jhcattleco
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Has anyone tried using an electric cooling fan on nhc250 to avoid replacing fan clutch
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Converting m939a1 to electric cooling fan
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On a side note, I’ve got a m931 with the nhc250 I’d sell you the clutch
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Crf450x
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To answer your question, no I haven’t tried it on a 5 ton. But I have tried it with a 5.9 Cummins dodge and seen a few people do the same....it doesn’t work. Mechanical fans move an exorbitant amount of air. Electric fans just don’t.
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Hey heh. I like that. Yes they do and you know it too.
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So can all electric. Most all of the newer transit busses are electric fan only. They do a great job and eliminate the old giant hydraulic pumps needed to turn the fan motors and decrease parasitic load. On the dyno, when the hydraulic fans locked up, there was a noticable HP drop, IIRC right around 30 HP at the wheels on a T drive application. I've also seen all electric on OTR fleet trucks, Overnite Transportation comes to mind. Their fuel milage on the electric fan units was around 11 MPG.
Crf450x
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Well I stand corrected. I’ve never seen one that wasn’t mechanical. Learn something every day.
Turbine Electric Fans for Over-the-Road Trucks and Tractors
Most over-the-road trucks and tractors can replace the conventional belt-driven fan with our 12- & 24-volt turbine electric cooling fan assemblies.
www.electricfanengineering.com
74M35A2
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It can be done, but the belt driven cooling fan on the M939 series can pull up to 15hp from the engine at speed. This is 15hp worth of cooling airflow. You can just hear it roaring, even from inside the cab. If you want to match it's capability, you can't just use something from Summit Racing or whatever. The ones Will are referring to are pretty serious units, and sometimes multiple in layout. Those are going to be way more expensive than a replacement fan clutch, even if new.
It also depends on the climate and load environment you plan to run the truck. If you want to match stock capability, you'll need to move at least stock amount of air across the radiator. Less can be less, etc.......
It also depends on the climate and load environment you plan to run the truck. If you want to match stock capability, you'll need to move at least stock amount of air across the radiator. Less can be less, etc.......
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Clint is correct, the fan set ups on the coaches are a 4 fan configuration that covers the complete core. It will pull small children and animals into the radiator when they are fully on, did I mention they are variable speed?
On early trucks, with 5 to 7 blade fans, it was not uncommon to see a 15 tgo 25 hp loss when the fan engaged. New trucks/engines that have 9 to 11 blades can pull up to 50 hp right off the top when they engage. Cummins knows this and the later calibrations were trimmed so when the fan caame on, the fueling increased so the power would not fall off. You could hear it as soon as the fan came on, manifold pressure increased, turbo speed came up but the power didn't fall off.
I miss running the dyno....
On early trucks, with 5 to 7 blade fans, it was not uncommon to see a 15 tgo 25 hp loss when the fan engaged. New trucks/engines that have 9 to 11 blades can pull up to 50 hp right off the top when they engage. Cummins knows this and the later calibrations were trimmed so when the fan caame on, the fueling increased so the power would not fall off. You could hear it as soon as the fan came on, manifold pressure increased, turbo speed came up but the power didn't fall off.
I miss running the dyno....