Miata running hot.. Need help and advice please

Some of the specifics- 92 miata 170k temp guage sitting around 1 o'clock on the guage, 1 yr old factory radiator and cap, recently flushed and 50/50 ratio, thermo switch checked and functioning, both fans working properly, removed coolant return hose to block to check water pump=good flow,new mazda thermostat, no leaks and i don't have to add any coolant, and lastly did compression check today and all cylinders to verify head gasket and it checked out great with no air bubbles in the coolant... have I missed anything.. pls advice.. any local shops you guys would recommend to diagnose and fix??? thanks for the help MIATA friends

I'd sell that car as fast as you can!

The mixture isn't 50/50 we did put some distilled water in it. ;)

I'm thinking it's the water pump since it is the only item the previous owner didn't replace.

There is some more good stuff to check.

Miata Solutions is the best there is for a local shop!

I am not sure this is the fix ... but ... my 99 was runing a little wramer than usual last week in the Dallas downtown stop-n-go traffic. I am due for an oil change. After I changed the oil, the needle of temp gauge barely move even in today 103F and driven hard.

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Originally Posted by POS Racing

There is some more good stuff to check.

Miata Solutions is the best there is for a local shop!

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Thanks for the links POS. I have actually been reading up on those links for a few days now. getting frustrated.. just want it to run normal::Censor::
BTW you have a pm

Thanks for heads up gab.. i believe i still have about 2k left before i have to change out the oil.

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Originally Posted by POS Racing

I'm thinking it's the water pump since it is the only item the previous owner didn't replace.

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How scientific was your test?? The water pump is the only item that that was not replaced by the previous owners. So the possibiliy is high that that is the original 170,000 mile water pump. ::Blink::

Have you switched back to the OEM intake setup or are you still drawing air directly next to the exhaust manifold??

POS 2's intake is back to stock form and also checked timing and it was at 11

Check your PM's! ;)

Anyone know what are the signs of a failing H20 pump??

Generally they leak at the shaft. Impellers could disintegrate but that would be a rare occurrance and should put rust crap in the coolant.

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Originally Posted by channelmaniac

Generally they leak at the shaft. Impellers could disintegrate but that would be a rare occurrence and should put rust crap in the coolant.

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hhmmm never saw any icky crap in the old radiator, but with a 170,000 miles on it ya gotta wonder how much of the impeller is still around.

Some History:
Radiator, Radiator Cap, Thermostat and all Hoses replaced July 2005
All88 Replaced the thermostat on Friday with an OEM part.
I also recall All88 telling me he replaced a belt or two not that long ago.

Any front teeth added?

What about the A/C system?
Is it cycling normally?

Just thinking about some other things that could influence the engine temps.

This time a year 220+ is common and nothing th threat about, however is it getting hotter while on the highway or just idleing?

We had a customer's car that kept increasing in temperature only when we were testing on the highway. As soon as you slowed back down the tempertures would drop. Turned out to be a clogged radiator. With higher flow at higher RPM the efficiency went down due to reduced cooling channels.

Also if this car at one time was low on water and was sitting exposing the cast iron block to air, this would cause oxidizing leaving rusty particles to clog up a few radiator runners. If you want to test another radiator we have a couple.

We are pulling a double core radiator out of a customer car tonight to replace it with our PWR radiator and a TDR intercooler and is for sale for $50. we know it works just fine.

I have not seen a water pump fail partially, they either work or they don't. Give us a call if you want it 214-280-6172.

Gary

My water pump was leaking. I had it replaced and then the temp would rise only if the AC was on and I was at hiway speeds. Sitting in line at the bank with the AC on was never a problem.
Problem was diagnosed as clogged radiator. I replaced the radiator Saturday and gave it an extensive test around noon. It ran fine.
I'd take TrackDog's offer and try a different radiator. Took me less than 2 hours with sammm's help to swap and it was my first attempt.

I'd also suggest 60% water / 40% coolant.

