Cooling not worth a SH!T

[5.7 hemi]

I’m sure it’s not over 500, but I’ve been wrong before.

My dads 505 cools just fine in his Challenger RT that I built. His car is also a factory ac car, so I’m at a loss as to what’s going on with mine.

 

[not so famous bob]

I’m sure it’s not over 500, but I’ve been wrong before.

My dads 505 cools just fine in his Challenger RT that I built. His car is also a factory ac car, so I’m at a loss as to what’s going on with mine.

YOU COULD PULL THE THERMOSTATE AND CHECK IT. also COULD TRY NO THERMOSTAT AND RUN A PLATE W/ DIFF SIZE HOLES IN IT . I used to run a plate w/ a 5/8 hole in it on my 600 horse sbc.---------DAM, I cant keep my figure off the cap button !

 

[5.7 hemi]

Milodon 180 high flow thermostat works, was tested before I installed it.

It’s low speed air flow that’s the problem. So I’m gonna mess around with some dual Derale fans that I have as they do 3750 cfm. The shroud is too thick, so some cutting will be in my immediate future.

 

[Ski 61701]

What ive done in the past to see if the fan clutch was locked up while running is to take a decent size towel thats bunched up and start to apply pressure to fan blade. If the cluch mech is working that towel wont stop it, and you can tell. If the clutch is bad the applied pressure from the towel will stop the fan blade and thus all the clutch is doing is just freewheeling.
Just have to be careful if you try this method, watch your fingers and loose clothing. Aka do it at your own risk.
Have you tried a solid blade fan to see if that drops youe temps?
Are your pulleys properly matched eg: crank and waterpump? Might be you are over spinning water pump aka cavitate. Or not spinning it fast enough. I believe there is a proper ratio between the pulleys that might need to be looked at.
How about your timing is it retarded and might need to be advanced a tad?

 

[Ironbuilt]

Hey 5.7, try this. It solved my heat problems.

https://www.flowkoolerwaterpumps.co...ig Block MOPAR<br>(1958-78)/product_info.html

 

[5.7 hemi]

I’ll try a rolled up magazine, I’ve alread lost 1 eye, don’t want to lose anything else.

Fixed fan didn’t pull enough air as the blades aren’t as “deep pitched” as a clutch fan.

I do have a new Flowkooler pump in it now.

 

[65RoadRacer]

Also, If you're going with a high flow pump and flow is great, you might be flowing too fast for the radiator to dissipate heat. For 500HP, a two row 1" or a three row (5/8") would be enough. You have coolant flow, but not enough air flow, so slowing the coolant down might help, as well as getting your fan problem handled. If a box fan didn't help, maybe a conventional pump to slow it down.

 

[5.7 hemi]

I’ve had a conventional pump on it, still the same problem.

The pulleys are matched from CVF, I have the “Beast” ac, power steering setup.

 

[65RoadRacer]

Yeah, that's a good kit, I like CVF Racing.. Nate's a trip!

You have answered everything that was suggested, and my only advice at this point is that you need to fix your air flow issue first. If the clutch fan isn't locking up and providing about 2700-3300 CFM, then you won't get it cooled. I was at about 2200 CFM and got up to 200, added better fans (electric) and it's now over 2800 CFM and idles at about 180-185.

On a side note, what coolant are you running? Please say the green stuff and not the red/orange crap.

 

[5.7 hemi]

Lol! Green with distilled water approximately 70/30. It rarely gets below freezing here just south of Fresno.

I agree, it’s air flow, as in not enough. This Derale dual fan set up does 3750cfm at full boogie, I’ll somehow get them on there and working, just won’t be Roadkill style! Lol!!

 

[65RoadRacer]

Mix 50/50 with distilled water will be fine. You don't need 70% coolant, they don't really recommend that. I use Prestone exclusively. I get customers asking me why I recommend it, and it's simple: I've used it in every car I've owned for the past 40 years and never had a problem with cooling other than failed pumps or clogged radiators. The Derale is a great setup, I'm not a fan of the PWM, though. I had one, and removed it because I'd go out in the garage and the fan motors were whining... just warm enough to trigger the PWM, but not enough to spin the fans.

 

[5.7 hemi]

I’m doing 70% distilled water, 30% antifreeze. Water is better at cooling, the antifreeze is there just tool help with the occasional low temps and water pump seal.

How did the fans whine? You got me curious on that.

 

[65RoadRacer]

Still, 50/50 is recommended by Prestone. I've been working with them and there's no real benefit to using a different ratio. Plus, the more water the lower the boiling point.

They recommend connecting the PWM directly to the battery, and it's based on current. When the temperature starts to rise, the PWM (Pulse Width Modulator) keeps the full current from spiking the fan motor by allowing current gradually. At lower temps, the fans spin slower because the current (voltage) is limited. When it gets warmer, the current flow is increases, thus increasing the voltage, and the fans spin faster.

At very low temps, the current is very minimal and not enough to spin the fans. Usually, your coolant is going to get warm quicker so it's not as noticeable, but it was getting rather warm in my garage and the temp sender wasn't reading enough to spin the fans at full speed, so I had the adjuster turned all the way down.

The whining is because the fans are trying to draw current, but there wasn't enough from the PWM, so the noise was the current struggling to spin the fans. It's a nice unit, but didn't work out well for me.

 

[5.7 hemi]

I gotcha. Thanks, now I have s better understanding of how it works.

I’ll switch to 50/50, no problem there.

 

[dart4forte]

Did you burp the system?

 

[5.7 hemi]

Yes, all the bases have been covered.

 

[rlem1977]

I gotcha. Thanks, now I have s better understanding of how it works.

I’ll switch to 50/50, no problem there.

Investigate Evans Waterless. Might help.

 

[5.7 hemi]

That just raises boiling temp, that’s all.

 

[rlem1977]

That just raises boiling temp, that’s all.

Yes, which reduces steam production which reduces pressure which reduces heat. If you're considering a 50/50 mix of standard coolant then you are doing the same thing. It's a suggestion, good luck.

 

[Ski 61701]

I’ll try a rolled up magazine, I’ve alread lost 1 eye, don’t want to lose anything else.

Fixed fan didn’t pull enough air as the blades aren’t as “deep pitched” as a clutch fan.

I do have a new Flowkooler pump in it now.

If you do use a small towel, just be ready to let go of it in case the blade grabs it. You'll know it as soon as you start to apply pressure to blades.
Have you contacted Hayden to see what they have to say? I remember as a kid selling autoparts the fan clutch boxes had arrows on the saying something like this side up. I remember asking an old timer why they marked like that. Answer was something to the fact if the box was stacked wrong the clutches inside the unit would get messed up because they weren't covered in the fluid. I don't remember if box was stacked wrong how long it would take to mess things up. But the old timers were adament about proper stacking of the fan clutch boxes as they sat on the shelf. Thinking about it, the boxes were to be stacked as if the clutch unit was installed in the car.
Now this from 30 yrs ago and not sure if it still applies today. Maybe you got a couple of defective clutch units?
I understand your frustration, I went through this with an old 83 2.3 turbo coupe. It would cool fine at highway speed but got hot at an idle. Never could figure it out, other than playing with timing kinda helped. Luckily another guy was more interested in the car than me, got rid of it. That was my last Ford product.