Aftermarket Radiators

[WarWagon]

The chrysler thermostat was just a single, Mr Gasket they are made for high performance and racing ,they open differently, and flow alot ,only thing is they don't block off the by pass, so at first I just restricted the by pass to 3/8 inch,I now totaly removed the by pass and put in pipe plugs, seems to work fine. You could also tap into the rear water block off plates and by pass a little off there, there is kits for that. I would like to do that and then run that through the heater core and plug the stupid quick connect up front.

You have to have some water movement to warm up the thermostat or it will stay closed while the heads boil the coolant off. This is what the bypass and heater core flow paths do. Just saying as I tried this experiment on a jet boat and failed for the no water movement when the stat was closed...

I don't think the AC clutch would be heavy duty enough. The hyd you could just make manual turn it on when you want and have a machinist put on a serp pulley.

Word is the AC compressor takes 25 HP to run. Same for the fan clutch. I have broken the belt loose on the water pump shaft with high RPM and full lockup with fan CFM test I did on my Trailblazer SS. What a jet scream from the fan and a shriek from the belt. :bigeyes: The thought of the belt coming off at 5000 RPM even with the hood closed limited the RPM range of the experiment...

So you may slip the serp belt at high RPM with a direct drive fan clutch.

 

[6.2 turbo]

My belt didn't slip with the solid stock fan, as the tensioner is very strong, the flex fan flattens at higher rpms and is very light, it is good to know about water circulating near the thermostat may be that is why the heater hose fitting is close to the thermostat , also I have drilled a small hole in alot of thermostats, the high flow ones are designed to by pass a little water. Some jeep fans have a little hydraulic motor that has a electric solenoid to turn it on. I'm going to be working on a vortec van here at home , I'll see if it has the big fan and if somebody wants a picture let me know.

 

[Anubis]

My belt didn't slip with the solid stock fan, as the tensioner is very strong, the flex fan flattens at higher rpms and is very light, it is good to know about water circulating near the thermostat may be that is why the heater hose fitting is close to the thermostat , also I have drilled a small hole in alot of thermostats, the high flow ones are designed to by pass a little water. Some jeep fans have a little hydraulic motor that has a electric solenoid to turn it on. I'm going to be working on a vortec van here at home , I'll see if it has the big fan and if somebody wants a picture let me know.

if it does .... I will want pics of it ..... and a part number if possible....

 

[6.2 turbo]

Here is a picture of a 99 GMC van 3/4 ton 350 vortec fan, it is 19 inches in diameter .Pictures of my truck.jpg Didn't see any part numbers.

 

[Michaeljp86]

Here is a picture of a 99 GMC van 3/4 ton 350 vortec fan, it is 19 inches in diameter .Pictures of my truck.jpg Didn't see any part numbers.

I looked at the one on my moms 04 yukon, its got the 5.3 and the fan is the same size but its plastic.

 

[6.2 turbo]

Ive seen the plastic ones also, not sure but some of them might have 11 blades. More blades with less pitch sound less like an airplane. Which blows more, lots of blades with less pitch or an agressive pitch with less blades? Some old GM cars only had 3 blades.

 

[Michaeljp86]

The one in my mom yukon has alot of blades, its hard to see in there.

 

[bobbiemartin]

Bobbi Martin is selling the hyd fan set up off his GEP Hummer engine IIRC

Yes I do have a hydraulic fan drive setup from a Hummer. Not sure what it would take to use on a truck, probably a lot and is for a multiple V belt setup. I also have a flex fan for a serpentine setup that would eliminate the fan clutch. See ad in classified section.

 

[Matt Bachand]

Or just pull out 1/4 of the viscous clutch in your truck now so it engages earlier. THats how I solved my plow overheat problem. NO need to switch fans, or clutches. This was done on my 2 year old OEM replacement clutch, which engaged at 215, now a tad over 200. When engaged, there is no overheating. Defanite power loss/mpg losses.

As mentioned in thread "DIY fan clutch mod"

 

[WarWagon]

Ive seen the plastic ones also, not sure but some of them might have 11 blades. More blades with less pitch sound less like an airplane. Which blows more, lots of blades with less pitch or an agressive pitch with less blades? Some old GM cars only had 3 blades.

Blades, pitch, diameter, this is boat propeller stuff. Add to this that you have a limited amount of torque that the fan clutch will provide as Kennedy Diesel compares the 20" and 21" In short the bigger fan could slip the clutch more robbing HP and generating heat in the clutch. Not sure I agree with that as you would think more slipping would transfer more TQ. But viscus drives are goofy anyway...

Or just pull out 1/4 of the viscous clutch in your truck now so it engages earlier. THats how I solved my plow overheat problem. NO need to switch fans, or clutches. This was done on my 2 year old OEM replacement clutch, which engaged at 215, now a tad over 200. When engaged, there is no overheating. Defanite power loss/mpg losses.

As mentioned in thread "DIY fan clutch mod"

Yes good mod idea. Fan clutches do age and after 5 years are "junk" due to loosing 2-300 RPM per year. The gunk build up on the front of our factory clutches is the working fluid aka the clutch is beading to death and quits locking up at a usable speed/torque transfer. The fluid needs to be inside the clutch to do any good... ):h If bending the spring gets more life out of them - but mine failed that test as it is 'empty' of the fluid.

 

[Brooklyn Tow]

Or if you want a clutch that NEVER disengages......Buy a Kennedy, for twice the price of everyone elses severe duty clutch....):h