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I have a wizard cooling aluminum radiator dual core radiator
It is not a cross flow but it is supposed to be good.

I have big block and of course I should go to a cross flow etc, but that is more money, I am hoping to put that off if I can.

Now for the question.

When driving down the road the temp stays around 180, however when I am at a stoplight or in traffic it jumps up to 220 pretty fast.

Next I have a standard mechanical fan.

1st. Since I have an automatic trans that is cooled by the radiator, If I ad a cooler separate from the radiator, will that cause the radiator to cool the engine better since it does not have hot trans fluid flowing thru it.

2nd, I am thinking of going to electric fans since I already have them, would that be enough to make a difference/

I know you can only guess but it helps.

Thanks

Otis

 

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Otis you`ve pretty much answered your own post, doing what you suggested will reduce the temp in the radiator, you could try a shroud around the fan first, or increase the fan blades, thermos will defintely cool the radiator down?
 

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Hi Otis, I have a couple of questions. Do you have a shroud around the fan and if so is it spaced properly? That will make a HUGE difference.I personally would rather have the electric fan with a good controller. As far as the trans cooler I worked with a guy years ago that used to work for Trans specialties. He told me they did a bunch of testing and found that they could keep trans temps cooler by using a large remote cooled and NOT going through the radiator. I don't know if the trans fluid would have the same effect on the coolant or not. We have been using seperate coolers for years with no problems.

Good Luck.
JB.
 

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Stuff that cools

Very hot transmission fluid definitely adds heat to your engine coolant in the radiator and just before going back into the engine. Removing the transmission lines from the radiator and installing a separate transmission cooler away from radiator air flow, such as under the front filler panel, will be much better for engine and transmission cooling.

Using a 17” 6 blade fan with fan shroud will pull much more air through the radiator in slow traffic at stop and idle to increase cooling then.

High volume water pumps and even stuff like radiator hoses with smooth inside walls as opposed to ribbed ones help with coolant flow.
 

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A shroud and properly spaced fan should cool that sufficiently Otis !

Just as a side note....
I was told by a local transmission repair outfit a few months back Not to put on a separate cooler for the trans unless I was going to be doing a lot of trailer towing or driving in a very hilly area and loading the trans up a lot...
when I asked why he told me that the trans fluid did not actually increase the temp in the radiator a great deal and it was in fact a help to keep the trans temp at a constant level as they can run too cold and that can have a detrimental affect !
Now I am not an expert
But I would have thought a separate cooler could only help all round
but what I was told sort of sounded logical too
Any expert advice out there ? :confused0006:
 

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Lots of good advice. Key in on 50-50 mix anti freeze to water, proper timing, carb adjustment, a shroud with properly spaced fan 6 or 7 blade and no air pockets in the block. Is your motor recently rebuilt? Breaking in the motor is key to good cooling. Tight motors build more heat until they loosen up.

Don
 

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I always thought of it the way you did - that to keep the transmission oil at approximately radiator temperature was the way to go.

Some of the aftermarket builders/sellers of automatic overdrives say to run the transmission at less than radiator temperature. I always kind of shrugged this off, even thought it was wrong.

My '09 GMC pickup has a six speed auto, and an air to oil cooler. I think it's downstream of an in-radiator cooler. It also has a display for transmission oil temperature. In normal driving it rarely gets above 125 F and I've never seen it over 160 F. I haven't been doing any towing with it.

So if GM is building them this way, maybe it's not such a big deal to run it that cool, and maybe I was wrong all along, perhaps you need to.

I will say this - I do think you need a pretty big air to oil trans cooler if you run that cooler only. And it needs good airflow, if it's not in front of the radiator then it probably needs its own fan, prefererably one with a thermal switch to activate it.
 

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Lots of good advice. Key in on 50-50 mix anti freeze to water, proper timing, carb adjustment, a shroud with properly spaced fan 6 or 7 blade and no air pockets in the block. Is your motor recently rebuilt? Breaking in the motor is key to good cooling. Tight motors build more heat until they loosen up.

Don
 

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"Tight motors build more heat until they loosen up."

These days engines aren't built "tight". Bearings and rings don't wear significantly initially or any other time, nor do they require "break in". They run what they run from the get go.

I guess you can still buy cast iron rings that do need to be seated, and will have significant friction while doing so. But they have a lot of friction afterward too unless they are worn out, which happens quickly. Few use them any more. I think that you need enough margin in your cooling system to handle that or your'e going to be in trouble anyway at some point.
 

