Deere offers three engine air breather choices when buying a new machine. 1. Standard breather box with Rotary Ejector. 2. Heavy Duty breather box with Rotary Ejector. Which simply is a larger canister and filter element. 3. Either box can be also outfitted with the Snow Rotary Ejector Pre-Cleaner Kit. Our 672G machine came with #1, Standard box with Rotary Ejector. This places the Rotary Ejector about 10" above the hood. Here's a pic with the side door open which is how you access the filter element.
When talking with the Dealership Technician he said operators sometimes have problems with the airbox getting sucked full of snow. He contributed that to the late model Tier IV machines needing the hood to be higher to fit all the EPA stuff. Said this leaves the Rotary too close to the hood where it tends to gather snow dust. I didn't have any problems with it last Winter but we had a very mild snow year. Not once did I push snow in really cold weather pushing powder snow. So little snow flying around or gathering on the hood. Here's a pic of our previous D model pre Tier IV machine. You can see how much lower the hood is and how much larger the gap between the top of the hood and the Rotary.
So I purchased the parts to convert our system to the Snow Rotary version. It required a new intake box that bolts to the top of the hood. Also required a new intake tube that slips into the opening in the top of the box. Rotary Ejector then clamps to the top end of the tube. The tube is approximately 14" long and can be adjusted to whatever height you desire. Here's a pic of the original tube that was bolted to the hood.
Remove the original tube. Install the new elevated box using the same 4 bots that held the original plus two additional bolts that are already there on the hood. The nuts are welded to the underside of the hood. Swapping out the old tube and installing the new box took 3 minutes max. Then clamp the Rotary Ejector to the top of the tube insert. Drop the tube insert into the box tube and determine the height you want. Tighten the clamp. Another 3 minutes. I could have set the Rotary up another 5-6". But the overhead door of the shop we park in is only 12'. The top of the cab on the grader is 10'6". So I set it with the bottom of the Rotary about even with the top of the cab. Since I had never encountered problems previously I have no basis of comparison. Maybe an operator will read this that has encountered the problem of plugging the breather and can comment.
JD has a similar problem with there big 4wd tractors. They have the air intake at the corner of the cab. In really dusty conditions the dust swirls right around the inlet. this will plug the air filters in one afternoon. we extended the pipe up past the top of the cab, about a 2ft extension. it made a world of difference. I could see the snow swirling right behind the cab while plowing with the grader. I could see that it would fill up with snow in the right conditions.
With a turbine precleaner it's usually recommended that the turbine assembly should be installed well above the height of any surrounding panelwork, like the cab in the case of the grader. That often causes problems because the extension tube needed to get it that high requires struts or something similar to support the weight of the assembly. EDIT: In the case of the grader I'd say that extension tube still isn't set quite high enough for my liking, IMO it ought to be another 6-9" taller to get the bottom side of the turbine assembly right into clear air. What should be borne in mind is that the turbine sucks air in from underneath as shown by the arrow. So if snow is swirling around behind the cab it could possibly still get sucked into the precleaner.
