Engine radiator fan
- Thread starter ChrisK
- Start date
2old2fast
Active Member
Whether or not to use an elec. or mech. fan may be decided by if you can make an effective size mech. fan fit...on mine w/the engine as high as it is , I wouldn't be able to use anything bigger than about 12" & still clear the upper rad. hose but a 16" elec fits just fine..mine's been trouble free for 14 yrs. & 40K miles.
dave
dave
benT
Active Member
We've run electric on our 3 Ts for two reasons:
1. Space. I don't like lots of extra space or length in front. The electric makes it pretty compact.
2. Safety. Unless the fan is fully covered in a shroud, I don't like an open engine (no hood or sides) rod having a fan that you can get your hand or whatever caught in.
1. Space. I don't like lots of extra space or length in front. The electric makes it pretty compact.
2. Safety. Unless the fan is fully covered in a shroud, I don't like an open engine (no hood or sides) rod having a fan that you can get your hand or whatever caught in.
Mike J
Member
My thoughts exactly, a nice 5 blade non- flex fan is my plan. I'm in S.W. Fl, I know what you mean. Everyone has good points, it's what best fits your build !
Hackerbilt
Active Member
I'm actually building a shroud right now to house a 14" electric fan.
My 454 cooled fine while being driven using a non-shrouded 12" electric but would cook in tight traffic...going into a show or whatever. Used to have to shut her down now and then for safety.
Thats where the electric fan shines. You can use it after the engine is shut down to keep cooling the engine.
Just the same...it has been tempting to go to an engine driven fan for simplicity.
But I just don't like those big blades spinning around like that.
I know a guy who lost an ear to a Ford fan back in the 70's. VERY lucky he didn't get it in the face when it let go while he was trying to find an engine noise leaning over the fender!
Time will tell for me if I made the right choice I guess. Hopefully the shroud doesn't restrict flow while on the road and create higher temps while actually driving. That would be just dandy....
My 454 cooled fine while being driven using a non-shrouded 12" electric but would cook in tight traffic...going into a show or whatever. Used to have to shut her down now and then for safety.
Thats where the electric fan shines. You can use it after the engine is shut down to keep cooling the engine.
Just the same...it has been tempting to go to an engine driven fan for simplicity.
But I just don't like those big blades spinning around like that.
I know a guy who lost an ear to a Ford fan back in the 70's. VERY lucky he didn't get it in the face when it let go while he was trying to find an engine noise leaning over the fender!
Time will tell for me if I made the right choice I guess. Hopefully the shroud doesn't restrict flow while on the road and create higher temps while actually driving. That would be just dandy....
fletcherson
Well-Known Member
In mine, there is only room for a 12" mechanical fan. I plan to run it, but unsure if it will be enough to keep the bbc cool. It has a thick core radiator. I prefer mechanical fans, had too many electric fan failures over the years, but will run one if the small diameter fan won't keep up. I will add that the newer fans seem fairly reliable, as I don't often hear of them failing nowadays... Of course, the failure usually stems from faulty electronic components such as relays or thermostats. My other concern is there are under drive pulleys on it too, I will likely replace them and install a hi flow water pump. One thing I have learned over time is that a properly sized and functioning thermostat makes a big difference in maintaining temperature.
As usual, right now my plans are unusual. I'm planning for a pair of 9" 1050 cfm electric pusher fans, arranged diagonally across the radiator face, sandwiched inside the grille/radiator shell. The radiator will be aluminum, with a 3 row core measuring 19.75" x 13.75. This setup will be providing the cooling for a small V6, with the transmission cooling handled by a separate aluminum radial fin cooler.
fletcherson
Well-Known Member
I would think 30 amps would be sufficient, but check the fan specs. As for placement, most electrics mount very close to the radiator, and come in push and pull orientation, so you can place them on either side of the radiator, many just use plastic wire tie type fasteners that fasten the fan directly to it. I don't like those myself, I prefer a shroud, with the fan mounted to it, but they do work. For a mechanical fan, as long as it won't contact anything, it's ok. The closer, the better, within reason. You have to keep in mind that they flex.
