Feedback on Rodney Red Radiators Please

[hesutton]

normal operating temp of our engines is as high as 237 degrees.
the t-stat is rated for 195 degrees and is just fully open at 212 degrees.
diesel engines run more efficient at higher normal operating temps.these are NOT gas engines.

I completely agree, but when hauling the 5'er, I dance right at the edge of the max temp. That leaves me zero margin. Driving the truck on the verge of overheating is not fun when hundreds of miles from home with my wife and 4 year old. That's why I'm looking for ways to keep it from being an issue in the future. I'm not wanting to run the engine "cold", I'm wanting a margin of safety that I'm not getting with the stock radiator.

These trucks rarely run those temps unless they are working hard, and most of the time its not an issue. But, when a failure will strand you and your family......... it's a big deal.

Heath

 

[Black dawg]

I would love to get my engine to run too cold, It would give me room for more right foot.

 

['94IDITurbo7.3]

i have the ford t-stat and my coolant temp never goes above 190*F according to my real temp gauge.

 

[hesutton]

Alright, got the Rodney Red several weeks ago and I'm getting the intercooler installed in front of the thing. In talking with Jerry at RR, he said he puts 16 psi caps on all his radiators. My question is why? Just to increase the boiling temp? I didn't ask him at the time but I should have. Anyway, the stock system uses a 13 psi cap. What are you Rodney Red guys running? His 16 psi cap or the stock 13? Robert, I know you run a pressure less system with the Evans coolant.

Thanks again guys,

Heath

 

[Devon Harley]

yes the 16psi cap rasies the boiling point and the marine guys do the same to help prevent cavitation and ive been doing alot of research on that kind of stuff after a possable engine builder pointed that out he does all the marine core and coast guard boats here in san diego i got a spectra all aluminum and im runnin 180 to 200 pullin my horses so thats a 20 degree difference from my stock copper core

 

[Devon Harley]

im running a 18 psi cap as well

 

[dyoung14]

my 6.9 is pushing a decent amount of power i have the power to pull another 3 quarter ton 4x4 behind me on a 18 foot trailer at 60 mph up the 7% mountain thats close to me but halfway up it im burrying the temp gauge and pulling over,

with more power comes alot more heat, my pump has both screws maxed the boost is as high as it can possibly go it pegs my 20psi gauge,

if i run empty up that same mountain i can hit the bottom at 55mph and be on the governor before i get to the top running 90 mph at 250 degree water temp
im thinking my radiator my be a little stopped up but i think its more along the line of the high boost and lots of fuel, Im thinking about getting a lower tempurature thermostat just for the pure fact that when i tow and if i have to pull a mountain i can keep my water temp under control at all i have also thought of adapting a psd radiator in

 

[hesutton]

David, I've not seen lower temp thermostats for these (at least from Ford or IH). Aftermarket thermostats make me nervous. The biggest issue with using a PSD radiator is the intake and output on those are on the opposite side of the radiator compaired to the IDI. It will however, bolt right into an IDI radiator support.

Heath

 

[RLDSL]

David, I've not seen lower temp thermostats for these (at least from Ford or IH). Aftermarket thermostats make me nervous. The biggest issue with using a PSD radiator is the intake and output on those are on the opposite side of the radiator compaired to the IDI. It will however, bolt right into an IDI radiator support.

Heath

I run a 180 deg high flow in mine, same exact design as factory just doesnt have the rubber ring, all that does is make completely sure no water flows until the stat opens up and it only flows through the middle of the stat, without the rubber you get more flow as you get a gap opening around the outside as well . got it at Summit

Even without the fact that I run a zero pressure system, i kind of figure 16 is a bit high for an old diesel like these, with these freeze plugs and block heaters and other places that have habits of liking to let coolant wander past them. I figure 7 lb on something this old should be considered max anyway but if you are going to run really high temps without a mix to support it then you will need a 13 just have to do the math. Whatever you are running, it's how fast can you pull over and shut down when the poo poo hits the fan
I just feel a whole lot safer at zero with a 375 deg boiling point

 

[OLDBULL8]

One other thing that hasen't been mentioned, is the coolant mix, antifreeze and water. The less antifreeze in the mix the more efficient cooling. If you live in a climate where it didn't get cold (below 32F) then you could run straight water. I used to run straight water with a shot of soluble oil in the summer time, same oil they use at machine shops for lubrication in cutting. In retrospect, clear water absorbs more heat than a mix of antifreeze. Oh, the soluble oil lubricates the water pump, and does not leave a film of oil in the block.

Edit: A pint of sol oil in the 16 gallons is sufficient. Mix with water before adding.

 

[NO_SPRK]

im curious about the differences in cooling between a 6.9 and a 7.3

i understand the heavy curb weight, added fuel and turbos but what about the internal cooling passages?

also id love to find a electronic lockup fan clutch for these trucks. looks like the problem is that giant water pump.

if you put the radiator from a tractor the size of your hood on these engines they should stay at operating temp.. if you use a thermostat. thats its job.. minimum operating temp

also is this rodney red rad top or side tank? is the PSD side or top?

 

[hesutton]

Rodney Red and PSD radiators are top/bottom tanked. The 7.3 has plugs that decrease the coolant flow through the head compaired to the 6.9. But, new headgaskets for the 6.9 have restrictors in the same area, likely to serve the same purpose. The thinking is........ these changes were made to increase engine temps to improve emissions, but no real way to know if that was the reason or not.

Heath

 

[ocnorb]

The thinking is........ these changes were made to increase engine temps to improve emissions, but no real way to know if that was the reason or not.

Heath

I've also seen people claim that the smaller openings helped efficiency and Ford did it because they wanted the bigger 7.3L motor to have the same fuel economy as the 6.9L.

Once read a VW engineering article on their IDI where they claimed that the hotter the pre-cups could be kept without melting down, the more efficient the motor was. Isuzu experimented with ceramic cups in their IDIs- also believed to be a way to keep the heat in the cylinder and increase efficiency. I am considering ceramic coating mine when I pull the heads on it.

 

[icanfixall]

The precups have an air gap between the sides of the cup and the heads. They only touch the heads on the top and bottom surfaces.

 

[hesutton]

Gary.......... are you running a 13 psi cap or the 16 that came with the Rodney Red?

Heath