The Paradox supplemental cooling kit has arrived.
Here is the unboxing.
Tomorrow my HMMWV crossover should be here also.
So when everything is together I will assemble the kit on my 1986 M1009 6.2 NA motor.
I have added a high quality aftermarket bulb style coolant gauge but the bullb is in the only free spot on my 6.2; the water pump housing.
I will be moving it into the HMMWV crossover tomorrow when I get it installed and taking a baseline temperature reading along a route that includes highway and off-road sections up here at 9,000 feet as well as a 10% grade both down and up 6 miles.
Then I will install the Paradox by Design supplemental cooling kit seen here and repeat my test.
I will note temperatures, oil pressure (also a high quality mechanical gauge) subjective data like drivability and seat of the pants feel.
We are going to get another 10 inches of snow possibly during this time up here; winter really comes early here.
But the thing is 4 wheel drive so it's all in good fun.
Here is the Paradox by design kit I received today.
Bear in mind, it is still in development and improvements are being made to the M1009 version.
View attachment 700036
Paradox supplemental cooling Kit as shipped.
View attachment 700037
What's in the box.
View attachment 700038
The kit utilizes the coolant passage block off plates at the rear of the motor, atop each cylinder head, to return a controlled amount of water from either side to the coolant crossover and out the thermostat housing to the top of the radiator for cooling.
The intention here is to pull water from the back of the motor where in stock form it is thought; by some people, to become stagnant due to it's distance from the water pump.
The only claim Paradox makes; "You will find that our system greatly improves the circulation of coolant in the block, reduces the normal hot spots at the rear of these engines, and the failure of the rearmost cylinders typical in these blocks".
How we are supposed to "find" that is true is not stated.
I won't get into a debate on whether the claims of "hot spots" or "failure of rearmost cylinders" is true or not.
My intention with this post is to demonstrate the hot rodding and modification of my 6.2 CUCV M1009.
If I find anything along the way, all the better.
If I have spent money for nothing, so be it.
View attachment 700039
This jumper wire is intended for the engine block temperature lockout switch to disable the glow plugs when the water jacket temp is over 125 degrees.
Apparently on the 6.2 in the HMMWV this switch is located in the passenger side block off plate.
On my M1009 this plate is blank.
Therefore the jumper is not needed as my temp switch is located in the engine block above the starter.
However, I will toss the jumper in the glove box for the day that switch dies and my glow plugs quit working, if it comes to that.
However in the Driverside block off plate sits the glow plug thermister which tells my glow plug card what temp the engine is at so it can compute how much glow time and after glow is neccesary.
If you are running a manual switch you can ignore this sensor.
Those with a glow plug card in operation must relocate this sensor at the present time.
Thus the HMMWV crossover tube swapped onto the M1009 6.2.
It has many more threaded taps than the stock M1009 crossover and I am hoping to relocate the return for this kit, my bulb for the after market temperature gauge, and the glow plug thermister to the HMWWV crossover.
View attachment 700040
The Paradox by Design kit came with full color instructions and that are very concise and easy to read.
Why this kit?
#1 reason for me; The 10% grade to and from town.
It is not just any 10% grade.. it is Highway 14A on the west side of the Bighorn Mountains of Wyoming.
It eats cars and trucks new and old.
It is a killer.
Sure, right now we are heading into winter.
But I got 3 years left on my contract and I have to drive from 9,000 feet down to Lovell which sits at 4,500 feet and back to shop for the lodge and occasionally tow a garbage trailer.
It can range from 105 degrees at the bottom of the mountain to 75 at the top on the warmest summer day and from -20 at the bottom to -40 at the top on the coldest winter day.
While I just installed a New 4 core all brass and copper radiator and Delco water pump, I also wanted to do everything I can to optimize the cooling system.
Also installed a Gates 33924 190 thermostat and a Stant 10331 16lb radiator cap.
Balancing the temperature of the cooling system from the front to the rear of the block seems like a good idea.
It will take me a few days to get the data depending on weather and the UPS man delivering that crossover tomorrow.
I am not expecting miracles.
In fact I don't expect anything.
In the literature included with this kit by Paradox they state clearly "Overall system coolant temperature will not change significantly as that is a function of thermostat regulation".
The idea of this kit is to balance the temperature of the coolant across the cylinder block and reduce hot spots; particularly the rear most area furthest from the water pump. (my understanding, not their words).
There is anecdotal evidence to suggest that this will improve performance and reduce felt cabin temperatures.
They are not claiming anything specific.
We will see what we see.
Here is the unboxing.
Tomorrow my HMMWV crossover should be here also.
