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Car overheated again. This time with no thermostat. Wtf is wrong ?

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Old 07-22-05, 03:28 PM
  #26  
Rotary Power

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Originally Posted by iceblue
Best TS is OEM :-/
E-fan should really only be considered if the clutch fan is dead or you need the room for some other mod. The clutch fan works spectacularly. You can also run into an issue of stock ALT not creating enough AMPS to run the E-fan and thus draining your batt.

On a side note the noise you were hearing from the tranny is a damaged clutch release bearing.

Sorry you have so many troubles, though it is conceivable when building a once non running car into a beautiful running car.
the bearing is new unless it was defective when i put it in or it got damaged after being put in somehow
Old 07-22-05, 03:34 PM
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lol ok, im wrong, search on here in some evans coolant threads and some more threads about removing the TS, i think maybe even evans has a FAQ about it on their site, but i dont remember, without a TS, or TS housing like mazdaspeed suggested to restrict flow somewhat, the flow is too fast to absorb heat INSIDE the engine by the rotor housings where combustion takes place, therefore making higher hot spot temps on that part of the housing and reducing efficiency of combustion, along with some more things, and weaing out the coolant seals more because they heat up more.

at no time did i say the water temp gets hot, i had an 86 n/a without a TS for almost 2 years before someone told me i was hurting the car more by having it out, without the TS my car never showed over 1/4 on the gauge, even in racing conditions. i never said the heat gauge will rise, but the temp inside will be higher.

do what you like, its your loss when you ruin something.
Old 07-22-05, 03:53 PM
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Okay.. Let's not turn this into a TS/Non TS thread. There's tons of them out there, even I have been responsible for one of the debates. Its obvious that he's goign to be running a TS, and it won't blow his engine to test for a few weeks/months without it. Let's solve the problem.

1st thing - testing a TS is easy. Get a pot of water, a stove, and a thermostat that reads up to boiling. Insert TS in pot of water, as well as thermostat, watch what happens as temp gets up to 160 (or 180, depending on your tstat).

2nd thing - Are you getting coolant boiling/bursting out of your overflow tank? Has your overflow tank changed its status at all? It sounds to me like you might have some air in your system still.. try this: next time you have the TS neck removed, fill up the block as fara s you can. Squeeze/massage the lower radiator line to make sure most of the bubbles are removed from your system. After you put on the TS neck, BE SURE to remove the top plug from your radiator, when you're filling in the rest of the coolant. When you run the car afterwards, remember to have the heater on the car on full blast on the hottest setting.

IceBlue - The radiator should be easy to check for severe blocks: Next time you drain the system, undo the 4 (6?) bolts that hold the radiator on. Once its out of the car, simply take a couple gallons of water, see if they pour out of the radiator at roughly the same rate as its filled. To do a thorough test, i think you have to take it to a radiator shop, though. This should allow you to at least make sure that water is flowing through the radiator.
Old 07-22-05, 04:00 PM
  #29  
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Evans NPG+ is a special waterless coolant with a 375 degree F boiling point at zero psi and does not freeze until -70 degrees F (it contracts and gets 'slushy'; not really freezes). Because it is non-aqueous (no water), corrosion is virtually eliminated and there is no need to change it yearly. In fact, it has been tested for hundreds of thousands of miles with no signs of degradation, according to Evans. While the initial cost is high, compared to ordinary coolant, it is a bargain over the life of the vehicle. Ordinary coolants operate at the verge of boiling, which puts them at high risk of localized boiling at hot-spots within the engine, even when coolant temps otherwise appear moderate. Any localized boiling interrupts heat transfer and potentially creates a cycle that leads to overheating (hot spot gets hotter and hotter, until it gets out of hand). Ordinary coolants also require the system to be highly pressurized to raise the boiling point to the required operational temperature. This puts stress on all the cooling system (seals, hoses, etc.) and poses an additional risk of a leak that depressurizes the system and drops the boiling point of the coolant below operational temperatures. Evans NPG+ coolant, on the other hand, can be run at zero pressure and has a remarkably high boiling point of 375 degrees F. Because its boiling point is so high, localized boiling is eliminated and overall heat transfer is greatly improved. What you will notice is (1) your vehicle will get up to operational temperature in about half the time, (2) it will then stay right in the optimum temperature zone even when driven well beyond what ordinary coolants could endure. We have found that most cooling problems in RX-7s are due to overtaxing the coolant, rather than other components of the system, like the radiator. Upgrading to a big aluminum radiator is not usually necessary with Evans NPG+, because the stock radiator becomes more effective using a coolant that better transfers heat. Evans NPG+ is far more cost effective than a new radiator!


www.evanscooling.com

read some of the faq's and info on heat transfer on evans' site.

Last edited by Agent_D; 07-22-05 at 04:05 PM.
Old 07-22-05, 04:06 PM
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Sounds like good stuff.. But there's no price listed at all.
Old 07-22-05, 04:18 PM
  #31  
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its like 35$/gal you can buy it from corksport
Old 07-22-05, 04:21 PM
  #32  
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I just went over my entire cooling system because in AZ we're hitting 110+ temps.

My car would run around 210 during the day and start creeping towards 220 if on the highway(constant load).

I replaced my thermostat. Did nothing.
I then bought new fan belts and took a S5 clutch fan.
I installed it and the temps instantly dropped to 195-200 during day and 200-208 highway.

I think my belts just got old. The part which grips hadb a shine to it so I figure it was slipping. I changed the Fan just as a precation(S5's actually have more fan blades than S4's/not sure if it performs better).

So.

-Check the Tstat
-Check/replace your Belts(it's cheap! so just do it!)
-Make sure you have a dual pulley if no Airpump
-Check fan/replace if you have a spare or can pick one up from Junkyard
-Get your radiator tested/cleaned
-Replace water pump.

If all that doesn't work then I'd almost say your engine may have a coolant seal problem and is causing over heating that way.

Also for $60 yo can go buy an Autometer Temp guage so you can tell the REAL range your running.
Old 07-22-05, 04:24 PM
  #33  
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Oh I also forgot to ask if you've noticed any leaks?

If you have a leak the car will not pressurize and it will pump the coolant out of the car and over heat since the coolant will boil instead of cooling under pressure.
Old 07-23-05, 12:43 AM
  #34  
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Why on earth are we telling a dood to try evans that is having cooling issues?
Here go spend $80 on this coolant and maybe it will solve your issue. Hope you don’t have to drain it and possibly lose some. After you spent 45min cleaning out the system to use evans. There is no reason his car should not run proper on water and anti freeze. After your issue is fixed and you want to run evans by all means go for it. But to use it now would be foolish.

Last edited by iceblue; 07-23-05 at 12:46 AM.
Old 07-23-05, 01:55 AM
  #35  
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lol i never told him to switch, i just said evans would be a good move, lifetime coolant with no changing ever, 0 pressure, infinitely better heat soaking
Old 07-23-05, 08:23 AM
  #36  
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Originally Posted by Agent_D
lol i never told him to switch, i just said evans would be a good move, lifetime coolant with no changing ever, 0 pressure, infinitely better heat soaking

ill look into it , but i fixed the problem for now. i put in my ts (i found out its rated at 180), and now the car runs and drives fine...i shut it off and it was kind of hot and water was going into the overflow but it was not overheating by anymeans so it should be fine now

i bled the system and topped off the coolant

id like for it to run cooler so i may look into gettting that evans stuff
Old 07-23-05, 12:49 PM
  #37  
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getting evans doesnt necesarrily mean when you look at the coolant temp gauge that its gonna be lower than with coolant, but the cool with water/glycol mix has a boiling point of, i think, 260ş pressured at 13lbs, correct me if im wrong i dont remember for sure, like our stock caps have, the boiling point of evans is 375ş, so for evans a water temp sensor with numbers would be better than looking at the stock gauge, cause it may show a higher temp on the stock gauge then with water/glycol, but it wont be overheating cause, if memory serves right, the stock temp gauge only shows up to 260?? again correct me if im wrong.
Old 07-23-05, 02:02 PM
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The only real benefit is a low to no pressure system. It will not make your car run cooler. Your car must run between 180 200F. The TS regulates this. A colder engine will be just as insufficient as a hot engine.
Old 07-23-05, 02:26 PM
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as far as I know moving coolant 'too quickly' through a motor will not cause overheating, it will simply be inefficient. And I mean as a result of too high a pump speed, you're just wasting energy turning it faster (pumping water faster) than necessary.

As for the thermostat, you want to run a thermostat because it provides a necessary restriction in the coolant system. This is not to slow down the flow, it is to increase the coolant pressure behind the thermostat caused by the pump. Without a thermostat the pressure will be lower in the engine than with it - even with the same pressure rated radiator cap. Higher pressure helps prevent localised hot spots (boiling @ the surface of the water jacket around the exhaust port for example) from forming, which reduces the chances of overheating and detonation.

I'm going to quote some text from four-stroke performance tuning by A. Graham Bell (which I've done a few times before on this forum )
By pressuring the system using a 14psi radiator cap the boiling point is raised to approximately 125C at sea level. As well as preventing boiling when the engine is switched off, the radiator pressure cap also serves to stop gas bubbles in a number of other situations. For example, a road engine may be given a lot of throttle at low engine speed, which will give rise to rapid heating of the combustion chamber, exhaust port and valve area. At low engine rpm the water pump is turning slowly so the water flow is limited and the water pump will not be creating any pressure in the block and head. It is only the radiator cap that stops this sort of localised boiling.

A similar sort of thing occurs when a race car pits. The top of the engine is extremely hot because of all the full-throttle driving out on the circuit, but now, with the engine idling while adjustments are carried out, tyres changed, etc, the engine would boil without a pressure radiator cap.

However, when water pump speed increases to the peak efficiency speed of 4000-6000rpm it is not the radiator cap that stops boiling but water pressure created by the water pump. Even many race engine tuners do not seem to understand that regardless of the radiator cap pressure a water pump spinning at maximum efficiency rpm will produce a pressure head of around 30-40psi in the engine block and head when water flow out of the head is limited by a thermostat or restrictor plate. This pressure packs coolant around the top of the cylinders and around the combustion chambers to carry away combustion heat and stop an insulating blanket of gas bubbles forming in these areas.
So please, agent_d, stop telling people coolant moving too fast will overheat engines - it won't, it's just wasting energy.
Old 07-23-05, 02:52 PM
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Originally Posted by pengarufoo
as far as I know moving coolant 'too quickly' through a motor will not cause overheating, it will simply be inefficient. And I mean as a result of too high a pump speed, you're just wasting energy turning it faster (pumping water faster) than necessary.
No. What happens is without one the heat of the engine heats up all of the water, basically to a localized point. This point eventually reaches a high enough number where the coolant no longer has room for expanding temps thus a temp to high to cool below 200F. This means from here on out your engine will be gradually overheating; this happens b/c the coolant is flowing through the RAD to quickly. The TS will retain coolant inside the RAD when not needed. This retention allows the coolant to be cooled down by the ambient air. The longer it is in there the colder it will become. When the TS senses the engine temp is to high it starts to open up, allowing new freshly cooled coolant to flow into the motor and bring the temps back down.
Originally Posted by pengarufoo
As for the thermostat, you want to run a thermostat because it provides a necessary restriction in the coolant system. This is not to slow down the flow, it is to increase the coolant pressure behind the thermostat caused by the pump. Without a thermostat the pressure will be lower in the engine than with it - even with the same pressure rated radiator cap. Higher pressure helps prevent localised hot spots (boiling @ the surface of the water jacket around the exhaust port for example) from forming, which reduces the chances of overheating and detonation.
I am calling bs

Last edited by iceblue; 07-23-05 at 02:55 PM.
Old 07-23-05, 03:11 PM
  #41  
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take the radiator to a radiator shop and have it flow tested, it may be partially blocked. also check the system for leaks with a cooling system pressure tester.


i have run no t-stat in my rebuild for 8k miles with no issues even on 108* F days with the A/C on so there is many BS statements on this thread. it may not be as efficient but it is still efficient enough..

and there is NO such thing as a lifetime coolant, every cooling system develops deposits and corrosion/sediments after a while and is why the coolant needs to be changed much like engine oil.

Last edited by RotaryEvolution; 07-23-05 at 03:15 PM.
Old 07-23-05, 03:26 PM
  #42  
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lol pengarufoo, you didnt read anything i posted, read it again, i didnt say it would overheat, i said the hot spots would get hotter, it flows TOO FAST FOR THE COOLANT TO ABSORB ANY HEAT FROM THE ENGINE BLOCK, thus the hot spots in the engine do NOT GET ANY HEAT SOAKED OUT OF IT FROM THE COOLANT, and it makes the hot spot hotter, i never ever said it would overheat the engine, it just makes the car very inefficient, you lose power, and gas mileage, etc etc etc.

thats fine Karack, dont run with a TS, its not my loss; as for lifetime coolant, read on evans' site.

when everyone figures out how a cooling system is actually supposed to work, they'll see, coolant temp means **** if your engine cant get rid of the heat its generating, and without a thermostat the coolant flow is too fast to absorb any of that heat that is being generated, it just keeps the coolant from heating up so your heat gauge shows its at a low or normal temp. its not going to overheat, the hot spots are just not gonna get the heat soaked into the coolant, and its gonna make the engine very inefficient.

as for that quote, ok, the coolant system has a routing through the block, or housings of any car, at the combustion point what is happening, its exploding the fuel and generating a very large amount of heat, the area around the coolant passages is where it gets hottest (thats why its designed for the coolant to flow through there), when the coolant is just blowing by that area, whats happening?? it is not absorbing any of that created heat from that area of the metal, its the hottest part of the engine through the coolant system, thats why its called a hotspot, and when none of that heat is absored, what happens then?? it gets hotter, and it makes the engine work inefficiently, both losing power, losing gas mileage as well as other cons, when the coolant has a chance to sit in that area for a short time, the heat is transferred to the water, its then carried to the radiator to cool that part of the coolant down again to be recirculated back to that hot spot, when its not absorbing any heat there is nothing that needs to be cooled, so the coolant temp sensor will say your temp is fine.

if you cant understand that, then you need to go back to high school, if you wanna spread that information fine, people stupid enough to follow it will suffer.

do what you like, im finished here.

Last edited by Agent_D; 07-23-05 at 03:42 PM.
Old 07-23-05, 03:48 PM
  #43  
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agent d lives in freaking hot *** new mexico i think he knows cooling systems....... the intelligence level of the forum is starting to scare me.. next person who starts arguing over some dumb **** im bringing a gun into the forum high school and popping all of ya!
Old 07-23-05, 04:37 PM
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heh

more text from aforementioned book:

An old wives' tale states that if you discard the thermostat or the restrictor the engine is damaged because the water is flowing through it too quickly to draw off excess heat, or it is flowing through the radiator too fast to give up its heat. This is not so; what causes the engine damage is insufficient water pressure to pack the coolant in tight around hot spots in the engine. Then any water that hits these hot spots dances about like water droplets on a sizzling barbecue plate without drawing off any heat. As the water boils off, the size of the hot spot grows as a bigger and bigger steam pocket forms.

In reality we want a reasonably rapid water flow through an engine, as this tends to reduce the incidence of stagnant high-temperature pools. Additionally the rapid flow will scrub off gas bubbles as they appear in the hottest parts of the engine before they have a chance to congregate into an impenetrable steam pocket. In fact, the solution to cooling problems is not so much a matter of moving more water through an engine, as moving less more rapidly. This will pay large dividends in more hp and better engine reliability.
you guys can call BS all you want, at least I'm quoting a reliable source (ISBN 1 85960 435 8) you just pull BS out your ***.
Old 07-23-05, 05:27 PM
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more on the subject:
http://yarchive.net/car/radiator_diagnosis.html

JGD's posts have ALWAYS been very informative and pretty damn consistently spot on.

from the above URL:

From: jgd (John De Armond)
X-Source: The Hotrod Mailing list
Date: Feb 1992
Subject: Radiator testing

>How about too high of a flow-rate John? Where the coolant does not
>remain in the radiator long enough to get rid of it's heat? I think
>this is what I'm experiencing with my overheating problem.

<stamp> <stamp> <stamp> <stamp>

There! That rumor is finally dead! I know the hotrod magazines like to
parrot it but it just ain't true. Think of it in terms of fluid dynamics
and thermodynamics. What does higher flow get you? turbulence. What
does turbulence do? It strips away the boundary layer of stagnant water
on the surface of the radiator tube. As to not having time to get rid
of the heat, do a simple thought experiment. if the water is moving
twice as fast as before, it only has half the time as before to deposit
its heat. BUT. It will also come back around twice as often. It
all balances out. The net win is the increased turbulence.

One reason this rumor persists is that the 2 most popular purported cures
actually work sometimes. The first "cure" is to slow the water pump with
a larger pulley. The problem that is actually solved is the fact that
many stock pumps will cavitate at even moderate RPM. A cavitating pump
is very inefficient. The second "cure", restricting the outlet of the
engine, pressureizes the block a bit more so that at higher engine
speeds, the boiling point of the water is raised. That works to preventing
local boiling on stagnant areas. Steam bubbles can slow or stop
flow through small passages. The increased pressure also cuts down on
cavitation.

"Stock Car Racing" did an exhaustive article on the subject. The guy
who owns Stewart Racing pumps actually built a water pump dyno and
demonstrated all of these effects. There is also a significant
body of literature within the SAE addressing this problem.
*sigh*

And the original poster might want to read that URL, it contains quite a bit of helpful information that could solve his overheating problem - should it return.
Old 07-24-05, 02:39 AM
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Thats some NFO from clearly misinformation of how a cooling system works!
Old 07-24-05, 01:12 PM
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Originally Posted by gxlbiscuit
agent d lives in freaking hot *** new mexico i think he knows cooling systems....... the intelligence level of the forum is starting to scare me.. next person who starts arguing over some dumb **** im bringing a gun into the forum high school and popping all of ya!

His contribution to this thread is useless and full of rumors.... The worst thing is when people spread factless rumors... I have personall experience with it, and I run over 450hp....
Old 07-24-05, 01:16 PM
  #48  
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Opinion < Fact

Fact > *

Lots of people on this forum have opinions on subjects but a lot of the time it's just regurgitated information from someone else’s opinion, this is how misinformation spreads like wild fire. You should really only believe someone if they can back up their statements with information or facts.
Old 07-24-05, 01:24 PM
  #49  
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heh, i'm getting tired of these preachers who seem to think they know how the universe works and all things in it.

those of you self absorbed guys need to pull your heads out of your asses and ty listening to what some people are saying and not think that what you believe is fact!
Old 07-24-05, 02:48 PM
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well mister 450 if you take off the crush washers from your spark plugs you will get 5 more horsepower.


Quick Reply: Car overheated again. This time with no thermostat. Wtf is wrong ?



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