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Red Fan vs. Yellow Fan

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Stinky

Stinky

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Does the Red coolong fan cool the engine better than the older yellow fan? Looks like it is designed better with more blades.
If the red one is indeed better,...Is there any reason why I should'nt replace my original yellow fan with a Red one on my 71' TR6?
It would fit,...right?

I was thinking about going to an electric fan setup,...but I thought maybe an upgrade to a red fan might get the job done, and look more appropriate.
I would hang onto the original fan for future reference, so the car could be put back to original if need be.

Thanks
 
The red fan does indeed cool better, because it had more blades, though you probably won't notice a difference. It's a good idea to put an electric fan on too, though. They're good insurance incase you ever get stuck in traffic, and the car definitly will overheat if you do get stuck. You can get several different size electric fans at Advanced Auto or AutoZone, or one of those car stores and they just attach to the front of the radiator. A wire can then be run into the cockit and a switch put under the dash to turn it on and off, or a thermostat be fitted to turn it on and off automatically. One of these is going on my 6 soon.
 
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and they just attach to the front of the radiator.

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If by this you mean the type that has some sort of plastic fasteners going through the radiator core, they will likely, over time, wear a hole through the very thin (about .004 inches thick) radiator tube walls. The mass of the fan assembly WILL vibrate against the radiator a bit. Much better to use some good solid brackets to the surrounding sheetmetal.
D
 
Tom,

One of the first things I noticed is how loud the stock red fan is, it didn't take much convincing to hatch a plan to get rid of it.

I'm working on an electric fan setup as I write this. I've got a 16" 2200 CFM permacool fan that should cool any TR6, this particular fan bolts to the side of the radiator with machine screws, so there's no need to use those plastic ties that will eventually ruin your radiator. I also have a connection to a guy that makes a fan eliminator kit, which is basically a round plate/bolt that replaces the fan mounting thingy on the crank. All thats left is to fit a fan switch that will cut it on/off at the correct temps. I'm told Napa sells a good one.

Let me know if you want any of the details and I'll provide all the information that I've accumulated so far.

-Shannon
 
Well, I use the yellow original fan on my '72, and have never overheated (though the temp does rise) in terrible rush hour traffic, in Dallas, when it's 100+ outside. If you have an overheating issue, then perhaps there are other problems, such as thermostat, clogged radiator or engine passages.
 
I don't think there is any problem with putting the later fan on an earlier car, only that the later fan is supposed to be virtually impossible to find. The few I've seen on Ebay and such have been missing a blade or something like that, and they still wanted quite a bit for them.

I'm planning an upgrade to an electric fan this spring myself. In my opinion, if your car is not a show car then an upgrade to an electric fan is a wise choice, especially if you live in a hot climate. I have made several upgrades to my car in the name of performance/reliability in the last two years, and this is a good one. In the vintage Mustang community they call this "resto-mod", I'm sure they call it this or something similar in the LBC community as well. So far I've done an upgrade to the Pertronix ignitor and matched coil, very nice mod. Not having to play with points has been a godsend as I hate them. I put the ignitor in almost two years ago and haven't touched it since. I've also done an electric fuel pump, if anyone wants some ideas on that I can provide them in another thread as I went a few different ways before coming on the present setup. I have part numbers and sources for that stuff.

Anyway, to the cooling fan specifically. I'm going to go with something similar to what lastdeadlast is talking about, a fan large enough that will bolt directly to the rad perimeter, in puller orientation. Get the biggest fan you can that will physically fit over the rad and between the rad and the crossmember, and not overload the cars electrical system. Places like Summit racing or any good hotrod shop will have lots of choices, with specs. I will remove the factory fan altogether, as I have heard also that it is immensly quiter under the hood without it and it really doesn't work that well anyway. Also, there is a BMW thermostatic switch that will work well, and a fitting for it can be brazed into the radiator or a holder can be made to fit into one of the spliced rad hoses. This is a 180 degree t-stat switch if I remember correctly, and will kick the fan on and off automatically. Additionally, there is a three position switch in the cockpit for manual override, on, off, and auto. I have an article that someone wrote up with this very setup (where I got the idea), with part numbers and wiring schematic for everything, if anyone is interested I can dig it up.
 
Lastdeadlast,

Yep, thats the one. Thanks for finding it, you saved me a trip into the mess that is my desk looking for the hardcopy I printed some time ago. The only thing about this is I don't know if I want to mess with my rad having the threaded fitting for the t-stat switch brazed in. My buddy who has a shop and is a good welder said he can make me up a short length of stainless pipe that is the same diameter as the ID of the upper rad hose. He can then weld in the threaded fitting for the switch into that. Then all I have to do is cut out a small length of my upper rad hose for the pipe to fit in, seems like that should work dandy. The only other real fabrication that has to be done is to make a new attachment for the water pump pulley, since the factory fan and fan extension will be gone. I think if you can find an extra fan extension you can just cut it down to the neeed length. There's a guy an ebay that sells them, but he makes them himself out of billet aluminum and he wants a decent buck for them. That might be nice if you already have lots of shiny stuff under the hood (er...bonnet).

Scott
 
My tr6 has a red fan. If you are thinking about putting the electric fan onto you car you should put one on there and take the factory fan off. Taking the factory fan off will give you a little bit more power out of the engine. Putting the electric fan on the back of your radiator so the radiator gets fresh air. The electric fan can pull air and also cool the radiator down. On the trip out to Richmond last summer in a TR4 with an electric fan and no factory fan we ran most of the way without the electric fan on except when the temp. started to climb. If you look where all new car fans are at they are all on the back of the radiator.
 
I agree with Paul that it is questionable how useful an auxilliary electric fan is and how much they really cool. I have been the route of mounting a "pusher" fan in front of the radiator, not wanting to shorten my fan extension and eliminating my stock fan. There is some question about how much an electric fan assembly actually blocks radiator flow and reduces cooling under certain conditions. I removed the fan, went with better (aluminum) shrouds from GoodParts. Then I sent my radiator off to a quality shop whence he converted the stock radiator to a three row, added Water Wetter, and no more problems. Yes, the temp rises in traffic on a hot day but never to the danger level. Why add more gizmos to accomplish very little? Too, I added an oil cooler to reduce the temp of the oil, mounting it with a bracket from Earl's that I adapted to my oil radiator. (You can almost lift the front of the car with this setup, very sturdy. I've seen stock mountings vibrate a crack in an oil radiator and wreaked havoc.)
I believe the K.I.S.S. rule applies here.
Bill
 
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There is some question about how much an electric fan assembly actually blocks radiator flow and reduces cooling under certain conditions.

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I agree... My TR4 has a pusher electric fan. The original fan is gone. That's the way I bought it. The electric fan works great at low speeds and in traffic; however, I do see the temperature rise at higher (interstate) speeds. I have long suspected that the electric fan is actually hindering air flow at this point.
 
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I agree... My TR4 has a pusher electric fan. The original fan is gone. That's the way I bought it. The electric fan works great at low speeds and in traffic; however, I do see the temperature rise at higher (interstate) speeds. I have long suspected that the electric fan is actually hindering air flow at this point.


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Well, this is why I believe it is extremely important that, in this application, the fan be mounted in the puller configuration. This of course requires the removal of the stock fan and alteration of the fan extension, which i can understand why some may not want to do this. However, I would be willing to bet money that a properly configured electric fan (meaning a puller) is capable of superior cooling over the stock setup based on the CFM ratings alone. The biggest advantage to using an electric is that the fans rpm is not dependant on engine rpm, thus you have the same CFM capacity at idle as you do at speed.
 
I have the original red factory fan on mine and in 25 years I've had the car, it's never overheated. I can be sitting in traffic near 100 degrees and the temperature hardly rises. Interesting to hear everyone's opinion on it.
 
