Page 1 of 2 12 LastLast
Results 1 to 20 of 33

Thread: Miata Cooling Design Question/Issue

  1. #1

    Default Miata Cooling Design Question/Issue

    Just picked up a 97 NA8 with 135K on the clock. I thoroughly test drove the car and saw everything was in order. Previous owner had replaced all major hoses and the fans. Radiator had no "burnt" look. Coolant was nice and green and clean. But when I started doing AutoX-ish maneuvers for about 5 minutes in a parking lot, the temperature gauge started to rise and get close to the H. I stopped, turned heat on, and let the car idle and it returned to normal. No problem.

    I've read our radiators have horrible design. I know many buy the aftermarket Koyorad's or switch to some crazy duty 37mm or 39 mm or even 55mm all aluminum radiators. But everything I read says that is only needed for miata's with forced induction and track duty.

    I figured I'd just drain my radiator and refill with distilled water. Did so, burped system of air, all good and gauge stays at 11 o clock. moved to 1 o clock after some vigorous parking lot maneuvers but obviously much better than before.

    So the question is, with my power output being stock, and increased cooling of my watered down cooling system, do I need to really worry about doing AutoX in this damned insane Tx Heat? Obviously I'll watch the gauge but I'd rather just drive more and worry less.

    Also, I typically run the car with the AC on, so that both fans are on, helping out cooling I believe.

    Do I need to do anything else to the stock cooling system? Or should I upgrade since this is my nominal street car with an emphasis on heavy future AutoX and Track Use?

  2. #2

    Default

    The radiators in these cars (and any modern car) are not a lifetime part. If you don't know the service history a new radiator may not be a bad plan.

    My 2002 with 106,000 miles that I bought new is on now on its second radiator it was under $150.00 for a replacement OEM style radiator. I have tracked it and AX'd it for years.

    Thing is when the radiator fails your odds of spending serious $$$ to fix your baked motor increases exponentially.

  3. #3

    Default

    It's actually like 80$ off amazon for a TYC. (even more reason to replace, right?! Ha)
    I know these are to be replaced, but like I said, the system looks so new. And the coolant is also brand new. No reason to believe the seller lied when he said he went through it all, based on my thorough checks. I was thinking a thermostat replacement wouldn't hurt either.

    If I have issues this next Saturday, both parts will be yanked and replaced.

    Any other cooling tips?

  4. #4

    Default

    The fluid may be new now but what was in it just before it was changed? Just changing the coolant does not normally get all the old crap out of the coolant system, but it does make the coolant look new.

    The key part of the cooling system for removing the heat from the engine is the radiator. So if the car is getting hot I tend to question the condition of the radiator. Seems logical to me but what do I know.

  5. #5

    Default

    No no, you make sense. I haven't had a repeat since I first got it and I drive hard, so maybe that's why I'm nonchalant. But I was thinking the radiator is next on the list.

    I feel that the designers did not anticipate the miata being thrown around in 95 degree heat, 2nd gear, with not alot of speed and air flow through the radiator. So that's why I was curious if the OEM system is up. For the job. Which it seems to be.

    So another question. If the needle is creeping towards H, I should stop, but leave the car idling and so keep the water pump working, but if it hits H, I should turn it off, correct?
    Last edited by Yamahaman444; 07-10-2016 at 01:13 PM.

  6. #6

    Default

    Quote Originally Posted by Yamahaman444 View Post
    So another question. If the needle is creeping towards H, I should stop, but leave the car idling and so keep the water pump working, but if it hits H, I should turn it off, correct?
    The more air you can force in the nose the better IMHO. But yea if your headed towards H I'd stop.

    You have the under-tray and all the aerodynamic do-dads that Mazda bolted on these cars back in Hiroshima??

  7. #7

    Default

    No undertray. I read it helps with airflow especially at lower speeds, correct?

  8. #8
    Chassis Designer Ziggo's Avatar
    Join Date
    Jul 2014
    Location
    Melissa, TX
    Posts
    79

    Default

    It helps at all speeds

  9. #9

    Default

    Well dang. All I gave left from Japan is those super sweet shipping anchors.

  10. #10

    Default

    1. Get an under tray $65 + shipping - don't drive the car without one! - (anybody have the link for the Rosenthals replacement?)
    2. Get a new thermostat $7 - I use a 180o Super Stant from NAPA - http://blog.miataracer.com/2014/01/s...pec-miata.html
    3. Get a new radiator cap $12 - a Stant from NAPA works.
    4. Replace your coolant with:
    a. $10? - a 20% coolant (anti-freeze), 80% distilled water - coolant (anti-freeze) protects from freezing and corrosion but doesn't cool well. Water cools better! 50/50 mix will overheat for AutoX/Track.
    b. $10? - or distilled water and RedLine Water Wetter (not Purple Ice), you'll need to either keep the car in a garage from Oct to March or put some anti-freeze in for winter. Purple Ice will not protect from corrosion with distilled water, ask me how I know.