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Originally Posted by onething

I'd also suggest 60% water / 40% coolant.

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That was going to be my first suggestion. Its the easiest to try too.

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Originally Posted by POS Racing

Check your PM's! ;)

Anyone know what are the signs of a failing H20 pump??

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Yea, it leaks.

I can't imagine it being the orginal with that many miles, most (not all) are replaced with the timing belt, and the car's got enough miles it should have had at least one, possibly two Timing belt changes.

I too have been having high temps, this last week. I'm running between 102c and 106c on the highway. I've been experimenting with different things to get more air through the radiator, and they have helped, as the temps I'm currently running, I was running when the daily high's were still in the low 90's.

I'm also running 25/75 antifreeze/water ratio.

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Originally Posted by general default

Any front teeth added?

What about the A/C system?
Is it cycling normally?

Just thinking about some other things that could influence the engine temps.

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hey general. no blockage at all... ac works just fine..:confused:

I'd also suggest 60% water / 40% coolant.[/QUOTE]



Thanks for the feedback guys. how do measure the ratio/ how much coolant does the miata hold? seems like it works for a lot of folks...

had a chance to talk to trackdog this afternoon.. trying to work around my work schedule to be able to see him... i am so tired of turning on the heater to lower the temp down to normal

a quick question to M1 owners please. where does your factory temp guage sit when your car is running a little hot when it's 100 degrees or more...- what's "normal" hot for the miata? any range after mid point to "H" ? is that considered normal hot? thanks for your feedback.

Flyin Miata uses 70% h2o 30% antifreeze, changing the ratio has helped at least 3 M1's run cooler...

The radiator holds right at 1 gallon of fluid. 'Normal' operating temperature on the gauge is just left (on the cooler side) of the mid-point. Don't forget to use distilled water. DO NOT use your garden hose!

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Don't forget to use distilled water. DO NOT use your garden hose!

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Mineral water is better. Since it has tinny mineral fragments of minerals which have better conductivity, hence your radiator runs more efficient ::Clown::

Got some real great feedback today from the forum. Trackdog,Samm, Sharpie, POS,Steven from Miata solutions, and the rest of the dfw miata crew...POS actually helped me change the ratio of my anti freeze (your a great pal!:thumrigh:) and added an additional additive cooler recommended by Steven
I'll keep you guys posted on the outcome tomorrow.

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Originally Posted by ALL88

I'll keep you guys posted on the outcome tomorrow.

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Well it is now tomorrow. ;)

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Originally Posted by POS Racing

Well it is now tomorrow. ;)

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Perhaps ALL88 is too busy driving his cool car to get online.

hello friends... got some feedback... Definately ran cooler than normal even at 106 degrees. highway was fine but right when i got stuck on stop and go trafic at cooper on my way to a meeting the temp started rising and never recovered until i turned on the heater :( i can see the that the temp guage stays just a touch below the halfway mark (normal temp)for a little bit and BOOM::Flame:: and then moves ever so slightly to the middle and rises tp 2 o clock and has a hard time recovering.. the search for the solution continues....

How high did it rise??

I'd defiantly consider the radiator Gary has if it is a larger capacity than the OEM one that is in the car now. From all the test you have run I'm beginning to think the OEM radiator just isn't going to do it once the ambient temperatures exceed 100 degrees.

See what it does once the temp drops below 100 outside.

I read the thread the other day, and I think you said the fans are working. Are you sure they are turning at full speed? All the overheating problems we have seen while the car is at speed has been a clogged rad. The car overheating at a light would say to me fans. BTW My car didnt overheat at all sitting in traffic this afternoon, so it should be able to handle it.

Cool write up on the Miata temp gauge.

http://www.gravitydesign.net/saturn/...BothSweeps.jpg

less anti-freeze, more water.

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Originally Posted by mr brg

less anti-freeze, more water.

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I think he tried that.

Well Sparky what did you figure out???