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I don't know if I want to mess with my rad having the threaded fitting for the t-stat switch brazed in. The only other real fabrication that has to be done is to make a new attachment for the water pump pulley, since the factory fan and fan extension will be gone.

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I didn't want to mess with that either, especially since I wasn't planning on converting to fuel injection as that author did. I installed the Permacool as a puller with the probe thermostat and it works great. DO NOT USE THE ZIPTIES TO MOUNT THE FAN THROUGH THE RAD!! Additionally:

1. Dry fit the fan with the rad in the car to be sure you have enough clearance between the back of the fan motor and the cross brace. On mine, that clearance is less than a quarter inch.
2. Buy the CNC aluminum fan eliminator kit (spacer disk, shortened crank bolt, lock washer); for $35, it's the way to go.
3. Consider upgrading to the 60-amp Bosch alternator (and easy upgrade that I'm happy with). The fan draws about 10 amps which can be a problem with the stock Lucas alternator.
4. Direct wire the fan T-stat to the positive post of your battery using the fused lead and run the switched lead to the cockpit for manual override. The wiring supplied with the kit is just long enough to run under the wing on the passenger's side AND you won't be drawing those amps through the stock fuse box.
5. Recore your rad to modern specs (3 row?).
6. As others have cautioned, don't install in the pusher configuration.
 
On my 79 Spit I run only an aftermarket electric fan, mounted to the old fans mounting brackets, the 79 came with an electric fan. Here in the summer it typically gets upward of 100 degrees pretty much everyday, and I have never had any overheating problems. I haver a toggle switch on the dash and usually the only times I turn it on is when I am rolling up to a stop light or something where I am going to have to sit for a few minutes. Usually even when the temp is over 100 if I am ddriving along especially on the highway my temp never gets up over the middle of the gauge, about 160 I think. Good luck.
 
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2. Buy the CNC aluminum fan eliminator kit (spacer disk, shortened crank bolt, lock washer); for $35, it's the way to go.
3. Consider upgrading to the 60-amp Bosch alternator (and easy upgrade that I'm happy with). The fan draws about 10 amps which can be a problem with the stock Lucas alternator.


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Hey Rick, would you happen to have part numbers and suppliers for these items (the fan eliminator kit, the alternator I guess you can get anywhere)? Would appreciate it.

Thanks
Scott
 
A few more comments on the Bosch; At full charge the Bosch could easily melt the stock wiring, so I installed an 8ga. wire from a secondary lead on the alternator to the positive terminal on the starter. Also for the older style alternator plugs, you'll need a plug kit (moss part number: 540-280, $6.85). The only problem I had was messing with the spacers on the alternator mounting, I even use the the stock fan belt.

With 60 amps at your disposal, you should be able to run about anything you'd want.

-Shannon
 
I know that the TR2-TR4 engines (and I'm pretty sure the TR250-TR6 are the same) are designed with the fans as a part of balancing the crank, and removal of the fan will eventually cause vibration and POW! (Although, I never have heard of anyone actually experiencing this -- and overheating will ruin your engine quicker.)

But something to keep in mind.
 
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Also for the older style alternator plugs, you'll need a plug kit (moss part number: 540-280, $6.85).

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On my '72, I had 2 different size plugs going to the Lucas alternator (a 3-wire setup). When I fitted the Bosch, I simply pushed the male spade terminals out of the old plugs, insulated those spades with heat shrink tubing, and pushed them on the corresponding Bosch lugs. Don't forget to heat shrink the unused threaded terminal on the Bosch. I also replaced the original alternator adjustment link (the suprisingly thin gauge 'L shaped' metal piece) with one homemade out of thicker stock. The original had developed a crack orginating at the water pump attachment point. Either way, you'll likely have to file the link down in the area above the alt cooling fan blades to clear them.
 
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