Radiator/fan question

[Rickster]

I replaced my old 3 core radiator with a new 2 core one and also replaced the homemade electric fans the PO had installed with a new Flex-a-lite setup to help with an overheating issue. I now have a gap between the fan unit and radiator because the new radiator is thinner than the old one. Any suggestions on how to close the gap? Is it necessary? I do not think the flex-a-lite frame can be cut down without getting into the fan. The Jeep is no longer overheating.

 

[harleydragon]

they make spacers for this purpose..check this out..
http://www.summitracing.com/int/search/product-line/flex-a-lite-mechanical-fan-spacers

 

[Rickster]

Thanks for the link harleydragon. Looks like these spacers are for a mechanical fan setup after removal of the fan clutch. The Flex-a-lite setup I have are the electric fans. I think that the electric fan housing should be up against the backside of the radiator for efficiency--but since the replacement radiator is thinner there is a large gap between the fan mount and the radiator (if I had replaced the 3 core with another 3 core the fan unit would fit up against the radiator). I am just thinking if the Jeep is not overheating even with the loss of cooling efficiency of the fans if I should worry about the gap?

 

[harleydragon]

okay..when you said flex-a-lite I thought you were talking about the aluminum,no clutch fans that mount to the water pump..in your case I would say use some foam or rubber..my electric fans sit directly on the fins

 

[Hedgehog]

If the motor isn't overheating, other than for a very neat install, the motor is telling you it's happy the way it is. Here's a thought, with the fan against the radiator the area directly in front ofothe fan is the only part of the radiator drawing air, with the fan pulled back there is a larger area for the fan to draw air. Other than filling the gap, you might actually be more efficient.

 

[IOPort51]

Would you please showus your breather set up/carb/TBI.

 

[harleydragon]

If the motor isn't overheating, other than for a very neat install, the motor is telling you it's happy the way it is. Here's a thought, with the fan against the radiator the area directly in front ofothe fan is the only part of the radiator drawing air, with the fan pulled back there is a larger area for the fan to draw air. Other than filling the gap, you might actually be more efficient.

normally a gap allows the electric fan to pull air through the gap rather than making it pull through the fins

 

[Rickster]

Would you please show us your breather set up/carb/TBI.

Sure thing IO. I have the HESCO/Mopar MPI kit installed. The air filter setup I purchased through the HESCO site:

MPI Air Filter Upgrade #HESMPIAFK2 | Hesco

I took these photos for a project on a cold winter's day, but hopefully these will show what you are interested in.

 

[IOPort51]

thats interesting, thank you.

 

[Posi]

Is it possible to trim the shroud so it sets in closer to the radiator? You would need to set up new mounting points but it looks like you could gain an 1" or so. Just a thought.

 

[Rickster]

Is it possible to trim the shroud so it sets in closer to the radiator? You would need to set up new mounting points but it looks like you could gain an 1" or so. Just a thought.

Posi, went out and looked at the shroud again. Looks like to cut the shroud enough to fit into the radiator mount I would be in the fan. Plan to pull the fan assembly next weekend in order to get a better idea on the measurements. Thanks for the suggestion

 

[IOPort51]

Your radiator must be very thin if you have room for the electric fans and a gap like that. I have a heavy 3 row, the core is almost as thick as the bucket. I had to put mine on the outside. There was not enough room between the fan and the water pump.




but, to the point, if it isn't broke, do not fix it. I need all the cool I can get off road but if yours runs cool try it for a trip or two, see if it works as well as you think before changing things. then you know that the change was a good idea.

 

[Posi]

I mounted my fan by drilling some holes in a piece of aluminum then attaching the shroud to the radiator using rivets. Just another option if need be.

 

[Rickster]

Thanks to all for your help and suggestions

Think I will leave it be until I can put it to the test of the heat of next summer.

 

[ThisGuyUKnow]

I mounted my fan by drilling some holes in a piece of alumyou raisinginum then attaching the shroud to the radiator using rivets. Just another option if need be.

any particular reason you choose to mount that contour fan upside down? I see you retained the resistor, what are you using as a controller? in the past I have ditched tge resistor and used a flexalite variable speed control. this time around I am building a fuel injection setup where the ecm can control the fans. it has a primary and secondary activation relay. my original plan was to wire it so that one fan ran off each switch, can I use that resistor to instead run both fans of the primary relay at a low setting and the secondary relay as the high?

I just pulled my radiator back out today I want to paint it like you did to make it look nice.

 

[Posi]

I chose to mount the fan upside down to move the resister up high away from mud and debris. I'm using a volvo fan controller with a 2 stage bmw temp switch. I have both fans turn on low speed at 190* and both on high at 210*. The complete package, fan, controller, and temp switch ran me $25 at the bone yard. Very easy to install setup.


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Hope this helps

 

[tarry99]

I replaced my old 3 core radiator with a new 2 core one and also replaced the homemade electric fans the PO had installed with a new Flex-a-lite setup to help with an overheating issue. I now have a gap between the fan unit and radiator because the new radiator is thinner than the old one. Any suggestions on how to close the gap? Is it necessary? I do not think the flex-a-lite frame can be cut down without getting into the fan. The Jeep is no longer overheating.

I would just trim that top and sides out in Aluminum Sheet , Know anyone with a shear and a sheet metal brake? Or in the heating and Sheet metal Business? Easy Project!.......Maybe some 60 series aluminum......in .050 or .060......cut to size and shape and attached with either sheet metal screws or Dzus buttons to your fan frame......polish it up and your good to go!.......And yes you should block off those area's it will make your cold air fan radiator intake system even more efficient!

 

[Rickster]

I would just trim that top and sides out in Aluminum Sheet , Know anyone with a shear and a sheet metal brake? Or in the heating and Sheet metal Business? Easy Project!.......Maybe some 60 series aluminum......in .050 or .060......cut to size and shape and attached with either sheet metal screws or Dzus buttons to your fan frame......polish it up and your good to go!.......And yes you should block off those area's it will make your cold air fan radiator intake system even more efficient!

Great idea tarry99. I found an online metal shop that I just received a made go order cut of T-AMC 304 0.06 inch annealed[FONT=verdana,Arial,helvetica, san-serif][SIZE=-1] [/SIZE][/FONT]stainless steel for another CJ Jeep project. They do small orders, are fast and reasonable--may give them a shot with the aluminum.

Online Metal Store | Small Quantity Metal Orders | Metal Cutting, Sales & Shipping | Buy Steel, Aluminum, Copper, Brass, Stainless | Metal Product Guides at OnlineMetals.com

 

[Turbogus]

normally a gap allows the electric fan to pull air through the gap rather than making it pull through the fins

I agree as air will indeed follow the path of least resistance. Originally I cobbled together a CJ shroud with the e fan that the P.O. had put on and there was WAY too much air escaping without going through the core. This yielded summer temps on this old 360 of 210-220 in the summertime in the cool climate of Oregon.


Thankfully with the help of folks like IO, JeepHammer and others I got a Merc Mystique fan (Contour) for cheap and wired in a pair of Hayden controllers along with a three way switch and I'm right happy with how it turned out. And with that three way override switch I have mounted in the cab the fans can easily bring the temp down to as low as AMC 150 on hot days.









These shrouds mount so tightly flush that I had to bend (with my heat gun) the shroud slightly to get it to fit between the tanks.

 

[Rickster]

Followup on my electric fan shroud-radiator gap issue. I bought 2 strips of aluminum, painted them black and used the rubber edging from the shroud edge. Placed the edging against the radiator and screwed the metal strips into the fan shroud, top and bottom. Now have an almost contained space between the fan shroud and radiator. Thanks to all for your input.