Cooling Issues

[650Hawk]

Fan was running but didn't sound like you hear other cars where it gets loud under the hood when sitting... I am so pissed..

Still sounds like a defective fan clutch to me. Just because it's "running" doesn't mean it's locked up; it will always run, but if it's not locked up it won't pull enough air. I know it's new, but I've gotten bad new ones before. Not too difficult to take it back and exchange it. Just my nickel.

 

[GreatDaneHummer]

Ok guys figured it out... After installing the CSF radiator I never would have even thought to look at how the fan shroud matches up to it. It says its an OEM replacement, drop in and go. Not so much. I will post up pictures later today to explain what my fix was but basically the spacing between the fan shroud and the radiator was close to 1/2 - 3/4 of an inch in some places letting the running fan recirculate heat inside the engine bay vs. stronger pull from the outside. I proved this idea by using high temp tape and closing up all those spacing's around the radiator and the shroud. Now you can feel the air being pulled from the front and no over heating. I would not say the CSF radiator is a bad purchase... I would simply do what I will be doing which is going to a custom shroud that is better fit for the H3.

 

[650Hawk]

Ok guys figured it out... After installing the CSF radiator I never would have even thought to look at how the fan shroud matches up to it. It says its an OEM replacement, drop in and go. Not so much. I will post up pictures later today to explain what my fix was but basically the spacing between the fan shroud and the radiator was close to 1/2 - 3/4 of an inch in some places letting the running fan recirculate heat inside the engine bay vs. stronger pull from the outside. I proved this idea by using high temp tape and closing up all those spacing's around the radiator and the shroud. Now you can feel the air being pulled from the front and no over heating. I would not say the CSF radiator is a bad purchase... I would simply do what I will be doing which is going to a custom shroud that is better fit for the H3.

Wow, now that's interesting. The CSF radiator is not cheap, I would have expected a better fit (that seems to be one of the arguments for the CSF over cheaper eBay or Amazon radiators). Pics would be great.

 

[GreatDaneHummer]

Tape fixes all lol. I am still going to add an additional E fan to the front as a pusher.

 

[amrg]

The griffin radiator made for the H3 doesnt fit with the plastic shroud either. Wil require alot of trimming to work.

 

[H3nightrod]

This seems like an easy fix.

Dont mean to hijack this thread, but I have a e-fan I was about to list. Let me know if you want to meet up and check it out.

Josh

 

[GreatDaneHummer]

You coming out to the badlands Saturday?

 

[H3nightrod]

Trying to. Still waiting for my rig to come out of trans shop.

 

[Ghostbuster]

Uhh. Odd fix. Glad it worked for you. Why haven't we heard of this super overheating issue with CSF radiators before? All because of spacing between the radiator and oem shroud? Wow.

 

[Bigunit]

Uhh. Odd fix. Glad it worked for you. Why haven't we heard of this super overheating issue with CSF radiators before? All because of spacing between the radiator and oem shroud? Wow.

There's a reason for this.
All you have to do is research where and who started "marketing" this product and you will see how the sheep blindly followed and accepted the cost of this product without disclosing its "cons". I call " b#@* s%#t!

 

[rascole]

LOL, I call bullshat on the spacing issue causing the overheating. I ran several trips to Anza-Borego over several months with my shroud still rotated up and never overheated.

 

[rascole]

There's a reason for this.
All you have to do is research where and who started "marketing" this product and you will see how the sheep blindly followed and accepted the cost of this product without disclosing its "cons". I call " b#@* s%#t!

What radiator do you run?

 

[H3nightrod]

Sounds too good to be true. I'm sure the road trip from Chicago to Attica Indiana with today heat will be the ultimate test. Only 80s but still might show some high temps.

Wish I could have made it.

 

[Bigunit]

What radiator do you run?

OEM. So far, 2 replacement OEM radiators on 4 Hummers.

 

[Woodtick]

Wow, the snake oil didn't work again? Pull my 3 out of the garage today. 93 k on the clicker,92 Ambiant temp,stuck in traffic with the Ac on max. The temp gage never went over HAlF. All original works sometimes. ????????????

 

[Woodtick]

Stop doing stupid stuff to your truck! You are the reason your truck has so many problems! I have had less problems with my 3 in 10 years,than you have in any given month. Good God,sell the 3 and just take Uber. SMFH.........

