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cooling overkill??

3K views 17 replies 9 participants last post by  RoadsterTuner 
#1 ·
well, first off my cooling system consists of 949 coolant re route, no heater core, eliminated mixing manifold, flyin miata aluminum radiator, two bottles of redline water wetter, distilled water, stant 180 degree t_stat and one piece flyin miata lower radiator hose. ok now the "problem". i installed my t_stat last night and gurgled the system of air, topped off everything and drove round. no problem. got up this morning walked out side started my car let it warm up and set off for daycare. never got over 60 mph the whole trip. temp looked good. right where it should be. started to work after a stop at daycare and found myself almost alone so i stretched my legs. temprature quickly dropped down to cold?!? slowed down and it slowly climbed back up to normal. not knowing what just happened i pick the speed back up and same thing happened. when i stopped at work i touched the top of the rad. hot. bottom very cold. couldn't have anything to do with the fans as they are unplugged so.... yea. it was in the 50s this morning too. is this something i need to worry about or have i just went overkill with my cooling system??

thanks for any information and im very sorry about all the spelling of puncuation mistakes.
 
#3 · (Edited)
Very good.
Over cooling is not unheard of.
On some snow only rally machines they have shields built in certain areas to help keep things WARMER =]
My car will over cool on the Baldy downhill from GMR.
I will be off throttle and in high Vac for over 5 min. Temps are usually low and sometimes under 32*
Yep.
My advise is use a stock T stat with no mods to it.
Maybe even a 195* or 200* one.
No problems with removal of the heater hoses?.. Is That good?..
PICS?..
 
#4 ·
LoL ....that is all. If you have no idea how the cooling system works, you shouldn't be f*king with it. Clearly replier #1 who knows everything aboout coolant flow :)woolery:) missed the major f*k up. Replier #2 almost caught it.
 
#5 ·
Helpful answer without smacktalk:

When you eliminated your mixing manifold, you eliminated a way for your coolant to circulate when the thermostat is closed. This creates an oscillation effect in temps because coolant isn't circulating at all when your thermostat is closed. The rapid hot/cold fluctuations aren't very good for your engine either.

This setup is also bad for your water pump, as it'll keep trying to pump coolant with nowhere for it to go.

I'd suggest that you put the mixing manifold back in place, close the heater core loop, and put a restrictor in the return line (simulating the back pressure caused by the heater core). This will allow coolant circulation when the thermostat is closed and will prevent temperature oscillations. It'll also save your water pump and reduce risk to your engine block from the temp oscillations.
 
#7 ·
Helpful answer without smacktalk:

When you eliminated your mixing manifold, you eliminated a way for your coolant to circulate when the thermostat is closed. This creates an oscillation effect in temps because coolant isn't circulating at all when your thermostat is closed. The rapid hot/cold fluctuations aren't very good for your engine either.

This setup is also bad for your water pump, as it'll keep trying to pump coolant with nowhere for it to go.

I'd suggest that you put the mixing manifold back in place, close the heater core loop, and put a restrictor in the return line (simulating the back pressure caused by the heater core). This will allow coolant circulation when the thermostat is closed and will prevent temperature oscillations. It'll also save your water pump and reduce risk to your engine block from the temp oscillations.
im asking you personally cause you seem to give nice answers with out calling me an idiot. i drilled two extra 16th holes in the t stat and when i put it in i did it so the pressure would push it open. am i doing this wrong?? i thought doing that would help keep the pressure from building up and causing leaks. the temp stays normal till i get in the upper rpms and stay there.
 
#6 ·
i already installed a factory t stat. and i have had not one single problem at all with the heater core delete. i thought i was doing everything correctly. taking hot water from the block and puttting it right back in to go right back through again with out being cooled just seemed like i was going against what i was trying to do to begin with which was remove heat from the cooling system.
 
#8 ·
mr.woolery clearly knows what hes talking about so i would just try what he suggest and "put the mixing manifold back in place, close the heater core loop, and put a restrictor in the return line (simulating the back pressure caused by the heater core)."

if it still over cools then all i can say is goodluck :)
 
#11 ·
Why would you remove the t-stat in the cold months? That will make it worse: it will take the motor even longer to get to normal operation temperatures...if it can even make it there.

The best advice here is to do what Woolery suggests: Bring the heater core outlet back into the water pump inlet. This will allow the motor to circulate coolant when the thermostat is closed and get the motor up to temps quicker. Right now, the only way you can circulate coolant is through the radiator...so the coolant is always cold coming into the motor. All you really need in a good setup is a thermostat to operate, when the temps get too hot, it opens up and regulates the temps, the large radiator you have supplies cold water and the thermostat stabilizes. It's typically only when you come to a stop that the fans will ever need to kick on. But without the hot water being able to circulate through the motor when the thermostat is closed, it overcools the motor. Waste of gas, and it's probably running outside the tolerances for the piston rings and even too cool of oil temps.
 
#15 ·
Why would you remove the t-stat in the cold months? That will make it worse: it will take the motor even longer to get to normal operation temperatures...if it can even make it there.

The best advice here is to do what Woolery suggests: Bring the heater core outlet back into the water pump inlet. This will allow the motor to circulate coolant when the thermostat is closed and get the motor up to temps quicker. Right now, the only way you can circulate coolant is through the radiator...so the coolant is always cold coming into the motor. All you really need in a good setup is a thermostat to operate, when the temps get too hot, it opens up and regulates the temps, the large radiator you have supplies cold water and the thermostat stabilizes. It's typically only when you come to a stop that the fans will ever need to kick on. But without the hot water being able to circulate through the motor when the thermostat is closed, it overcools the motor. Waste of gas, and it's probably running outside the tolerances for the piston rings and even too cool of oil temps.
Quoted for truth, and bolded to tell you why you get temp oscillations. ;)
 
#18 ·
Thank U David & Brain.:fab:
I thought that the mixing manifold removal was a no no.
Nice thermal pics Brain..Better than the ones on 949R.com

For the fix I would rec using -10 on the outlet manifold to connect it to the rear housing.
3/4 pipe to -10 on the outlet manifold and the fitting on the re route housing should be changed to 1/2 pipe to -10
Then You can take the measurements and have a -10 SS line made to connect the two fitting previously installed. Viola. No hose clamps - solid connections - no over cooling - And it would look great and hold up to the heat of the Mani.:woolery:
 
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