I got my D31 back from an engine rebuild a few months ago and just noticed the fan is blowing the air out the front of the machine. It doesn't make sense to me that you would want to blow hot engine air across the radiator and I'm pretty sure it wasn't doing that before. I haven't looked yet to see if it is an electric motor that is hooked up bacwards or if the fan was put on backwards. Either one would not surprise given what I now know about the "highly recommended" guy that did the rebuild. Has anyone else ever seen this?
Does it have a flexaire type fan? Also some fans can be manually reversed.
Most dozers and track loaders that I've been around use pusher fans, some have reversible fans.
Yes. I checked and it appears to be installed correctly and is fan belt driven. I guess that is to keep the radiator fins from clogging up with dirt. Thanks for the feedback
Unless you're working in landfill you need a pusher fan.
We used them reversed in the winter, used in combo with tarps they were surprisingly warm, open machines of course, first few hard bumps running on frost would shake the trapped dust loose and the fan would drive it back in your face. Life is much nicer now that cabs have become more common. Nige, would think paper coming over the blade would suck on to the grill in a land fill, never worked in one, thank God, (weak stomache)
Why would you not use a pusher fan in a landfill?
Actually in a landfill setup it's common to use an automatically reversible fan setup. The ventilation of the engine compartment in something like a dozer, as many have pointed out, is a "pusher" type. It pulls fresh air from the spaces around the belly guards & transmission, carries it over the engine, and then pushes it past the radiator out towards the back of the dozer blade. The most common material moving past the fan and the radiator is dust. That's why the engine is always dusty. However in a landfill application the material that's flying around is generally paper, and you don't want that getting into the engine compartment and causing a fire hazard. It's normal to have the bottom of the tractor sealed tighter than a duck's ass to avoid trash getting in and stinking the machine out, so there is almost no path for air to get into the engine compartment as there would be on a conventional tractor. Therefore the fan has to suck for most of the time. I'm not 100% sure on the control side but every so often the fan blades are moved hydraulically from "suck" to "push" to blow all the accumulated paper away from the front radiator guard, then they move back to "suck" mode again. On a landfill tractor everything is designed to keep paper & other flammable materials out. Even the cooling air flow to the alternator is ducted. I've seen some tractors where the alternator is actually supplied with air from the air filter.
Agreed, every thing we buy for our landfill has an automatic reversible fan. Helps keep the mechanic's away.