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My car does not have a big block (has a 283 powerpack) but here's how I'm cooling it. I bought a 16 inch ball bearing fan (guaranteed for life) from Skip White and mounted it directly on the front of the radiator. Has it's own shroud. I am running it as a pusher. I removed the stock fan blade .
Being a HVAC contractor I Installed a Honeywell circulator pump thermostat. (mounted the sensor at the front right side of the radiator between the radiator and the radiator support) I am using a RIB (relay in box) relay to control the fan. They work perfectly because the coil voltage is from 10 volts up dc or ac. They also have a led lamp indicating contacts made. I ran a 25 amp fused line from the battery to the relay in contact and the other contact goes to the fan. I ran a fused wire from my red circuit at the fuse block to the relay coil. The fan can run when the ignition is off like new cars do. I have the thermostat set about 175 with a 10 degree differential. So far so good cycles on and off even at idle. My car isn't drivable yet. Only observing stationary so I won't know how it will do until it's on the road. Bought car Oct. 09 14 months and counting . Car has not been on the road other than driving 2.5 miles to my house for over 20 years. Jim
 

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"Tight motors build more heat until they loosen up."

These days engines aren't built "tight". Bearings and rings don't wear significantly initially or any other time, nor do they require "break in". They run what they run from the get go.

I guess you can still buy cast iron rings that do need to be seated, and will have significant friction while doing so. But they have a lot of friction afterward too unless they are worn out, which happens quickly. Few use them any more. I think that you need enough margin in your cooling system to handle that or your'e going to be in trouble anyway at some point.
I can only speak from my own experience and information gained from a local renouned race car engine builder here in NY who built my motor. When I had my 283 and 350 engines built (by two different shops) Both motors ran a tad on the hot side. I brought both back to the shops (installed in my cars) and had both engine builders tell me that they needed to be broken in (around 1K miles) before the temps would normalize. Both said there was a lot of drag on the rings until they are seated. Following their advice I drove both cars around 1K miles and now both temps run consistently in the normal range of 180*.

What can I say, I don't do the machine work myself but following their advice it worked for me. Your mileage may vary :)

Don
 

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A shroud and properly spaced fan should cool that sufficiently Otis !

Just as a side note....
I was told by a local transmission repair outfit a few months back Not to put on a separate cooler for the trans unless I was going to be doing a lot of trailer towing or driving in a very hilly area and loading the trans up a lot...
when I asked why he told me that the trans fluid did not actually increase the temp in the radiator a great deal and it was in fact a help to keep the trans temp at a constant level as they can run too cold and that can have a detrimental affect !
Now I am not an expert
But I would have thought a separate cooler could only help all round
but what I was told sort of sounded logical too
Any expert advice out there ? :confused0006:
Depends on which line you plumb when you mount the cooler - mount the cooler in the flow from trans to radiator - if the oil is hotter than 190 it will remove the heat load from the oil before it gets to the radiator - if the oil is lower than 190 the radiator will warm it up for you (and that equals heat removed from the radiator - more engine cooling as well).

Plumbed in the return line from radiator to trans the oil most likely WILL be cooled excessively.
 

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I can only speak from my own experience and information gained from a local renouned race car engine builder here in NY who built my motor. When I had my 283 and 350 engines built (by two different shops) Both motors ran a tad on the hot side. I brought both back to the shops (installed in my cars) and had both engine builders tell me that they needed to be broken in (around 1K miles) before the temps would normalize. Both said there was a lot of drag on the rings until they are seated. Following their advice I drove both cars around 1K miles and now both temps run consistently in the normal range of 180*.

What can I say, I don't do the machine work myself but following their advice it worked for me. Your mileage may vary :)

Don
Differing builders will make differing statements. I personally assembled and dyno ran most of our builds for better than 6 years. ALL of our builds got a 220 degree heat tab epoxied in key places. If the solder melted out - warranty was void. Breakin should only add about 5 degrees and only during the first run in.

Racing engines are built on the loose side not the tight side. A slight heat problem is normal in a racing engine used on the street because it is running a lot slower (air, water and rpm) than it was designed to.

If the heat generated by the engine went away (with no other change such as timing jetting or cooling efficiency) - so did some of the power. Heat = power.
 

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When driving down the road the temp stays around 180, however when I am at a stoplight or in traffic it jumps up to 220 pretty fast.

Next I have a standard mechanical fan.

1st. Since I have an automatic trans that is cooled by the radiator, If I ad a cooler separate from the radiator, will that cause the radiator to cool the engine better since it does not have hot trans fluid flowing thru it.

2nd, I am thinking of going to electric fans since I already have them, would that be enough to make a difference/
Otis, what your symptoms are telling you is that you have enough cooling capacity when you get enough air through the current radiator. So the problem isn't the radiator, it's your fan.

A mechanical fan obviously runs at engine speed, so when you're stopped and idling, it's running pretty slow. It's probably not pulling enough air through the radiator at idle.

While a shroud will help, will it help enough? I don't know. If I were you, and since you have the electric fans, I would go ahead and install them instead. They turn the same speed regardless of engine RPM, so your idling cooling should be greatly improved. I don't know what electric fans you have, but hopefully you got the Spal dual 11" or something similar. Don't use a pusher fan, as they block airflow. Also, be sure your alternator is up to the job.

As for the trans cooler, I don't think it's adding enough heat to your radiator to worry about. I'd leave it as it is.
 
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