30 amp would be a good fan. It might be necessary on a hot engine. Most aftermarket fans will be in the 20 + or - 5 amps. The amp number is a better indication of what the fan can do, compared to cfm. Some of the factory fans have a 50 amp draw on start up and are multi speed.
Although I have no overheating problems with a generic electric fan on my T, I like the benefits of its full draw while stopped in traffic or parade speeds.
Although I have no overheating problems with a generic electric fan on my T, I like the benefits of its full draw while stopped in traffic or parade speeds.
Screaming Metal
Active Member
What They SAID! If your gonna run a mechanical fan, a shroud isn't totally necessary, but, you have to get that fan close to the radiator to pull air thru. While your car is moving and you have airflow thru the radiator, that fan blade is just along for the ride! Its only function is at really low speeds or sitting in traffic. If you smack into a car or obstacle, chances said fan is gonna eat that radiator alive.
Heres another thing to think about. If, I said IF, you loose a belt, I have seen them get tangled in the fan and take out a radiator and shroud. Probably won't happen to you, its happens very seldom, matter of fact. BUT, do you wanna risk it while a few hours from home on a long cruise? I Love Mechanical fans because of the old style factor....but it someone gets hurt or your rad. gets eaten, the fun flys out the window.
I run a electric puller on the big blue oval motor, along with a electric warerpump. They have got these components to where they are super reliable, and perform well on all performance apps....
The saving grace with electrics is the room they save. Word of warning though....if you run a elect. water pump, just be sure of their protrusion dimension, some of them stick out there and will interfere with a cooling fan. Proform makes some low profile ones that don't stick out....made for the most popular apps....
Heres another thing to think about. If, I said IF, you loose a belt, I have seen them get tangled in the fan and take out a radiator and shroud. Probably won't happen to you, its happens very seldom, matter of fact. BUT, do you wanna risk it while a few hours from home on a long cruise? I Love Mechanical fans because of the old style factor....but it someone gets hurt or your rad. gets eaten, the fun flys out the window.
I run a electric puller on the big blue oval motor, along with a electric warerpump. They have got these components to where they are super reliable, and perform well on all performance apps....
The saving grace with electrics is the room they save. Word of warning though....if you run a elect. water pump, just be sure of their protrusion dimension, some of them stick out there and will interfere with a cooling fan. Proform makes some low profile ones that don't stick out....made for the most popular apps....
Screaming Metal
Active Member
If money is a issue, you can go to the boneyard an pull one off a mitsubishi/nissan/toyota, some of these have nice sized radiators, and attachment is easy. These usually are setup for 25 to 30 amps., and will flow all the air you will ever need, some even have variable speeds (As Per RR!)....instead of just on and off....but you usually have to run the correct temp sending unit for them....
I have found the VW Beetles fans to be excellent, if you can get them reasonable.
In this area, the skies the limit! Choose wisely and smart....And ALWAYS RUN A RELAY!
I have found the VW Beetles fans to be excellent, if you can get them reasonable.
In this area, the skies the limit! Choose wisely and smart....And ALWAYS RUN A RELAY!
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fletcherson
Well-Known Member
You may need to use a diode too. I have had electric fans prevent the car from shutting off, bucause the fan acts as a generator when the power is cut and it can feed back through the system... A diode is an electric check valve, and only allows power to flow in one direction.
Screaming Metal
Active Member
Yep, your right, it can, thats why I run a isolated relay. Once the power is killed to the relay (wired into the ignition switch circuit, ie, turning the motor off), it releases, and the motor stops. Good call....
fletcherson
Well-Known Member
I hear ya, and agree, but I had one that would hold the relay in and prevent the ignition from shutting off. Until I figured out the issue, I had to plan to shut it off when the fan was shut off, lol... That was when I was young and knew everything...then I learned what a diode actually did. I always use relays and like them because you can tap the ignition feed on the high side of the ballast or resistor wire and the draw is low enough, it doesn't affect anything. Some relays come with a diode in them, especially if they are designed to control motors. I was always frugal (cheap) and used salvage stuff, so buying a relay was a rare event....it is likely I had a general purpose relay. Anyone else find it ironic that the older you get and the more you learn, the more you learn you have a lot to learn?
old round fart
Well-Known Member
If you power the relay from the acc side of the switch all is well.
Bowtie T
Active Member
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