Will a new flex fan help cool the engine off???

[57wagon]

Just have a quick question,,, has anyone had any experience with those cool guy flex fan's they sell at the parts stores??

I have a 57 wagon with a 350 bored .40 over mild cam, stock heads.. Nothing to outrageous and it runs great... While driving it at speed it runs about 190 to 200 depending on the temp outside.. But after I come to a stop, get stuck in traffic, or idle for a while it creeps up to about 230 and above...

Currently it has a stock steel 4 blade fan on it and an electric pusher fan runnin in front of the radiator.. There is no fan shroud on the car ( should I get one? )

I'm wondering if I should go ahead and see if the six blade flex fan would help, or are they pretty much just for looks???

Thanks,

steve

[40StudeDude]

Get A Hayden electric fan...they are probably the best...pricey, but they work...and get a shroud on that radiator...don't get a flex...they aren't any good at high speeds...they tend to flatten out and quit moving air..pusher fans don't do much for cooling either.

R-

[smittyshotrods]

I would say yes to the shroud and try to get the fan within a inch or so from the radiator. What thermostat you running? I would suggest a 160-180 at most. Others things to check--timing and radiator cap.

[Slide]

Your steel blade fan should cool the engine better than a flex fan... if it's one of the 6-blade style ones. I had a flex fan on my car, then switched over to a fixed-blade fan and dropped my temp about 3-4 degrees.

Flex fans flatten out as engine speed increases, therefore supposedly they use up less horsepower.

How do you have your electric fan wired? With a thermostat, or a manual switch? You might try turning the electric fan OFF at speed. Some electric fans don't move enough air to keep up with what is naturally flowing over your radiator at speed, so they actually impede airflow on the hiway!

And I'd get a shroud.

[57wagon]

I have the electric fan mounted in front of the radiator wired to a toggle switch that is inside on the dash.. I keep it off until I see the temp get up above 210 then turn it on.. Actually I don't know if it helps that much though????

I'll have to measure the fan distance tonight when I get home, I'll try to find a shroud for it, or try and see what that will do...

I am running a 180 thermostat in the car now... Just curious what would the radiator cap do for this???

[marq]

i have a plastic flex type fan on my 350 and it never ever goes over 170,i got a nice big rad though but when you rev the engine from the outside you can really feel it draw air also it draws a lot of air at tickover ,rev the engine and watch it flex .i think it's a 6 blade type and it looks metalic and oldish i will find out tomorrow what make it is,it is an American make though and it works real well......Marq

[57wagon]

Thanks marq,, I had the stock radiator re-cored so it should be good to go??? It came stock with a 283, now with the 350, and the tranny lines are going through the radiator too... Maybe I could try to install the shroud, external tranny cooler (TH400)....

Just don't want to over-do something that isn't going to make a difference...

[ShortBus]

I ran one of those dual 12" electric puller jobbies (2500 cfm) on my junk and it would still get hot sitting in traffic. There was very little improvement over the flex fan that I started with.

I added a high flow water pump which gave me about 5 degrees at idle, then later I swapped back to a mechanical (stock) 6-blade fan (junkyard) with a clutch (parts house) and got another 5 degrees or so at idle. That's with no shroud.

I've heard that a properly set up shrouded fan, -fan an inch from the radiator and about half the depth of the fan hanging out of the shroud, will yield about a 10-15 degree improvement.

[manyolcars]

I have a 57 wagon with a 350 bored .40 over mild cam, stock heads.. Nothing to outrageous and it runs great... While driving it at speed it runs about 190 to 200 depending on the temp outside.. But after I come to a stop, get stuck in traffic, or idle for a while it creeps up to about 230 and above... >>>>>>>>>>>>>>I have a 57 wagon with a 300hp crate 350, stock, no mods, I followed the instructions in the crate for harmonic balancer, carb, flexplate, timing, blah, blah, new water pump, new thermostat, NEW radiator, new hoses, blah, blah, While driving it at speed it runs about 190 to 210 depending on the temp outside.. But after I come to a stop, get stuck in traffic, or idle for a while it creeps up to about 240 and above... There is NO way I could get a full shroud with the 16 inch fan, so I went to a thermo controlled puller fan, large, good quality--it still runs too hot. I've run SBC for 27 years and NEVER had one run this hot. I've tried a lot of things including Chevytalk.com. Is it the 57 front sheetmetal that causes it? I've run with the hood off-no help.

[C9]

If you have a centrifugal only distributor or your vacuum advance vacuum source is selected to ported vacuum more than likely that's the cause of your overheating.

Run a vacuum advance distributor, select the vacuum source to full-time vacuum (drivers side bib on a Carter/Edelbrock) and time the engine properly.

[57wagon]

Is sitting in traffic at 230 degrees going to hurt it?? As soon as I start driving it cools back down to around 200.. So it seems more like an airflow problem to me...