    If these don't work think about:
    1. The water pump. How old is the timing belt? There maybe a date on it. If it looks old, change it, the water pump, cam seals, front seals, idler pulleys and valve cover gasket. Gates makes good replacements. Trackdog has a kit.
    2. A new aluminum radiator - either a stock one or a CSF. It is big, not too expensive and available at either 949 Racing or Goodwin - http://949racing.com/CSF-radiator-miata.aspx

    If you really want to spend some money unnecessarily, you can install a re-route: http://www.miataturbo.net/race-prep-...-thread-79930/
    '99 Emerald Green - 2015 NASA Texas TTE Season Champion (showing up is really 100% of it)

  11. #11
    Mr Miata Solutions Rogue's Avatar
    Join Date
    Feb 2007
    Location
    Propwash 16Xray
    Posts
    2,560

    Default

    Pressure test it…...If its not holding pressure, you can throw fancy parts at it all you want.
    OEM parts are fine for a stock NA Miata, plenty of them running with no issues.
    I use 33% coolant (1 gal of real coolant and 2 gal distilled water)
    I also replace the cap with a uprated lever cap.

    Eric, Rosenthal doesn't exist anymore…..Tommy's at Priority Mazda now.

  12. #12

    Default

    Quote Originally Posted by Rogue View Post
    OEM parts are fine for a stock NA Miata, plenty of them running with no issues.
    +1

    I drive mine very hard on the track and AX and have no issues with my OEM setup.

  13. #13
    Orange cones fear me. cone-cerned's Avatar
    Join Date
    Dec 2005
    Location
    Woodbine, Texas
    Posts
    4,676

    Default

    Quote Originally Posted by Rogue View Post
    OEM parts are fine for a stock NA Miata, plenty of them running with no issues.
    Quote Originally Posted by jrj512 View Post
    +1

    I drive mine very hard on the track and AX and have no issues with my OEM setup.
    +1
    On the track, I am fearless.
    If you were as slow as me, you wouldn't be afraid either.

    1994 M Edition
    CSP 67

  14. #14
    Team Cheap Bastard
    President & Founder
    sammm's Avatar
    Join Date
    Jan 2004
    Location
    NC
    Posts
    6,438

    Default

    +2...and I've run for weeks, autocross included (gasp!) without a belly pan.

  15. #15

    Default

    I had read about the 50/50 not cutting it and since I drained and refilled the radiator with distilled water, I have not had an issue.

    I just wanted someone to chime in and confirm that OEM can handle this ridiculous heat

    At least I didn't start an oil thread

  16. #16
    Team Cheap Bastard
    President & Founder
    sammm's Avatar
    Join Date
    Jan 2004
    Location
    NC
    Posts
    6,438

    Default

    ^If you go all distilled, don't forget to add some antifreeze before winter.

  17. #17

    Default

    Quote Originally Posted by Yamahaman444 View Post
    At least I didn't start an oil thread
    Or worse, oil filters.

  18. #18

    Default

    Wait. Synthetic or Dino? Hahahahahahaha

  19. #19
    Chassis Designer Ziggo's Avatar
    Join Date
    Jul 2014
    Location
    Melissa, TX
    Posts
    79

    Default

    I didn't realize replacement bellypans were only $65 Ive been running without as well, with plans to craft one (with attachment points for a splitter) once things cool down a bit. At that price it would just be easier to purchase.

  20. #20

    Default

    Quote Originally Posted by Yamahaman444 View Post
    Wait. Synthetic or Dino? Hahahahahahaha
    Dino oil and synthetic antifreeze, FTW!

    B.

Page 1 of 2 12 LastLast

Similar Threads

  1. Miata Journal, First Issue
    By gabkwong in forum Bull
    Replies: 0
    Last Post: 05-14-2010, 04:46 PM
  2. Replies: 8
    Last Post: 04-15-2010, 04:30 PM
  3. WTB Miata Suspension for a Senior Design
    By mk_slayr in forum dfwMiata.com Classifieds
    Replies: 2
    Last Post: 01-27-2010, 04:11 PM
  4. Cooling hoses 93 Miata
    By ken o in forum dfwMiata.com Classifieds
    Replies: 1
    Last Post: 02-26-2008, 02:17 PM
  5. Just a random cooling question
    By trickyrix in forum Miata Tech and Chat
    Replies: 5
    Last Post: 02-26-2008, 09:34 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •