Technical Cooling issues, need to pick some brains

I had thought I was making moves in the right direction but may be I have not.

When I first built the car, had a screw style water pump from 440 source with their new design cast housing, SUCKED at stop lights, would climb to 210 to 220 sitting for 8 minutes, then get going, after a few minutes it would drop down to about 190 and hover there. sometimes drop to 185.

So to counter this went and got a flow kooler water pump, Ok, I can see the thermostat cycle 3 times at the 180 to 185 range, then creep to 195 and hover there almost all the time, hmm ok, well changed to that high flow thermostat, and no change. ok...

so ditched my 14" derale fan with no shroud, put their power pack 17" with shroud, and keeps very consistent 185 to 195 except for yesterday. First time Ive ran it that hard, and then did freeway driving hoping it would drop.

Racing a bit light to light with my buddies 29 Chevy sedan, I was running this thing pretty hard (yes I won), had a snap come loose on my roof insert so pulled over to re attach, didn't want to have it start tearing something, so turned car off for 1 minute, then got back in and temp was 220-230, ok I am used to that when you turn one first off, fired it up took off, scratched my head as I entered the freeway 5 minutes later, Still rolling 210-215 degrees 10 minutes on the freeway later at 75 mph-90 mph, pulled off, did some low speed driving lowest it got down to was 205.

So we cruised back to his house, stayed 205 to 210 the whole time. So pulled up at his house, left my fan on low for about 10 minutes... got in the car to head home, temp gauge was 165...

So this has me wondering where in the blue hell have I gone wrong in this cooling system.
3 row champion alum radiator,
17" derale fan and shroud pulling 2500 cfm at high speed
flow kooler water pump that is supposed to be the "best" for cooling.
Robert shaw style, Miloden 180 degree high flow thermostat
Brand new set of Autometer gauges, temp of running around at time of gauge swap was dead on to the auto gauge ones.
Red line water wetter additive


Dodge 440 .030 over
10w30 Valvoline oil,
Nothing crazy just a good street built,
remote trans cooler,
timing is about 18 degrees at idle swinging to 36 roughly
dizzy is 6 months old and not flying around with timing, staying dead on.
.040 plug gap, and a medium heat range plug.

 

Where on the engine is the temperature probe?
Has boiled over?

 

I'm not a fan (pun unintentional) of electric fans,I have NEVER had good look cooling a car with one.

A 17" mechanical has always kept my engine cool,even sitting in bumper to bumper traffic. HRP

 

At normal driving speeds the fan should not even be needed at all, your speed should push enough air through the radiator. (Cooling systems with radiators in unconventional positions away from the wind excluded, ofcourse.)

 

Shot in the dark, when the fan is running is it blowing the air directly on the engine or out to the sides at around 45 degrees? even when driving if the fan is blowing on the engine it will have a tough time cooling. Pete

 

I agree with HRP

 

Is there anything about your car and engine combo that would make it difficult to bleed air from the cooling system?

 

Rule of thumb, running hot at highway speed - not enough radiator. Hot at low speed - not enough fan.

 

On a 440 Mopar 195 isn't "HOT" at least on any I have ever had. I wouldn't think that 205-210 was hot as my Cad 500 has a 205 thermostat in it.
Temp goes up a bit at a light or creeping in slow traffic and drops right down when the rig gets moving is normal.
In Texas this time of year it is no doubt normal if the car isn't puking coolant every time you stop.
I'm a another one who isn't found of aftermarket electric fans. They let the guys know you are one of the cool guys with an electric fan when they sit and buzz for ten minutes after you shut the car off at a rod trot but normally don't tend to move the air you need moved when you need it moved.

 

More timing, small hole in thermostat edge, fan half in and out of shroud, larger fan. smaller water pump pulley, richer idle needle settings. The size of the pulley has a dramatic effect at idle cooling.

 

Am running a 7 blade Hayden stainless steel mechanical fan on a sbc 383 stroker motor. It has done a great job for a number of years with tamps @ 190 degrees @ idle 210 stuck in traffic. I set the fan @ less than an inch from the radiator as the fan flexis from the rad @ speed. I used an old mechanix trick of putting a shop rag on the grille to see if it would hold the rag on the grille @ idle......

 

X2

 

The hopped SBC I have now, runs 180 cruising or on the freeway. Sitting in traffic, it climbs to 210 and stays there. It's never boiled over. Now, in the beginning, 210 used to get me all puckered up. I talked to the guy who built my engine and he told me he used a newer block for my build and 200-210 is fine.

I trust this guys judgement and what he said kinda made sense to me, but I've never done a total rebuild. My brothers 2009 Chevy P/U runs 220 all day long! Also, I changed my radiator fluid about 2 months ago and now, I'm seeing 195-205 sitting in traffic. I use a mechanical fan, no shroud.

 

Fred is right, 200 - 210 is no problem. However, if you still run hot at freeway speeds, you may have too thick of a radiator. Too thick, and the air cannot get through. Found this out by accident when I swapped a 3 row into a Econoline (2 row OEM). It ran hotter because the air could no longer easily get through. Might also check that the air coming through the front cannot escape through the sides, bypassing the radiator.

Cosmo

 

Temp probe is in water pump housing, right before the thermostat by 2 inches roughly.

Airflow on a model a grill shell with no hood or fenders shouldn't be a problem. And the air does go from rad dead into the motor.

Just funny how a crappy pump with no shroud got hot at lights and would calm down driving it.

Clearance issues are the main reason I went electric fan vs mechanical. I could maybe slide a 13 or 14" mechanical in there. would be tight.

And no it hasn't boiled at all, I think this weekend I will try to push it, get on freeway and go 50 miles and see what it does then. Shouldn't have to run that fan at all on freeway speeds so we will see what the air flow does. Maybe the shroud is blocking too much airflow? its deffinately good at idle I think.

And when I fill the coolant up I put it at the end of driveway at a good angle to get air out. rad hose is not higher than fill neck.

Maybe I have a lower rad hose collapsing under cruise conditions spinning 2500 to 3k on freeway?

At least I am not boiling yet. mid 90s lets see what 101 this weekend does.

What thermostats are you guys running anyways? 180-195-205?

Thanks for the help guys.

Just wanting to put more distance on my trips even in the heat. Looking to try to take it out of town a lot soon.

 

I'm running a 180 thermostat now. In the past, I ran a 160 with poor to fair results. I also noticed you're in the Spring, TX area. I'm in Houston and I feel your pain/confusion. It took a lot of trial and error to get my prior engine to cool right. Then, I blew the damn thing.

What I found was, sometimes, a cooling issue is just a matter of trial and error. Testing different things, until you get the right combo for your area and style of driving. But a few things that will get you started in the right direction are:

1. Use distilled water.
2. Use a good brand coolant.
3. Check timing.
4. Use hoses that won't collapse.
5. Make sure the thermostat and water pump are working properly.
6. Check EVERYTHING.

 

yeah driving around Houston has turned into
traffic, traffic, go fast, traffic, sit, cook, go go go, stop stop stop. finally out of town and get to sit back and ride a bit...
Yeah... its been warm lately, but better than the months of rain...
As long as you blew the motor having fun that's what matters right tfeverfred?
#6 is going to be #1 for me right now.

 

Where is the best place to put the temp sender? Head, water pump or?

 

I run straight distilled water with a water pump lube.every October I put anti freeze in.this is in my ford 390 9.5 to1 pistons, holley 4 bbl.never overheats since I rebuilt it in 2007. headers

 

Original post says "with shroud, and keeps very consistent 185 to 195 except for yesterday. First time I've ran it that hard, and then did freeway driving hoping it would drop." Seems like the problem started after he "ran it hard". All suggestions are valid for fixing cooling issues, but the cooling system didn't change. Perhaps attention should be given to the engine for anything that may have been affected by "running it hard", timing, fan belt, head gaskets, puking coolant during the hard running etc.. The coolant system didn't change

 

If you're going to use logic and reason, then we just can't talk to you....-rick.

 

If you end up concerned about the shroud effecting airflow at speed, might try flaps.

 

Follow this rule and it will solve your problem!!!

 

Where you put the temp sensor is like separating fly shit from pepper. How many degrees difference could it possibly make yet this same discussion occurs over and over again.

 

Funny that no body has mentioned synthetic oil to lower temperature in hot weather( and not all
synthetics are created equal). As Mr48chev said 205-210 in a 440 on a hot day would probably be
considered normal. The problem is that with conventional petroleum base motor oil every 10
degrees over 200 the oxidation rate of the oil doubles and the lubrication properties decrease. I
had a Harley 1200S that had a temperature problem. Harley Davidson synthetic helped a little but if
I got trapped in traffic on a 100 degree day I was in trouble. Switched to Amsoil 20 - 50W and saw
a 40 degree drop ( 220 down to 180 ).

 

The reason I asked was because when I took an infrared temp sensor around the engine I was getting a wide range of readings.

 

Whats a wide range? How many degrees difference and at what location?

 

Let's see some pictures of your fan shroud ......

 

Had a similar discussion going on at another Mopar site with a guy running a 440. In that case it turned out putting a high flow water pump on made his problem worse as well. What was happening was that the new rad hoses he was buying did not have the metal spring inside to keep them from collapsing. Every time he opened the hood to see what was wrong, it was idling or shut off and looked normal. I think the same thing may have been happening when you ran hard and then went to the freeway to cool it down... you didn't idle down enough to let the hose come back into shape. Check to see if your hose has the stainless steel wire in it for support, a lot of the new ones don't.

 

Interesting thread...
I have a 283 bored .060 over to 292 with 305 HO heads, cam and more, with a 180 degree thermostat in my '63 Biscayne, using a 1966 Impala 283 radiator.
It runs ~185 in cooler weather, and in ~90 or plus weather will run 190-195 and up to ~200 on the interstate. Idling it always cools down to ~185, no matter how hot it is outside.
I was worried about it, but the techs here quickly calmed me down to realize that this was not a problem.
I picked up a 1966 Impala 396 radiator (a bit bigger) some time back, and changed to that a few weeks ago...
Guess what.....same exact temps...
I guess being an old geezer I just didn't like those temps, but now am totally comfortable with them...
And while it ain't no big block monster, it runs like a bear
ON EDIT:
I looked into maybe a Hi flow water pump too, but quickly learned that that can make things worse, as you mentioned. The coolant needs to be in the radiator long enough to cool down, and a Hi flow pump will just push it thru too fast.