Cooling issues? Not anymore

The man, the myth, the legend. @tonered

 

As a general life rule, I ALWAYS trust engineers who make the "because I'm an engineer and I'm smarter than you" argument. Never once ran into an engineer who was wrong in this scenario...

 

The tests that I have seen included comparisons to clutch-fans, and there was still a significant gain.

 

Thanks!

 

Unless you're running 9/10ths at high RPM the average Chad or Cheryl won't notice the difference.

 

No. They won’t.

I have no doubt that it increases cooling. My concern is when the engine shuts down temps soar, fan comes on while your working, shopping, having a cool one, etc. at 12V, 830W is 69A that will kill a battery quickly!

 

That would be an incorrectly wired fan system then. Mine is Engine off, fans off.

 

It does drop off pretty quick. But when it’s around 0F or below it takes a little while. While I do understand that the engine will be under more load, it’s still a lot of air movement on the engine which doesn’t help at those temps. It makes sense that it drops off once the clutch warms up a bit. But I suppose I haven’t had a clutched fan apart to see how it works and what would make it do that at cold temps.

 

Not buying that the fan on our V6's is eating 30hp. Sure, some fans on some engines, but not with ours. I'm a fan of electrics myself, but feel no need to change what I got now because it works. My exp is electrics work best at idle and that's where the manuals are the most inefficient. At towing or cruising RPM's the manual works much better than almost any electric, hence why they eat more hp. On my 78 bronco that does trail crawls in the AZ desert, I went electric. For towing my travel trailer with my V6, I will stay manual.

Side note. Was there a fan in front of the fans in the dyno? I know of no car that doesn't get pushed thru air when running down the road. Would this not decrease the HP needed to spin the fans?

 

There is a large HP difference between this engine and the same engine but in the Camry. The Camry is FWD. I am not an expert but perhaps the fan explains some of that difference. I am not sure if the Lexus RWD variants have e-fans.

 

Wut you talking bout Willis?

 

Some cars have fans that continue to run after the car has been shut off to cool it. Usually they only stay on for a little bit after shut down. Sometimes those triggers would fail and the fans would stay on till the battery ran dead. Saturn SL2 was a perfect example of this, On mine I cut the wires to the fan after the sensor failed and wired them to a manual switch.

 

You seem to not understand what a TSB is. But just because it's under warranty doesn't mean that it'll be free like if you had an aftermarket winch bumper winch etc. they can say that's causing the issue and decline warranty thus you are left to pay. Hence why I said may not be free.

A TSB is a technical service bulletin. It's used as a hey tech we are seeing this as the common cause to this complaint you may want to look here first but it by no means says that's the cause or the correct repair. Techs use TSBs in the independent shops all day everyday on vehicles that are outside of warranty and use them to repair vehicles same goes with dealer techs.

 

Well its something.

So how is the pusher different from the puller, in that the air has to go around the fan in either situation. Is the difference the distance of the fan from the radiator on a pull vs push. So is the difference in shroud on front vs back. So is that really the difference maybe? If anything we know that the air exhausting the radiator is hotter, therefore less dense, and therefore needs more exit area than entrance area to minimize air drag.

Actually that is pretty simple to prove to yourself on your own that the Earth is curved, but I do know you are just in jest... But remember that I didnt come and make an absolute statement on the board about the earth curvature...

I know a customer asks an engineer why A is better than B, I always expect them to say 'You are talking to a engineer'.

Glad you know you are being a smart ass, I was seriously just trying to learn why it was better to pull than push...

So that data is interesting... So obviously this data doesnt indicate anything about a fan motor blocking out the radiator (that you mentioned) and indicates that this particular motor pulls air more efficiently (~10% or so). I wonder how the test was run, reversing motor current or flipping fan blades around... I wonder if the difference is primarily shroud specific, fan specific, or both.

 

The TSB may not be the ideal solution, but i'd sooner PAY to have that done vs. throwing on a total electric fan conversion to solve a problem that I don't have.

Why would I do this? It's a lot easier to sell something stock vs. stuff that's had fingers in it. Some people have a hard time accepting this the majority of people don't want vehicles that have been modded.

 

Puller fans are significantly more efficient. They pull more air and it also allows more natural air to enter the radiator

 

Think of it this way. If I was standing 4 feet in front of a door and you were sprinting to get thru it and into the room could you duck around me and make the single door way. Or if I was standing 4 feet inside a doorway and you sprinted thru and juked one way or another either way you in the room. I wise I could draw on here. But all of this convo is related to moving air when the vehicle is in motion and the air has a natural velocity

 

Also, visualize how turbulent the air is crossing the radiator fins when measuring push vs. pull.

The more turbulent the airflow over the radiator fins the lower cooling efficiency it will have. If the airflow has to travel over/through the electric motor & blades you have seriously turbulent airflow.

 

This isn't for those of you that want to keep things stock its for us enthusiasts and most of us very much know the dilema in selling non stock vehicles as well as buying.

 

I had a guy try to argue that due to the higher amp load at the alt it then took the HP away from the loss of a clutch fan. It was entertaining listening to the thought process of an engineer that showed the HP it took to create X amps for an electric motor. Not realizing that the alt is driven at a constant and it's all electronically regulated. He couldn't get that through his head that no matter the load on the alt it never changes the load on the engine (unless it's one of those weird clutched alt.).