has anyone noticed an advantage to mounting an electrical cooling fan as a pusher or puller? i have room enough to do either.
I had one mounted as a pusher, but I continue to have cooling issues...not the fan's fault. I think it works equally well in either position...
If you use a fan as a pusher you will never get more air flow than the fan cfm which is not enough to cool most old cars and the the fan is usually as big as the radiator. Air is going to look for the path of least resistance, at a idle sure it will push 2000 cfm, as you drive down the highway the fan spinning will act like a big 14" disc in front of your radiator and all the air will go around the grill. Puller if you do not run a manual fan.
I have a pusher in front of my radiator with a mechanical fan on the engine. Aux. fan is handy if you get stuck in hot traffic. On the highway, with the fan off, it will generate enough voltage to light the "on" indicator light on my dash. So I know it's turning via air p***ing only. Can find no reason to not use a pusher. What's the difference if its turning under power or turning from air velocity
Yep, pullers are much more efficient, especially if you use it with a shroud so air is pulled over the entire finned area instead of just in the cir***ferance of the fan blades. I think you will also find that a lot of us on here love SPAL brand fans. I was going through a fan a year until I started buying SPALs. The last one I bought was still going strong after 3 years and I suspect the current owner still has the same one on the car. They also move a whole lot of air compared to some brands. Don
I use a 'pusher' in my '35 Chevy as it can't be seen behind the grill. It fits well and covers most of the core. The '46 Olds project is opposite and a 'puller' as I use a shroud with it. A quality cubic feet per minute (CFM) fan is the key and curved blades are better than straight.
They claim pushers are 30% less effective than pullers. But we're talking custom applications here so I can see where either can do the job ..........as others have said.
Big electrics (16") on a shroud in puller configs work well even in Kalifornia. Pullers are worthless for a primary fan.
I must confess that I am anti electric cooling fan. I can't stand them. They are ugly inside the engine compartment or hiding behind the grill with that daglo sticker (watch your fingers) showing from two rows away through the grill. They are just easy that's all. I see an electric fan and think this guy doesn't know **** he just buys parts from the street rod suppliers. My buddy was laughing at me because it cost me 200 buck more to use my mechanical fan in stead of a cheap electric fan. It's a character flaw of mine that I just can't get over. Forgive me if I stepped on any ones toes. I made sure the owner was not looking when I took this picture. I didn't want him to know why I was actually taking the picture.
1old - What ever you do...just DO NOT buy one of those cheezy, thin/narrow bladed, aftermarket fans. Buy a GM, Ford, Chrysler fan. Most factory fans are "pullers" by the way. The factory fans are a MUCH better design, move a larger "volume" of air, and will last longer. JUST looking at a CFM rating isn't going to help...because the aftermarket way of measuring CFM is different than the big three factories method. Two good ones are the Viper and the big (two speed) Lincoln fans. These will cool just about anything. Mike
Pullers work better. Someone said that a pusher blocks the radiator, I don't know if that is true but I do know that a puller works better. I have discovered that when they are off the radiator with a shroud they work better as well, it draws air across the entire radiator and not just when the fan is.
An object(like a fan motor) mounted in front OR behind the radiator will restrict airflow. General rule, fans are more efficient pushing against a restriction rather than pulling on one. It's the internet, so pick whatever answer you chose.
I can see it but I don't have scientific proof of it. better to say that I have no proof than to wait for the '****** bashers to come up with some sort of a formula that proves that I am wrong. Engine man I am on drugs and I still don't know what he ment. I mean hell everyone knows that an electric can't be used for a primary fan at all. That is why the manufatucturers use them; your engine burns up and you have to buy a new car.
You say that isn't true. Although a common misunderstanding, and it seems intuitively so, you are mistaken. No matter where it is in the pipeline, a restriction is a restriction. This is why a pulling fan moves less air than a pushing one. Pulling on a restriction the air is less dense, that lowers the fans efficiency, which results in less air being moved. When a fan is pushing against a restriction it is doing that with denser inlet air. Fans can be optimized for one or the other condition, but in the end a pushing fan can outperform a pulling one.
From a technical standpoint, pullers are better and a shroud will increase its efficiency 50% or more. All the units on submersible US Navy vessels are pullers. Personally, pushers are ugly and even the previous posting of the raspberry colored roadster proves my point.
Al I believe in part where the problem lies in either situation is that the fan is lying right against the coils. For a pusher or a puller to be optimized they must be moved away from the coils and have a shroud built to cause them to move air over the coil. For a pusher to function well in this situation it will have to be running all the time where as a puller set up like this will allow more air to p*** over the coil prior to the obstruction even if it is not running.
You have plenty of company in your ***umptions. You can either do some legitimate research on the the subject(not internet surfing), or continue to do as you wish. Either way, the facts are what they are. I know you made the statement to discredit me and to be a wise-***. It didn't work out this time. I have worn a number of different hats over the years and have worked with many auto engineers. I have been asked to advise auto engineers on many occasions. Yes, I should have better things to do than argue with boneheads on the internet, but I like this forum and some of the people here.
Why not present some of this factual research for us? If you've done it, why not share your vast knowledge with us? I thought that's what this forum was for? Sharing knowledge and information? I'd LOVE to be proven wrong. Give us some airflow charts, please.... I'm open to learning.
Like any engineering problem, the decision to push or pull is full of tradeoffs. In general, however, I am inclined to go with the professional judgement of all of those graduate engineers that design OEM systems; while they may exist, I can't recall seeing a pusher system on a new car. Puller for me, in those cases where I can't figure out how to package the real first choice, which is a mechanical fan.
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