 

[alrock]

Shroud fit is important and it sounds like his fix was the fix. Weren't many variables left, including a system that might not have been pressurizing, a fan that wasn't drawing as it should or a radiator that didn't flow properly.

 

[GreatDaneHummer]

After my taping up the shroud I have not had any problems with it cooling even from Chicago to Attica and back. I don't mind issues with the Hummer, its a hobby toy also. I have learned a lot along this journey and met a lot of good people along the way. The expensive aluminum radiator wasn't supposed to be a performance upgrade, it was to fix the issues with plastic/aluminum combo radiators that like to crack. My Hummer is as much a hobby to toy with than something to drive to work. I just added a nice ARB roof rack also. Could I have just thrown it on and been done with it yes. But I had it Line X'd, replaced some plastic on the roof and put new seals on the plastic. Now I am going to add all new steel braided hoses on my cooling system with E Fan dual 13". Is it needed NO. Is it fun for me YES. If sharing my experiences with my Hummer on this forum is bothering so much then good day gentlemen.

 

[Bigunit]

Keep the posts coming. That's how we all continue to learn to keep our rigs running.

 

[JPaul]

don't let it get to you, some people are just grouchy, and for others it might be that time of month... ;-p

With taping the shroud, I'm not surprised that fixed it, airflow and cooling are fickle things. It actually got me to wondering if that might be a partial issue with undercooling some of us see.

The efficiency of a fan blade to move air is greatly affected by a number of factors, one even being the design of the tip. You can greatly increase (or decrease) the efficiency by how the shroud is spaced from the tip (or if you even have a shroud or not). If the shroud is spaced too far away (or if you don't have one) it can greatly reduce how much air the blade moves for a given rotational speed. That is due to turbulence introduced at the blade tip which can reduce how much air is moved, sometimes by a great deal.

With the spacing of the shroud being off by that much, you're going to see too much air being sucked in from the engine bay and bypass the radiator. That is going to greatly reduce the cooling efficiency of your setup. For peak efficiency not just having a close fit, but actually making an air tight seal between the radiator and the shroud would be necessary. To further increase efficiency you would want to tighten up the clearances between the fan blade tips and the shroud and make sure the shroud completely matched up with the dimensions of the fan blades (as it stands now, they aren't that tight and some of the rear edge of the tips are stick back from the trailing edge of the shroud).

But that would need the engine to be incapable of moving in relation to the radiator, otherwise you'll end up with damage to the fan blades or shroud.


I think it'd be interesting though to see how much better cooling we can get by simply sealing up the shroud to radiators fitment. Just a thought anyway, sine I have no way of checking mine right now since it is still waiting at the dealership an hour away for a heart transplant.

Sent from my Nexus 7 using Tapatalk

 

[rascole]

Not trying to be a douche but every H3 with a body lift should be over heating then based on those assumptions. They have to have the fan shroud rotated up right? That is half of the shroud gone now, that is far more likely to be an issue than the 1/2" gap on the top and bottom.

 

[amrg]

Not trying to be a douche but every H3 with a body lift should be over heating then based on those assumptions. They have to have the fan shroud rotated up right? That is half of the shroud gone now, that is far more likely to be an issue than the 1/2" gap on the top and bottom.

From my experience the H3 Alpha ran abit hotter after the body lift. I could tell so as I started to hear the clutch fan roar as opposed to it being completely quiet before that!
I had the shroud trimmed though, not rotated.

 

[rsc]

I'm not going to touch the body lift angle, but think about the gap he had between the shroud and the radiator. The radiator and a/c condenser create a restriction to the air flow through the fan, maybe 600 cfm. If the shroud is not sealed up against the radiator it will pull less restricted air in from the gap around the sides. That less restricted air flow comes from the already hot engine bay, this air is not passing through the radiator fins to cool the engine although some clean air will still make it through the radiator fins. I have not played with it myself, but have seen several manufacturer references to correctly setting fan location within the shroud so I believe there is at least a kernel of truth to that regarding efficiency.

 

[Hopkins86]

Hey guys I installed the pcm on nc fan kit on my h3 and I don't like it at all

 

[rascole]

Seems to be the consensus. Still wondering why there is an issue with the factory fan.