I also have a 24 Tall T that I traded my bike for, it too has a small block in it ( sorry guys I didn't build that one) stroked to a 383 dual quad tunnel ram, eligedly dyno'd around 500 - 600 HP and I can't get that car to go over 160...

One extreem to the other.....

[57wagon]

[ QUOTE ]
If you have a centrifugal only distributor or your vacuum advance vacuum source is selected to ported vacuum more than likely that's the cause of your overheating.

Run a vacuum advance distributor, select the vacuum source to full-time vacuum (drivers side bib on a Carter/Edelbrock) and time the engine properly.

[/ QUOTE ]

When I was gathering parts for this car I came across a mallory hei distributor, vacuum advance brand new.. That is what is in there now..

Running an edelbrock carb with the dist hooked up to a vacuum port on what I remember to be the front passenger side of the carb....

[C9]

[ QUOTE ]
Running an edelbrock carb with the dist hooked up to a vacuum port on what I remember to be the front passenger side of the carb....


[/ QUOTE ]

Move the vac advance hose to the drivers side and plug the pass side bib.

Double check timing to make sure the vac advance is working.

I'm betting your overheating in traffic problem will go away.

[57wagon]

cool I will swap that tonight, and check the timing....

[DrJ]

Check that timing with the vacuum disconnected and the bib plugged. THEN plug the vacuum advance in. The idle and advance should jump up, probably high enough that you can't read it anymore on the timing cover scale, but that's alright. Just turn the idle speed screw down if it's too high. You need around 25º advance total, (with the vacuum advance hooked in) at idle to keep from overheating. Manifold vacuum will do that.
Just do like C9 said.

If it's a newer "smog" distributor the vacuum advance may advance too much. if it moves more than about 12-15º you can either change it to an older unit of put a piece of tubing on it's rod to restict it's travel.

[zman]

I have always had good luck with flex fans. Especially when replacing the shitty four blade Nailhead fans from the fifties. I also have one on my '59 Pickup. The straight six ran a little warm in traffic so I threw a flexfan on and it cured it. I always try and use a shroud if one is available. I also place the fan about 1/2-3/4" off of the radiator. Haven't had an electric fan on the Buick either and it ran great with the 364. I like them...

[JimC]

The flex fans WILL cool your engine.
So will your steel fan.
You only need the fan at low speeds or in traffic
You can run with out a fan above 35 or 40 miles per hour. That is when there is enough air forced through th radiator to cool.
I believe your problem is the fan in front of your radiator which retards prevents sufficient air flow through the ratiator.
It is acting like a big piece of cardbord or other material preventing air flow through the cooling fins.
A shroud will aid the fan in pulling air through the radiator instead of from around. But the electric fan in front of the radiator is slowing airflow.Believe it or not.
I know from experience! http://www.jalopyjournal.com/ubbthreads/images/graemlins/blush.gif
Jim

[57JoeFoMoPar]

I'd say your best bet is to put a good fan shroud on, and use the pusher fan in conjunction with the mechanical puller fan off of the engine. try to find an enclosed fan shroud, like what would have been factory on a chevelle or something, though those JC Whitney $25 chrome deals are better than nothing. I have a 383 Chrysler engine in my 57 Ford, and I'm still ironing out cooling issues. I was talking with a HVAC guy (who has a really badass pro-street Willys), and he says that a puller fan is 25% for efficient than a pusher, and that if you run a shroud, there should be a 3/4" gap between the the front of the fan, and the end of the shroud. I tried the guy's advice and it really helped, still not perfect, but way better then it was before hand. I have a big 3300 CFM electric pusher fan with s-blades on the front of my radiator, which helps a lot, especially at low rpm's where the mechanical fan may not draw enough air. If those real expensive electric fans from Jegs are too much, hit the boneyard for mid 80's to early 90's audi's. They use 2 fans with interlocking blades for more surface area on the radiator. As for flex fans, I'd recommend the stainless steel Flex-a-lite 6 blade fan. The blades flatten out at high rpms as to not rob as much horsepower, and most importantly the fan is rated to 10000 rpm. I know guys who have had blades let go off of cheaper flex fans, and we know the consequences of that. I also installed one of those high flow thermostats from Mr. Gasket. From my own personal experience, using the flex fan with a shroud, electric pusher, and high flow thermostat yielded a very impressive improvement in my cooling system. Best of luck

[warbird]

In my experience, the key to correcting an overheating problem always has boiled down to the radiator. I've tried the flex-fan, electric fan, shroud routine on several small-block Fords and a couple of other motors over the years. While they all seemed to help a little bit, the only way to get the low speed heating problem under control was a larger radiator or one with more rows in the core. Fought this problem with various motors in a '64 Falcon Sprint, '66 Mustang and '59 Willys. Wasted a lot of time and money on fans, shrouds, cooling additives, boiling radiators out and the like. A better radiator always solved the problem. Just my experiences.

Try swapping the vaccum advance source as C9 says, I've heard of this working on sbc's before.

Good luck,