Radiators

[MountainMoparRobin]

now that the heat is here, hittin 85-95 everyday, the 19 yr old radiator is lettin the engine temp get up to 210 degrees, this is after it went 235 degrees and blew the upper radiator hose. So I flushed the system even the heater core, new hoses, new thermostat, and still runs too hot. I got up off money and ordered the new Aluminum Cross Flow with trans cooler attached, over $300.00, why ? because I need to be able to run 100 mph and have the engine stay cool, and from last years Cruise fosh69, has one and while my copper/brass was at 190 degrees his was at 160 degrees and you could put your hand on his and not even get hot! my radiator should be in today at my house, so after workin 12+ hrs I'll come home and get started with the transformation to the Crossflow

[nfury8]

Was your old radiator a 2 or 3 row core?

[712edf]

now that the heat is here, hittin 85-95 everyday,

same here, then the sun comes up!

[MountainMoparRobin]

the current radiator was a 4 row. I got the new aluminum and it was at 6:30 pm too late to put it in, but test fitted it with the 68 and I'm shocked that it is a direct fit, and bolt holes match and the width is exact size needed. very rare that the part is this good.

[712edf]

Glad to hear its gonna "bolt-in". If I ever find my dream vehicle I could see an aluminum sizzlechecker in the works.

[big66440]

Were'd you get it from???? part #??? glad to hear everything turned out good.

[MountainMoparRobin]

Actually the reason it looked good in the 68 was their was no engine, when I set it down in front of the fan, then it became evident that the mounts on the radiator needed to be on the reverse side, so I have to make brackets to mount it in correctly should be driving it today.
I got it from Jegs part#555-51930. I'l run without a shroud also, this wil probably lead to electric fan conversion down the road.

[Rodger]

Robin

I am confused.

Why are spending that much money for a Radiator that needs
alternationed in order to fit ??? In any posting that you have done
on this subject, you have always told others to shop at the
local pick and pull for an Radiator from any A/C equiped F-J-M
bodied MoPar.

You write of it getting hot in your area and then you say that
you are not going to use a Radiator Shrould ( when you do put
the truck together ).

At the last you say that you are now going to purchase a
electric fan. With the total picture of engery being used while
at an under 2,000 RPM engine speed, max cooling for your
area's topo summer temp's, how is the electric cooling fan
from jeg's better than a NAPA #271308 Thermo Silicone
Fan Drive at about $40 and the matching Cooling Fan ( light
duty five paddle or the HD seven paddle at less than $10
at the pick & pull ).

Most think of electric fans being used in chevy's when they
switch the engine and can not figure out how to cool it.
After looking at summer's or jeg's, the marketing/sales
department helps the person with their product.

Good Luck

Rodger & Gabby
COS

[MountainMoparRobin]

Roger,
yes the pick an pull is good, however I did not alter the radiator but instead made brackets to mount a Crossflow radiator, this would be the same that would be done with any radiator, and its new so didn't have to spend more money to get it tested. I didn't use the shroud because the old one doesn't fit the smaller but more superior radiator, which only goes to show how much better it is, for its cooling in conditions the copper/brass had problems with. its all aluminum and I accomplished what no copper/brass radiator can do, at 95 degrees outside temperature and driving @ 75mph and more for over 25 miles the temperature at the engine never got above 180 degrees. I've seen many, many, Mopars with electric fans one of which live by you and you associate with him alot, etsweptster, without the fan I will open up room for even more horsepower on the 440
The surperior cooling was discovered last September at the Cruise both you and I attended, fosh69 has the aluminum radiator also and upon seeing and feeling all the copper/brass radiators being hot in excess of 180 degrees his was so cold you could put your hand on it and it was barely warm when everyone else had radiators that were too warm for the human hand to lay on.
I just got tired of having to worry about the heat, now the transmission, gas mileage, performance, and peace of mind, all got a HUGE relief. yes it cost me, but you get what you pay for, and I would drive in the extreme heat of Texas and the south with this upgrade

[birddog_mopar]

I just ordered a Griffin 27.5" Ford style radiator Top Right Inlet, Bottom Left outlet for either my 71 D200 or 69 D100. I also got the 22" Summit Radiator shroud kit with 14" electric fan. The shroud does not match the radiator exactly but I will figure a way to make it work. The shroud is about 3/4" too tall. I knew that the 27.5" was wider than the stock radiator opening on the truck but I wanted to see if i can make it fit and I quickly tried yesterday and it doesn'r look like there will be a problem. I will take pictures and document as I go. Since I live in Fort Woth and it has already been in the 100s this week I am not going to take any chances on heat issues. Hot Rod had a good article on cooling issues a couple of months ago. Look it up on hotrod.com if you are interested.

[Rodger]

Class

The boiling point of water goes up about 3 degrees F for each
pound of pressure. With a 14 lb radiator cap the boiling point of
water in your radiator is around 250 degrees F at sea level.

Thermostat: starting to open at 160-165 and fully open at 185
degrees, but depends on where you reside and personal preference
there.

Radiator: stoke five blade fan with a silicone drive behind a fin
and tube style 3 inch core typically holding 26 quarts of mix. The
three inches makes for ALOT of cooling surface.

To be adding rows to the radiator does not eliminate overheating.
(1) the thermostat will keep the temperature to 185 (or whatever
it is) and additional rows only mean that there's more water
flowing, not that it is cooler and (2) the water pump is designed
to cause a flow of X gallons per minute so water movement
remains the same. (3) The most important things to consider
is an unobstructed radiator, clean block (& heads) good
(non-collapsing) hoses and the proper water pump. Also, if for
the fan, make sure it is operating correctly.

