cooling fan

Huck · #1 (**permalink**) 09-23-2003, 06:04 PM

I'm currently using two fan's, a 14" and 8" both of which when crusing at low speed don't seem to keep up with the temperature. This puts a damper on cruzing. They're on a Ron Woods racing radiator and as soon as the temperature starts to go up all I have to do is go for quick cruz at 40 or so mph and the temp drops down. I didn't use a shroud and wonder if it would help. I also wonder what size fan or fans are being used with success in the 180 degree area. Thanks Dave

vettestr · #2 (**permalink**) 09-23-2003, 06:17 PM

Hello,
As shown by temp comming down and being controlable when ram air or at speed your overall system is funtioning correctly. The problem starts when you lose ram air and even with no real load on engine. You need more air flow from fans! The shroud may/should help but create more air flow and problem will be solved.

hcollado · #3 (**permalink**) 09-23-2003, 06:23 PM

It may not be your fans at all. Hell, with that many fans, you can probably vaccumm the road in front of you.

I would check your water pump and make sure it moves enough coolant at idle. I appears to work well when the RPM's come up.

Just my 2 cents.

vettestr · #4 (**permalink**) 09-23-2003, 09:34 PM

I looked at your home base before commenting and guessed it was a little warm on the cruz outside. Easy to prove if hcollado has it nailed for you. When it starts to hit 200 degrees bring RPM's up to your cruz RPM ( I guess about 2K ) and see if temp comes back down to the T-stat or 180. If it does not come down with just RPM then air flow is issue not coolant flow. Just hope you get a handle on it so you can get back to cruzzin ! Don't over look the oil temp as a source to shed or add tons of heat to system.

Huck · #5 (**permalink**) 09-24-2003, 07:11 AM

Thanks for the info. I'll give it atry and see what happens. Thanks Dave

DAVID GAGNARD · #6 (**permalink**) 09-24-2003, 12:37 PM

Huck;

You definetly need fan shrouds,they make a world of difference and will help "create" air flow at low speeds...

Try this,light a cigarette and with your fans off,put it in front of your radiator,the smoke should rise straight up,now turn on the fans and see what it does,now put it right at the top of the radiator and see how much smoke is blow over the top of the radiator and not thru it......

Air follows the path of least resistance,instead of pulling thru the radiator core it will flow over the radiator into the fans and out the back,not helping your cooling any...A fan shroud causes a suction in the front forcing the air thru the radiator....

Try this first and then go on the other remedys....

David

McCobra · #7 (**permalink**) 09-24-2003, 12:46 PM

David,
Do you have any suggestions on how to "seal" the space between a circular puller fan and the radiator to increase air flow through the radiator?
Thanks

vettestr · #8 (**permalink**) 09-24-2003, 01:17 PM

Here is a photo and link to fans I run on a 542 inch Dart motor in Phoenix AZ. I think the photo may give you a few ideas. http://store.summitracing.com/produc...rchtype=ecatx.

McCobra · #9 (**permalink**) 09-24-2003, 04:42 PM

Thanks Vettestr--you gave me an idea

One of the links shows a strip of steel in a circle. Question is id I can fabricate one that will work with my existimg Spal shroud. Will let you know

DAVID GAGNARD · #10 (**permalink**) 09-24-2003, 04:58 PM

Huck;

I once made a real nice shroud out of some plastic.... I do not know what they actually call the stuff,but I got it at a speed shop that handles a lot of dirt track stuff.... The plastic is kinda thick,but very flexible,comes in rolls 22 inches wide by however long you need,cut with heavy duty scissors or tin snips....

Made a circular shroud and pop-riveted the two overlapping ends and then pop-riveted some small home made L brackets to the shrould and then screwed them to the top and bottom flanges of the radiator,fit tight,worked great,weighed probably one pound or less and cost probably 2 bucks.... BTW,the plastic stuff comes in different colors and is about 2 bucks a running foot....

David

McCobra · #11 (**permalink**) 09-24-2003, 05:55 PM

David,
That's my first choice. The plastic would be flexible enough to make a good seal and like you said, be easy to install.
If you remember where you got it, pls let me know.
Mike

DAVID GAGNARD · #12 (**permalink**) 09-25-2003, 11:30 AM

Mike;

I got the stuff from a local speed shop that specailizes in dirt track stuff.... They use this plastic a lot on dirt track cars.....If there are any dirt track racers in your area check with them first,they may have some laying around for little or nothing.... If you order some from a catalog,the shipping would probably be more than the plastic....

Speedway Motors has it listed in their catalog,$17.95 for a 10'x22" roll. They also have it in 25' and 50' rolls. Colors are red/white/blue/purple/yellow/black,take your pick...It is listed as Colored Plastic... Go to SpeedwayMotors.com to check it out....

The local shop here has 100' rolls and will sell any length you need. I bought 10' of black one time to make some mud flaps/fender extensions for my 4x4 ATV,do not like getting real wet or muddy in the cold of winter going to the deer stand or duck blind... Molds real easy and I usually install it with pop-rivets....used the rest for all sort of things,one being the fan shroud.... The shop here sells it for about $1.50 or so per running foot....

David

McCobra · #13 (**permalink**) 09-25-2003, 07:04 PM

David,
I think I am going to try it. Sounds like a lot easier to fabricate than out of steel or alum.
Thanks a bunch for the lead.
Mike