Temp Too Low???

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HTMLmopars

HTMLmopars

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I've been super happy with my 318 powered Valiant, never had any serious problems with the engine since the swap. I've always prided myself on how cool it runs, about 160-170 under any conditions but Seattle traffic. I've got the gauge installed to read from the top of the water pump, its a mechanical gauge that uses pressurized gas (I think) to read the temperature. I was just talking to my dad the other day, and he said that running that cold can actually be bad for the engine, causing buildup and such. My question is that is that temperature actually unhealthy, and is that location for the gauge to pull temp from accurate to the rest of the engine? Running a brand new aluminum radiator, so it seems fairly reasonable for it to be running a little cold. If it is too cold what do I do to heat up the engine (short of cardboard over the rad)? I don't know what temp thermostat is in there, but would maybe a 160 degree unit help?
 
Sounds like u have a 160 thermostat in it, that would be why ur running so cold. That's what my dart had when I got it. I put in a 180. And yes, a little more heat will keep things cleaner, burn fuel better, keep combustion camber cleaner, burn impurities out of the oil, ect.
 
I'd rather see 180 year round. You should have enough radiator to hold 180 even in Seattle.

The thermostat controls engine temp if everything else is correct. If ambient is cool enough to hold temp to 140 but the Tstat is a 180 it shouldn't open until 180.


What I'm saying is if your cooling system is correct, it should run at Tstat temp or close to it year around regardless of ambient temp.

So I'd use a 180 Tstat and if it runs 190-195 in Seattle summer heat you'll be golden.
 
180-190 is about right. Anything colder will accelerate cylinder wall wear exponentially. Hotter will also reduce emissions but decrease ping resistance.
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195 is the correct temperature thermostat for your engine.
 
I once believed that 160* was the way to go.But after allot of reading I too run the 195*.
 
AJ/FormS said:
I have run a minimum water temperature of a tic over 200 since 1999. Engine currently has over 100,000 miles and no end in sight.
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and what is the minimum you speak of ???
 
195 here as well and every day running temps vary between 190 and 210 with fans coming on at 210.
If it's cold out your heater will work better also.:D
 
68Valiant225 said:
So just to clarify, the reasing from the top of the water pump is accurate to the rest of the engine?
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Oh yea, that cleared things right up. :D

The most accurate reading of the engine temp is usually right at the top front of the intake right where it comes out of the motor.
(where the thermostat is)
 
At the pump is not right.
This is right after the water has been cooled by the rad. The temp here can be 20 or more degrees cooler than at the stat-house. The cooled water coming from the rad is then pumped into the chamber that surrounds the cylinders. The bulk of it flows to the back of the engine, picking up heat along the way.Then the warmed water flows into the heads and back to the front, picking up more heat as it comes. it also picks up some of the smaller streams coming up from between the cylinders. At the front, the two streams are stopped by the stat and merged, and diverted to the heater, or back to the waterpump,for another go-around.When the stat opens, the merged streams,now hot, move to the top of the rad. The thermostat thus sets the minimum operating temperature.
If the rad is able to cool the water to below the stat rating, then the stat will begin to close. It is trying to maintain its set-point.
If the rad cannot get rid of the heat,then you may have a problem. If you have a thermostatic fan-clutch, and a monster fan,Or a direct drive fan, this is where they take over by increasing air-flow thru the rad to shed the excess heat.Unfortunately, with a direct drive fan, you the operator still have to notice that the temp is creeping up, and increase the engine rpm to promote the air-flow, whereas the fan clutch takes care of this for you.
It boggles my mind that people will spend 4000 or 6500 or even 9500 on an engine,and try to walk the thin line of destroying it with an iffy cooling system.
Chrysler was kind enough to provide a place for us to screw in a temperature sensor,And it is in the exact right place.
 
AJ/FormS said:
At the pump is not right.
This is right after the water has been cooled by the rad. The temp here can be 20 or more degrees cooler than at the stat-house. The cooled water coming from the rad is then pumped into the chamber that surrounds the cylinders.
Chrysler was kind enough to provide a place for us to screw in a temperature sensor,And it is in the exact right place.
Click to expand...
So if my temp gauge is reading 160 here it means that I'm actually running about 180?
 
68Valiant225 said:
So if my temp gauge is reading 160 here it means that I'm actually running about 180?
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Or more, since AJ's example was an example.
I have seen gauges in the intake read 15 degrees cooler just from have a threaded adapter from the manifold to the sender.
Best is right before the thermostat as the coolant is coming up out of the motor with the sender directly in the flow of the coolant.
 
I dont have the car right now to look at as a reference, but could someone post a picture showing where the sensor should go?
 
No, it doesn't correlate directly. There are too many variables to make a blanket assumption like that.
I have never seen an SBM intake that did not have provision for a sensor within the front water crossover,somewhere near the stat-house.
 
TrailBeast said:
What intake?
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Stock 2bbl
AJ/FormS said:
No, it doesn't correlate directly. There are too many variables to make a blanket assumption like that.
I have never seen an SBM intake that did not have provision for a sensor within the front water crossover,somewhere near the stat-house.
Click to expand...
Just not able to look at it right now. When I was installing the temp gauge, the water pump just seemed like it was going to work well. Should've put more research into it.
 
If you installed a sensor into the WP, you must have drilled and tapped a hole for it, as the stock WPs have no such port.That then begs the question, is the sensor element even in the coolant flow?, or stuck in a stagnant pocket?, perhaps measuring the temp of the WP body, and not the temp of the coolant at all?

Look, I'm not trying to be a dick,to you. I'm just pointing out that the factory engineers probably thought of almost everything. When you try to out-think them, you need to have a good reason for ignoring the things they already thought of. If you supplement the factory gauge, you need to supplant it and either abandon the factory one or re-engineer,it, not the new one that you are going to trust your engine to.

Now, as an aside, I re-engineered my cooling system to take care of my engine. Automatically. I trust it to do it's job. Automatically.
I run NO aftermarket gauge. And you know how slow the factory gauge is.
As far as I care,the gauge might as well not be there,cuz I almost never look at it.
Besides, by the time I might notice an overheat, the gauge wouldn't be telling me anything that I don't already know.
If anything, the factory should have installed a missing belt sensor. I bet that wouldda saved a lot of engines. That might give you a few minutes of early warning that an overheat is pending.
For guys in hotter climes,with bigger engines,that get stuck in freeway traffic, I can see the value in a gauge.
As for me, my system takes care of that too, automatically.When the 7 blade'r kicks in,it roars; and then I am a happy camper. And the best part is it usually roars after,not-during, the run; to be ready for the next one.As long as I hear the roar, I know the belt is still on there!
 
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AJ/FormS said:
If you installed a sensor into the WP, you must have drilled and tapped a hole for it, as the stock WPs have no such port.That then begs the question, is the sensor element even in the coolant flow?, or stuck in a stagnant pocket?, perhaps measuring the temp of the WP body, and not the temp of the coolant at all?

Look, I'm not trying to be a dick,to you. I'm just pointing out that the factory engineers probably thought of almost everything. When you try to out-think them, you need to have a good reason for ignoring the things they already thought of. If you supplement the factory gauge, you need to supplant it and either abandon the factory one or re-engineer,it, not the new one that you are going to trust your engine to.

Now, as an aside, I re-engineered my cooling system to take care of my engine. Automatically. I trust it to do it's job. Automatically.
I run NO aftermarket gauge. And you know how slow the factory gauge is.
As far as I care,the gauge might as well not be there,cuz I almost never look at it.
Besides, by the time I might notice an overheat, the gauge wouldn't be telling me anything that I don't already know.
If anything, the factory should have installed a missing belt sensor. I bet that wouldda saved a lot of engines. That might give you a few minutes of early warning that an overheat is pending.
For guys in hotter climes,with bigger engines,that get stuck in freeway traffic, I can see the value in a gauge.
As for me, my system takes care of that too, automatically.When the 7 blade'r kicks in,it roars; and then I am a happy camper. And the best part is it usually roars after,not-during, the run; to be ready for the next one.As long as I hear the roar, I know the belt is still on there!
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AJ, he could have stuck the temp sender in the WP if he hast the cast iron water pump and he either isn't running a heater or he has the heater plumbed weird.
 
So frustrating trying to diagnose things over the Internet without pictures.
 
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