Nice post. I'm very interested in the possibility of adding horsepower and reducing engine temps with a mod like this.

My 1991 Dodge B350 will eventually become a conversion van complete with solar panels, auxiliary batteries, and maybe an upgraded alternator. So this e-fan mod might be something to consider as well.

What sort of gains should somebody expect from switching to electric fans? What are the benefits and drawbacks of each setup? Is there a specific fan recommended by most people for maximum cooling efficiency?

Wouldn't it be more beneficial to install a more passive solution like an upgraded radiator? What about some kind of scoop to direct more airflow into the radiator?

What about doing a radiator flush or installing a radiator cap rated for higher PSI?

From what I understand, a higher PSI radiator cap will lower the boiling point of your cooling system. Antifreeze also lowers the boiling point of your cooling system, it also lowers the cooling efficiency. By switching to a higher PSI radiator cap you could use less antifreeze and more water, which would help your radiator do it's job, cause your electric fans to turn on less often, which would reduce the drainage on your electrical system and finally cause your alternator to rob less hp from the engine.

I'm no mechanic, I just like reading about these things. But that sounds like a pretty cheap HP/MPG gain to me. Just remember that a higher PSI radiator cap will not raise the freezing point in your cooling system. So this wouldn't be a good idea during the winter.

 

Gains, frees up some hp, cleaner look, easier access to the drive belt and accessiorys. Also can be made to run full speed even with the engine at idle in hot stop and go traffic.

Efan benifits descriped above. Draw backs include fan motor burnout (especially if using an aftermarket fan and not a OEM type fan system). Possible over extending of voltage supply if on a lower amp alternator setup. Most vehicles with factory efans do not have this problem.

Clutch fan benifits, simple system, fully automatic, freewheels at highway speeds. Tried and true technology. Drawback include using more hp than an efan in most cases. Noise of it engaging and moving the air, not sure if it would be more noise than the air flow of an efan. Also harder to detect when the clutch portion is failing. Also can take a water pump out if the clutch has a bad bearing or fan blade.

I have a dual core radiator and OEM type replacement fan clutch in my van. Even in the Texas summer with stop and go traffic with my AC on max in a uninsulated cargo van my engine stays nice and cool with engine temps between 187 to 200 depending on outside tempatures. So yes this does help in keeping the tempatures down.

I have not tried to add a scoop to mine and not sure it would make much difference for there is not many places for the air to bypass the radiator. You might try adding black silicon baffel material around the radiator opening between there and the grill but don't hope for much improvement verses exspendatures.

Depending on how bad the cooling system is would play a factor in what type of flush you would do. In my case my van even when it needs the coolant topped off only gets 50/50 premix or if needed a 50/50 blend using only distilled water with the concentrate coolant. I never use just plain tap water unless I am just flushing out the old coolant. From my experience plain tap water can be harmfull to a cooling system.

Higher PSI cap can improve the boiling factor of the system but on older systems it may be too much for the older parts that may have been abused to handle. While I have considered trying it a few years ago so far my cooling system is working very well and I see no need to even bother for that reason. That said I may still try it for helping to eliminate the infamous Magnum Engine Ping that these engines do suffer with. I hear it works for that but have not tried it yet.

Sorry but it raises (good) the boiling point not lowers (that would be bad) it. Yes antifreeze does help to raise the boiling point as well though it lowers the efficiency by about 20 degrees.

Please do not go less that 50/50 mix. Having more water than that will cause severe corrsion in you engine and shorten the life of it and or the radiator and heater core. Also it will bring up the freeze point to less than -34.

 

Very well said. So far, in the Miami heat, with AC on full, in traffic, I have yet to see anything over fan switch temp rating. Soon as they turn on, temp holds or goes down.

 

Corrosion will happen if TAP water is used. Using Distilled water after a good flush will keep the cooling level in top shape. In the north, a 60/40 mix is ideal to prevent freezing below -10 in January in Buffalo, NY or along the Great Lakes that received those dreaded lake effect -minus wind chills.

 

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