Has anyone installed a cooling system upgrade?

[deank]

I have been researching a cooling system upgrade by paradox by design. Has anyone here used it? Would you recommend it? My M1031 only has 16 k miles and I want to make it last as long as I can.
Thanks for any feedback!

Dean

 

[antennaclimber]

I have one of the kits on my M1008. Some people think it's not needed and others think it would be a good idea. My thought it's worth a try and would only be beneficial given the history of these engines with blocks and or heads failing.

I do not have any data as to it being better or worse than the stock system. The truck has been driven across the USA two and a half times without any issues.
The radiator is a aluminum and plastic unit, I have driven it thru some extreme heat conditions towing a M101A2 trailer and so far, no issues.

 

[deank]

Thanks for the reply. I appreciate the help.

 

[2INSANE]

My personal testing on running 6.2 and 6.5 motors on an engine stand shows that they all get hot in the rear of the motor. I recently installed the PBD kit on a customers motor and can confirm that the kit does balance the temperatures better on the motor. I would say this kit is now a MUST HAVE UPGRADE for any 6.2 and 6.5 motor. Here are pictures.

 

[deank]

Thank you for the input and the pictures. I am convinced I should do this now.

 

[chevymike]

I put on the PBD kit and had the stock radiator re-cored. Runs nice and cool but I haven't put many miles on it.

 

[ballencd]

I agree its a good idea but that's a pretty pricey modification. Seems you could do it with $80-100 in parts DIY style. Is that a Hummer crossover in the pictures?

 

[87cr250r]

2Insane, how did you determine your motors were running hot in the rear? Did you take measurements?

 

[2INSANE]

I agree its a good idea but that's a pretty pricey modification. Seems you could do it with $80-100 in parts DIY style. Is that a Hummer crossover in the pictures?

No it is a coolant crossover from a 93 GMC 1ton I parted out. Pictured is a hummer coolant crossover.

2Insane, how did you determine your motors were running hot in the rear? Did you take measurements?

I used a laser thermometer gun while the motors were running on an engine stand. Temperatures averaged 10-20 degrees hotter in the rear of the heads or around cylinders 7-8. That is why the piston clearance for cylinders 7-8 are meant to be wider. See pic.

Now imagine the motor up against the firewall building even more heat. The temp sensor is more toward the cooler side of the motor so if your gauge says 200 degrees, it will actually be 210-220 in the rear. Maybe more! Now imagine your pulling a big hill and your gauge says you are overheating at 220-240 degrees… Your actual temperature in the rear will be 230-260 Degrees! Now think of the history of the 6.2 and 6.5 cracking head problems over the years… Here is the reason!

Edit: No I am not getting sponsored or paid by paradoxbydesign to say these things. I am a normal bloke just like you that loves these old squares and motors!

 

[deank]

Getting closer to putting the engine back in the truck. I have installed the PBD cooling upgrade. Being that mine is an M1031 , i ran the hoses along the edge of the drivers side head and had them come out below the thermostat housing. I have ordered 2 each 90 degree elbows so I can connect to the Y-block.

 

[2INSANE]

Getting closer to putting the engine back in the truck. I have installed the PBD cooling upgrade. Being that mine is an M1031 , i ran the hoses along the edge of the drivers side head and had them come out below the thermostat housing. I have ordered 2 each 90 degree elbows so I can connect to the Y-block.

View attachment 933834

It looks like you have the 90 degree elbow on in the wrong position. It should be pointing up and the hoses run over the plenum.

check this out. Post 218

2insane’s Random 6.2/6.5 Diesel Projects

The billet wheel arrived! Look what I created! LOL! The wheel fit perfect. I had to use the old aluminum housing to get it to fit on this new made in China turbo. I can’t wait to install it for the customer and see how it does! I have never heard of anyone else building an ATS Hybrid Turbo...

ck5.com

 

[deank]

Here is the reason I cannot go over the top of the crossover. The M1031 has a governor control for the engine throttle. No room to run the hoses.

 

[deank]

Some progress today. The new 90 degree fittings came in today.

view from passenger side front

View from driver’s side front

view from below

 

[79Vette]

In my opinion based on testing with my engine, this type of cooling modification is a waste of time and money.