So when everything is together I will assemble the kit on my 1986 M1009 6.2 NA motor.
I have added a high quality aftermarket bulb style coolant gauge but the bullb is in the only free spot on my 6.2; the water pump housing.
I will be moving it into the HMMWV crossover tomorrow when I get it installed and taking a baseline temperature reading along a route that includes highway and off-road sections up here at 9,000 feet as well as a 10% grade both down and up 6 miles.
Then I will install the Paradox by Design supplemental cooling kit seen here and repeat my test.
I will note temperatures, oil pressure (also a high quality mechanical gauge) subjective data like drivability and seat of the pants feel.
We are going to get another 10 inches of snow possibly during this time up here; winter really comes early here.
But the thing is 4 wheel drive so it's all in good fun.
Here is the Paradox by design kit I received today.
Bear in mind, it is still in development and improvements are being made to the M1009 version.
View attachment 700036
Paradox supplemental cooling Kit as shipped.
View attachment 700037
What's in the box.
View attachment 700038
The kit utilizes the coolant passage block off plates at the rear of the motor, atop each cylinder head, to return a controlled amount of water from either side to the coolant crossover and out the thermostat housing to the top of the radiator for cooling.
The intention here is to pull water from the back of the motor where in stock form it is thought; by some people, to become stagnant due to it's distance from the water pump.
The only claim Paradox makes; "You will find that our system greatly improves the circulation of coolant in the block, reduces the normal hot spots at the rear of these engines, and the failure of the rearmost cylinders typical in these blocks".
How we are supposed to "find" that is true is not stated.
I won't get into a debate on whether the claims of "hot spots" or "failure of rearmost cylinders" is true or not.
My intention with this post is to demonstrate the hot rodding and modification of my 6.2 CUCV M1009.
If I find anything along the way, all the better.
If I have spent money for nothing, so be it.
View attachment 700039
This jumper wire is intended for the engine block temperature lockout switch to disable the glow plugs when the water jacket temp is over 125 degrees.
Apparently on the 6.2 in the HMMWV this switch is located in the passenger side block off plate.
On my M1009 this plate is blank.
Therefore the jumper is not needed as my temp switch is located in the engine block above the starter.
However, I will toss the jumper in the glove box for the day that switch dies and my glow plugs quit working, if it comes to that.
However in the Driverside block off plate sits the glow plug thermister which tells my glow plug card what temp the engine is at so it can compute how much glow time and after glow is neccesary.
If you are running a manual switch you can ignore this sensor.
Those with a glow plug card in operation must relocate this sensor at the present time.
Thus the HMMWV crossover tube swapped onto the M1009 6.2.
It has many more threaded taps than the stock M1009 crossover and I am hoping to relocate the return for this kit, my bulb for the after market temperature gauge, and the glow plug thermister to the HMWWV crossover.
View attachment 700040
The Paradox by Design kit came with full color instructions and that are very concise and easy to read.
Why this kit?
#1 reason for me; The 10% grade to and from town.
It is not just any 10% grade.. it is Highway 14A on the west side of the Bighorn Mountains of Wyoming.
It eats cars and trucks new and old.
It is a killer.
Sure, right now we are heading into winter.
But I got 3 years left on my contract and I have to drive from 9,000 feet down to Lovell which sits at 4,500 feet and back to shop for the lodge and occasionally tow a garbage trailer.
It can range from 105 degrees at the bottom of the mountain to 75 at the top on the warmest summer day and from -20 at the bottom to -40 at the top on the coldest winter day.
While I just installed a New 4 core all brass and copper radiator and Delco water pump, I also wanted to do everything I can to optimize the cooling system.
Also installed a Gates 33924 190 thermostat and a Stant 10331 16lb radiator cap.
Balancing the temperature of the cooling system from the front to the rear of the block seems like a good idea.
It will take me a few days to get the data depending on weather and the UPS man delivering that crossover tomorrow.
I am not expecting miracles.
In fact I don't expect anything.
In the literature included with this kit by Paradox they state clearly "Overall system coolant temperature will not change significantly as that is a function of thermostat regulation".
The idea of this kit is to balance the temperature of the coolant across the cylinder block and reduce hot spots; particularly the rear most area furthest from the water pump. (my understanding, not their words).
There is anecdotal evidence to suggest that this will improve performance and reduce felt cabin temperatures.
They are not claiming anything specific.
We will see what we see.
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Most of Florida is as flat as a pancake. I live about 90 feet above sea level. I can't imagine being as high up as you are!!! Someday I will visit Bighorn. I'd love to see what three dimensional terrain looks like! 
