheel This is why you often see heat extractors on a race track, they work. And water concerns, is why it doesn't cross over to the everyday design.

  17. #42
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    I am reminded of a quote from Colin Chapman, where he was asked about the popularity of Austin 7 based racing classes. To paraphrase, he said that the cars were so bad that ANYTHING you did made them fater. Everyone could be a tuner.

    I think this applies to the natural airflow of the S52 engine bay, as well. I am really looking at making the side gills functional. If engine bay air will flow into the high pressure zone at the base of the windshield (removing the weather strip), you know there's a lot of trapped air.


    /.randy

  18. #43
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    Randy- Do a write up on the side vents? I would love to read it.

  19. #44
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    I wonder if a small chin spoiler of sorts could be used to redirect some air from going underneath the car.
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  20. #45
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    How about this set up....

    https://www.protuninglab.com/ra-bmw-...d=140852203018

    seems pretty cheap too. With aluminum expansion tank, etc., seems like it would durable and the fans would keep things cool after a mechanical fan delete...

    any one use one of these?

    Greg
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  21. #46
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    Three row Chinese radiator. I tried one. Was leaking in a year. And the fan mounting is as close to useless as you can get. I it three fails.


    /.randy

  22. #47
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    Thanks Randy. Figures.

    Greg

  23. #48
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    Quote Originally Posted by rf900rkw View Post
    There two problems I have been chasing. One is getting the fan to come on soon enough at idle. The switch should trip before the engine temp climbs. But sometimes it doesn't.
    Randy did I ever share with you the Dinan vacuum pressure switch that kicks the fan on at 4 Lbs. of boost?
    Built S52 w/Dinan ISR-3 kit, NickG Stage 2+ Tune, Dinan Vortech V2 Supercharger, Dinan Air to Air Intercooler, Dinan CAI, Porsche 803 HFM, Buldogge 6" crank pulley, Griptec 2.90" blower pulley, Eurosport UD pulleys, Dinan 3.38 Diff, Dinan front/rear Swaybars, Dinan springs, Koni Yellow Sport Struts, Ground Control end links, South Bend Clutch Stage 3 Organic, AASCO Light Weight Flywheel 18.5#, Zionsville Radiator & Oil Cooler, Riot Racing BBTB, Schrick Intake Manifold, 42# Injectors, Schrick cams 264/256, Forged Wiseco pistons 9.0 comp., Forged Eagle rods, Supertech dual valve springs & valves, VAC crank & bearings, Supersprint mufflers, Euro Z3 midpipe, Raceland euro headers, Walbro 255, Bevauto ignition coils, Vortech Mondo bypass, Bailey Diverter DV30, Ireland Rear Subframe Bushings, Mason Engineering Strut Brace, Mason Engineering Clutch Petal, Apex 18" EC-7 Wheels, Full Custom Sound System, two trunk lids (with & without OE spoiler), Hardtop, Trunk full of AK's...

  24. #49
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    Quote Originally Posted by KJ79 View Post
    Greg, I would like to hear from other S52 owners as well who have done the fan delete and are using real time temps from OBD2, not the dummy gauge in the dash, because I too have seen your exact scenario as described above to my dismay. Its not all the time, but under enough stress in the warmer weather, I have seen your exact numbers. My electrical fan kicks in at 212-214F as well.

    Car is absolutely fine when moving without mechanical fan, it is in warmer weather stop and go, coming off the freeway, or under a prolonged load at lower speeds, like taking my long twisting one lane road home for 1/2 mile. Very little airflow, 35% incline. Tons of load. Disaster.

    To me, and some may say these numbers are fine and arbitrary, it is too close to a problem for my comfort and one electrical mishap away form a run away train. Now I could wire a spal, figure all that out with diagrams and such and shroud fittings, and still not have it pull as much air as the stock setup from what I can read. I'm not going to lie, I am very worried about the fan seizing, exploding, taking out a few hoses and quite possibly put a dent in my hood. But, my hood actually has a very slight dent in the nose already (bought it that way), and hoses, radiator, expansion tank, etc.....those are things I can fix. That's a Saturday. What I can't fix, is a melted head. And a blown head gasket. And I have know clue how to mill down a block, and take it all apart and put humpty dumpty back together again. And I could learn, sure, but, at heart I am an enthusiast, not a die hard mechanic, and that is a project I truly wish to never have to tackle.

    So I reached into my trunk, put my mechanical fan back on, and was immediately back to my usual topping out at 206-207F. Electric fan never even comes on with mechanical in there. It doesn't need to. It is the back up, not the primary. And per my other thread commenting on weather stripping being taken out, I can have that number down to 199F in the same conditions. She breathes. And for me, those 15 degrees or so is nothing to shake a stick at, is unnecessary heat on the entire engine compartment, and adding pressure buildup on an already aging and frail plastic system.

    I check my mechanical fan every couple of weeks to make sure it is in good working order, and I monitor my temps almost daily this time of year. We are cool as a cucumber, and that is truly what I am after.

    Some will say just add a lower temperature switch in the radiator. And this is a good option for keeping temps cooler and that fan kicking on sooner, but, there's pros and cons to every compromise and that is putting extra stress and work on the electrical fan. I think what it comes down to most, is do what you feel most comfortable with. That is how you will be happiest. And that is what your M is all about.......
    Although I didn't record the exact numbers as you have, I had nominally the same experience with my S52. Following the advice of many on this forum, I had performed a fan delete. As soon as summer arrived in Georgia, I found my oil temps running high. I decided to check coolant temp with an ODB app. The temps were too close to calamity for my taste. I bought a new fan to delay the possible catastrophic fan failure and reinstalled the mechanical fan. After that I monitored the coolant temps long enough to convince myself I had some safety margin for all driving conditions I experience - no track driving or long-duration high load driving and I seldom drive in stop and go traffic.

  25. #50
    Join Date
    Aug 2014
    Location
    Northern CA
    Posts
    212
    My Cars
    1999 M Roadster
    Quote Originally Posted by rf900rkw View Post
    I am reminded of a quote from Colin Chapman, where he was asked about the popularity of Austin 7 based racing classes. To paraphrase, he said that the cars were so bad that ANYTHING you did made them fater. Everyone could be a tuner.

    I think this applies to the natural airflow of the S52 engine bay, as well. I am really looking at making the side gills functional. If engine bay air will flow into the high pressure zone at the base of the windshield (removing the weather strip), you know there's a lot of trapped air.
    This is funny Randy, I 100% agree!

    I was thinking about installing this fan under the hood, anyone tired it before, no reviews? ...... https://www.amazon.com/O2COOL-Licens...70_&dpSrc=srch

    Quote Originally Posted by JustinHalverson View Post
    Although I didn't record the exact numbers as you have, I had nominally the same experience with my S52. Following the advice of many on this forum, I had performed a fan delete. As soon as summer arrived in Georgia, I found my oil temps running high. I decided to check coolant temp with an ODB app. The temps were too close to calamity for my taste. I bought a new fan to delay the possible catastrophic fan failure and reinstalled the mechanical fan. After that I monitored the coolant temps long enough to convince myself I had some safety margin for all driving conditions I experience - no track driving or long-duration high load driving and I seldom drive in stop and go traffic.
    It sounds like our S52 cooling systems are operating in almost the same manner in stock form, thank you for your input and chiming in. It will be very interesting to see what happens when the radiator fan switch location is changed to the lower radiator hose when I am able to tackle it next month. Low flow, or bad temperature switch placement in general, hopefully it can shed some light and good info on the situation.

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