I can't speak for others engines or applications, but in my turbo 6.2 I have digital gauges with RTD type coolant temp sensors in the factory location in the front of the driver side head, in the glow plug thermistor port in the rear of the driver side head, in the radiator inlet hose, and the radiator outlet hose. The front and rear of the driver side head are within 10 degrees at all engine operating conditions and usually within 5 degrees. The rear sensor is almost always cooler, indicating more flow is not needed at that location.

I've swapped the gauges and sender probes around between all locations and these results are consistent. In my engine, based on testing and data there is no reason to modify the cooling flow path specified by the engine designers and built into the cylinder block.

 

[vanaisa]

GM engineers know their thing after all.

 

[911joeblow]

GM engineers oversized the cylinders in just #7 and #8 to keep the pistons from scoring the cylinder walls when they overheated and swelled beyond spec.. GM knew about the overheating at the rear and after having tried with different water pumps, dual thermostats, etc to fix it, gave up and oversized the rear cylinders. This is about as embarrassing as it can get for an engineer.

Our system is similar to what GM later did to the LS motors which they call a 'steam vent' line. It accomplishes the same thing our kits do for the 6.2/6.5 engines. This is a real issue that has added to the 'unreliable' reputation of these engines more than anything else.

In my opinion based on testing with my engine, this type of cooling modification is a waste of time and money.

I can't speak for others engines or applications, but in my turbo 6.2 I have digital gauges with RTD type coolant temp sensors in the factory location in the front of the driver side head, in the glow plug thermistor port in the rear of the driver side head, in the radiator inlet hose, and the radiator outlet hose. The front and rear of the driver side head are within 10 degrees at all engine operating conditions and usually within 5 degrees. The rear sensor is almost always cooler, indicating more flow is not needed at that location.

I've swapped the gauges and sender probes around between all locations and these results are consistent. In my engine, based on testing and data there is no reason to modify the cooling flow path specified by the engine designers and built into the cylinder block.

 

[2INSANE]

GM engineers oversized the cylinders in just #7 and #8 to keep the pistons from scoring the cylinder walls when they overheated and swelled beyond spec.. GM knew about the overheating at the rear and after having tried with different water pumps, dual thermostats, etc to fix it, gave up and oversized the rear cylinders. This is about as embarrassing as it can get for an engineer.

Our system is similar to what GM later did to the LS motors which they call a 'steam vent' line. It accomplishes the same thing our kits do for the 6.2/6.5 engines. This is a real issue that has added to the 'unreliable' reputation of these engines more than anything else.

Don’t sweat it. Everyone has a right to their own opinion regardless if the facts are wrong. Your kit works well and everyone that has it installed, has told me it works well. My personal testing proves that. The motors history of cracked heads proves the problem is there. There are several videos on line showing other customers personal tests. It’s not my opinion but a fact that the PBD coolant upgrade kit is a must have upgrade.

 

[gringeltaube]

The motors history of cracked heads proves the problem is there.

Yes, but under normal operating conditions they usually don't crack. On the other hand it takes just one serious overheat (e.g. from a failed radiator hose detected too late...) to cause one or both heads to crack between the valves. And once the heads ran dry the kit in Q. won't help at all, or....???

I think "the motors history of cracked heads proves" ...that more than often there has been abuse and negligence regarding maintenance!
These aren't bad engines. The real problem is, we don't get to know their actual "history", especially in- or out of- a surplussed MV...

 

[2INSANE]

Yes, but under normal operating conditions they usually don't crack. On the other hand it takes just one serious overheat (e.g. from a failed radiator hose detected too late...) to cause one or both heads to crack between the valves. And once the heads ran dry the kit in Q. won't help at all, or....???

I think "the motors history of cracked heads proves" ...that more than often there has been abuse and negligence regarding maintenance!
These aren't bad engines. The real problem is, we don't get to know their actual "history", especially in- or out of- a surplussed MV...

The scenario that you are talking about could happen to any motor of any make. Running heads dry of coolant would for sure crack the heads or cause serious damage of almost any motor. Lol.

The PBD kit is simple to understand. It balances the heads coolant temperatures. Without it, say your gauge is at 200 degrees, the back of the motor will be more in the tune of 210-240 degrees. With it, say your gauge is 200 degrees, the back of the motor will be 200 degrees. Make sense? So a cautious driver monitoring the gauges with the kit can have piece of mind.

 

[Valor]

Without it, say your gauge is at 200 degrees, the back of the motor will be more in the tune of 210-240 degrees. Without it, say your gauge is 200 degrees, the back of the motor will be 200 degrees.

That doesn't make sense.