Many have run this system is the ugliest traffic, hills and
what ever the wqorld has to offer with the A/C full on and
have never had a problem if their sometimes maintence
is done once in a while.

Rodger & Gabby
COS

[Hewy]

Appears class is in session,Roger, what is the recommended thermostat degree for a 318 poly. I pulled a 1500 pound trailer up to 7500 feet on a hot 98 degree day with a tail wind,
The stock temp gauge went all the way over to right, well almost all the way, so pulled over shut down had a coke . After about 15 20 minutes temp dropped to just above midway, so fired drove another 1/2 hour started into steeper grade, again gauge needle all the way over. Did the cool down stop again, I looked at engine to see if any excess over flow tank bobbling or pressure swelling in hoses nothing. After arriving at destination over night checked radiator fluid level and it was OK.
The rad cap is 14 lb I don't know the thermo , but will pull it out tomorrow
Stock radiator
Stock fan
No shroud
Any instructions ?????

[712edf]

I usually toss the thermostat in the summer months, which around here can be Jan to Dec. Thermostats are fine for emissions, warming the intake quickly, a heater and reducing cylinder wear,but on my ol wore out junk COOL is the key to longetivity. I've even plumbed in a 12 gal tank into my cooling system via heater hoses (with shut-off valve) to increase coolant capacity by over 400%. Problem solved!

[MountainMoparRobin]

712edf, after living in Hawaii & then Texas I also usually pull the thermostadt in summer. However I wanted to put this new radiator to the test.
Roger I replaced all hoses, and my water pump is built for A/c and I have the fan you've been preaching about for over 19 yrs. but with everything new but the 19 yr old radiator, it was running too hot! and for the 440 since it is my daily driver, I will at times spend money on it, since it has given me such good service

[surfnuke9]

Class

The boiling point of water goes up about 3 degrees F for each
pound of pressure. With a 14 lb radiator cap the boiling point of
water in your radiator is around 250 degrees F at sea level.

The elevation you are at is not relevant here (sea level). The max pressure the cooling system will tolerate and the mix ratio of coolant/water is what will determine boiling point.

To be adding rows to the radiator does not eliminate overheating....
... additional rows only mean that there's more water
flowing, not that it is cooler and (2) the water pump is designed
to cause a flow of X gallons per minute so water movement
remains the same.

Gonna have to disagree with the above.

The ability of a colling system to provide sufficient cooling capacity for your vehicle is driven by many variables. To make a blanket statement that adding a row of cooling does not eliminate overheating is not accurate. It can and has for many many people.

Adding a row DOES result in additional cooling capacity since the total surface area of tubes/fins has increased. If you assume that the flowrate of the water pump (GPM) has not changed, but the flow area (number of tubes) has increased from 2 to 3 or 4, you will have a reduction in flow velocity in each tube.

Slowing down the coolant in the radiator allows more time for cooling and will result in a lower outlet temp from the radiator.

Many have run this system is the ugliest traffic, hills and
what ever the wqorld has to offer with the A/C full on and
have never had a problem if their sometimes maintence
is done once in a while.

Rodger & Gabby
COS

One area that alot of people overlook also are the factory installed seals/heavy rubber sheets etc that seal the radiator to the core supports.

Air, like any fluid will take the path of least resistance and that darn sure isnt through a radiator and fan assembly. If it can sneak around the radiator it will. Find all the places that air can get through your core support besides the radiator and seal them up.

You should never have to remove the thermostat to stay cool. If you do, you are simply using coolant flowrate to compensate for some other deficient material condition. restricted coolant flow in radiator, poor airflow through radiator (fan or bypasses mentioned above), poor/clogged coolant flow in heads/etc. incoprrect diameter water pump or other pully resulting in slower water pump rotation....

0ne more potential area is the water pump itself. Excessive clearances between the impeller and pump housing will result in low flowrate since some of the coolant will simply be circulating within the housing.

[Rodger]

Hola All

I like Tim's reply because it is not masking over the true problem
and telling the driver's to use this or that's marketing radiator/
electric fan's.

Here is direct from a era MoPar Factory Service Manual ( FSM ) and
the printed information in it.

It does not address the problems of the electric cooling fan when
added on an vehicle and the person does not understand the total
cooling ( or electrical ) picture since when it was printed the
electric cooling fan was not yet sold to the "know nots".

By about 1979'ish MoPar no longer used a hard mounted four
paddle cooling fan. Every Dodge Truck, Dodge Rear Drive Van
and all MoPar F-J and M cars were using the Silicone Fan Drive
with a five paddle Cooling Fan on light duty vehicle's and a
seven Paddle unit on HD versions.

Nor does it address the use of over sized ( diameter ) tyres
and what it does to the cooling ( or drive train ) system.

Again re-read what can cause the over-heating and find out
how to prevent it.

Rodger & Gabby
COS

[Hewy]

What is the factory recommended thermostat and radiator cap ? 318 poly D100 3 speed

[rjmeuer]

Royal Purple makes a product called Purple Ice and it will lower the temp 10-20 degrees, everyone who gets this stuff from us says it works great. Also you can put in a higher concentration of water, as it cools better than antifreeze.

[surfnuke9]

the purple ice and water wetter all work much better with a straight fill using Distilled water than a coolant/water mix.

[nfury8]

I am going from memory on the cap, 14-16 pounds.
Typically Chrysler recommended a 195 degree thermostat on almost
all V-8s. However, 180 is what most people will tell you to run, myself included.

Water Wetter is good stuff, it help my 440 out nicely till I got the new radiator.
Distilled water is HIGHLY recommended in all radiators! Also, when draining, pull
the plugs in the block to completely drain the water jackets. Otherwise you still
leave a couple gallons in the block when just draining at the radiator. Also pull
a heater hose to allow air to get in around the closed thermostat.