Replacing BX fan w/electric fan

[bx24]

Originally Posted by BotaBigot

Technically a neat idea, and that fan looks like it might work. My concern is exhaust and other engine compartment fumes. You would have to run the exhaust far enough back to not be drawn in with the cooling air. And, any gasket/seal leaks on a hot engine could create fumes. I'm guessing you want to avoid the hassle of a heater core. How about some form of electric heat?

BotaBigot- I keep himming and hawwing back and forth whether it would be easier to just go with a core. Going that route would give me a little bit more flexibility on varying the amount of heat, but then I start thinking of how easy this would work if everything fit into place .... we'll see. I have not even considered electric heat because of my perception of how many amps it would take to heat things up enough .... it seems like a waste to not use the "waste" engine heat.

As far as the fumes, I was thinking of just making up a bent pipe in the shape of a "J" to simply go straight up with the exhaust. The other thing I thought I could do was to run the exhaust through the FOPs tubes. I cannot remember what other machine I read about did that, but the concept seems pretty straight forward and I could exhaust it out the back or side up high.

Originally Posted by milkman

I can't tell from your picture, but is there room to put the electric fan between the battery and the radiator and pull air through the radiator from that side? That's if there's not enough room with the engine fan removed, your tractor is newer and different than mine so I can't be of much help comparing the two.

Milkman- I pulled out the battery yesterday and although I was not looking specifically at that, something tells me there is not enough clearance (call it a gut feeling) .... But I will certainly look now (good idea)

Oh and hey, one other thing. Did anyone else not read the owners manual and not realize there was a screen that pulls out vertically right behind the radiator. Every time someone was taking about the screen, I thought they were talking about the black "half moon" screen between the drivers leg. I guess I am fortunate because 300 hours later, there was barely anything on it. That would probably change if I removed the plastic cowling under the battery to suck air from underneath ..... who knew!

[SPYDERLK]

Neat idea, but [drat], what is your alternator capacity? Probably hard pressed to run a 10A fan.
larry

[BotaBigot]

Originally Posted by bx24

...I have not even considered electric heat because of my perception of how many amps it would take to heat things up enough .... it seems like a waste to not use the "waste" engine heat...

I understand your wanting to use that "free" heat, and think you just might pull it off. If it doesn't work out, here are some numbers to consider for electric. BX24 alternator puts out 40 amps. A 300W heater draws about 25 amps and provides about 1100 BTUs (you might not need that much). That leaves about 15 amps for lights, which could be a problem, depending on their draw and how long you'd be working in the dark. Any difference between alternator output and draw would come from the battery...which might be OK, so long as you remember to hook up the battery charger when you put the tractor away...

[bx24]

Originally Posted by BotaBigot

That leaves about 15 amps for lights, which could be a problem, depending on their draw and how long you'd be working in the dark.

The lights are the real kicker here. In the winter, there is obviously a pretty good chance that I will be working after the sun has gone down, and lights will probably be key. I am planning on mounting some low amp running lights on the canopy which should help if I leave the traditional headlamps off.

Another source for electrical draw will be a fan to keep fogging down on the inside of the windshield.

I have never checked, but I wonder what the current head lights draw right now ... that will give me a base line to work from.

What would really be slick here is a variable pitch fan blade .... that would solve all kinds of problems. I wonder if I could make one. It would not be as efficient as the one that is on there now, but as long as it is in the ballpark. Hmmmm

[BotaBigot]

Per WSM, headlites draw 37.5W...didn't say each or both. Assuming each, that works out to 6.25 amps total draw. You should be OK so long as you don't go overboard on auxiliary lighting. Use Watts = Volts X Amps to figure your load.

Variable pitch fans/props are complicated...variable speed might be a better way to go. Careful, you're beginning to overthink your original idea...

[bx24]

Originally Posted by BotaBigot

Careful, you're beginning to overthink your original idea...

Thanks for the amp draw calculations .... right after I posted the variable pitch fan idea, I thought of this ....

What about turning the fan "prop" around? If that would work, it would solve lots of problems. From what I can see, it would be closer to the radiator, but I cannot think of a reason why that matters. I am not sure how much of the dashboard / radiator structure I have to take apart to do any of this, but I if I could do it in an hour, I could afford 2 hours per year.

[B7800mike]

About the fan, with electric fans be careful a lot of them are push or pull. but by now you have already thought of this. About the varying the fan try a rheostat from electronics store. Or if you are really good an auto blower resistor. My suggestion is to get a small heater core and small fan with rheostat and you will have heat. You would need to vent the heat from the cab...... like an adjustable vent or window. hope this helps

[BotaBigot]

Couldn't continue from memory...had to walk out to the barn for a look-see...

No room to mount fan on operator side of radiator. The support structure for the dash/etc. is one-piece cast aluminum, and butts right up to the slide-out radiator screen. On engine side, removing fan blade assy is 4 bolts. Bolts go back in to hold pulley on water pump hub. I see 2 problems: With fan off, clearance between water pump hub and radiator looks to be under 2 1/2". You'd need to find a thinner electric fan than the one in your earlier post. The fan shroud is more than just a shroud. It's also the air cleaner cannister. You would want an electric fan that would fit inside without hacking up the shroud (didn't have my tape measure with me for shroud diameter or water pump clearance).

[SPYDERLK]

Originally Posted by bx24

Thanks for the amp draw calculations .... right after I posted the variable pitch fan idea, I thought of this ....

What about turning the fan "prop" around? If that would work, it would solve lots of problems. From what I can see, it would be closer to the radiator, but I cannot think of a reason why that matters. I am not sure how much of the dashboard / radiator structure I have to take apart to do any of this, but I if I could do it in an hour, I could afford 2 hours per year.

Turning the fan prop around and reversing the rotation will restore efficiency lost from just reversing rotation of directional blades. A lot of work. I liked the idea to just use the std/most efficient direction for the warm season and just reverse rotation in winter when you want reversed flow but dont need as much flow.
larry

[bx24]

Part of me is just being a cheap SOB, but I hate to "waste" HP and thereby fuel if I can get the same solution by reversing the existing fan.

As I sit here and ponder the alternatives, I was thinking that I could pull out the screen in front of the radiator and replace it with a pan (similar to the a cookie sheet without the bottom lip) and although the air would be restricted to only suck from the bottom, I would not be sucking air from the cab. To make up for the drop in cooling efficiency, as mentioned earlier I could install a couple of these with very low amp fans for under $80 for everything. I like these computer fans because they perfectly fit the 120mm fans which are low amp fans and they have easy mounting options.

Hardware Labs Black Ice Pro 120 Radiator (1/2" barbs)

Here is a whole page of choices

Water Radiators and Accessories

After everything else, this may be the best way to go.