I've ran JD graders for 31 years. I've never had one plug so bad I had to stop and clean it. I've opened the canister and found it 1/4 or 1/3 full of snow dust. Bear with me and I'll tell a funny/sad story about an operator near me. Him and I were visiting and he asked if I had problems with the breather filling with snow? I said what I just said above, not really. He said he has to carry an extra filter in the cab. After a couple hours the machine will start losing power and he has to swap out the filters. Putting the clogged one in the cab to thaw for reuse. He runs a very similar JD grader to the one I run. I was really stumped by this..... After a few minutes of question/answer discussion I said I don't think your Rotary Ejector is functioning. He looked at me with a complete blank look. I said do you know if the fan inside the Ejector is rotating? His look got even more blank if possible. Finally he mumbled what fan? So I described the workings of the Ejector and explained if the fan is seized and not turning freely the breather cannister will be sucked full of dust or snow. The purpose of the Ejector being to spin that material to the outside of the bowl and "eject" it out of the slots in the bowl. He said he didn't have any idea if it was turning or not. I asked how long he has had this problem? He said the past two Winters. Can you imagine carrying a spare filter element in the cab and swapping them every couple hours so it can melt all the snow out of it? Can you imagine how much moisture that would put in the cab? So,,,, I said do you have problems with your windows fogging over? He said no more than normal. I said what is normal? He said most of the windows fogged over with clear spots right where the various vents blow onto the glass. I said none of my windows fog over at all. Once the machine gets up to operating temperatures the heater keeps everything clear. The cab is warm enough for me to work in a T-shirt. He just laughed and said not in my machine you won't. So,,,, I said get the Ejector fixed so you don't have to carry a wet filter element with you and things should get better. After a minute or two of further conversation I said do you run the AC in the Winter? We went back to the blank stare look and he said why in the World would I do that???? So,,,, I explained how the JD controls are set up. There is a push button switch on the main switch panel that has a snow flake symbol with an indicator light when turned on. Yep, he knew what that was. I said I can't remember the last time I turned that off. Actually I think it was 20 years ago when our compressor quit and I turned it off to minimize damage. Otherwise it's on all the time. Adjust the temperature control knob and fan speed to create whatever climate you desire. Never turn off the AC button. Blank stare. So,,,, I explained how the AC being on will reduced moisture in the cab. And if I spend a long day in the cab I have to remember to drink a couple bottles of water during the day or I'll get dehydrated. So,,,, he then said maybe that's why my grader won't start after running a long day pushing snow? I asked the logical question, do you have a block heater and are you using it? He said, no not that. The start button won't activate the system and activate the starter. Hmmmmmm..... He said I have to pry the door open to get in because it'll be froze shut. Then I have to put an electric heater in the cab for an hour or so to thaw out the electronic switches so it will start the engine. So,,,, I said do the things we've discussed and see if you get along better next Winter. This conversation took place last Summer. I'm anxious to talk to him after this Winter and see how he gets along. If it's humanly possible I felt sorry for that machine. Can you imagine running a machine with those problems without searching for a solution?
And that bracing is accomplished with the box that's added. The box is stamped and welded out of 3/16" steel. Very strong to withstand the extra stress of the Ejector being that far above it. I agree in regards to the height Nige. And the tube is long enough to telescope it another 5-6". My problem as I described is I can't clear the doorway with it any higher. I left about 4" of clearance so if the concrete floor heaved in Winter or I have the chains on I won't hit the doorway.
I see where you're coming from with the restricted height of the door. Other than raise the building a foot or so.........
Or just deflate the tires every day before you park the grader....
Jeez. I cant imagine the humidity in that poor thing. Think of the electronics .
The work day must feel twice as long trying to peer through the holes made by the vents in the fog. And that must be loads of fun at night.
Someone down the road will buy that grader and have the weirdest electronic problems in the cab......
I've not looked in the cab of that grader. But I expect it's in pretty bad shape. It's 7 or 8 years old. Last 2 or 3 with the moisture problem. I'm fortunate to have new machines. Usually around 1,500hrs when we trade. I'm picky about the inside of the cab. After all, I live in there. No smoking. No spitting on the floor. No running with doors/windows open. Air tight filtration system. When we trade our machines the inside of the cab looks brand new still having that new smell.
I’ve never had any trouble with precleaner and filters plugging up with snow I do notice that cat has there precleaner behind the exhaust stack further away from the cab be interesting to see if I have trouble with my new Deere.I’m also surprised he didn’t know to run with ac on to keep moisture out I prefer to wear long sleeve t shirt or sweatshirt in cab I like it cool so snow don’t stick to the windows.
I run the fan on low, moderate the temp with the heat control. If it's really cold outside I shut all the vents pointing at the glass. Just crack one open on each side of me pointed at me. Keeps me comfortable. Keeps the glass cold so nothing melts and sticks to it. There's a "defrost" switch on your right by the heater controls. This opens/shuts the vents on the front glass. I usually have that closed so the windshield stays colder. Once in awhile things will be just wrong and I'll open it to keep the windshield wiper area from freezing if I need to use it. My feet never get cold so I keep the floor vents by them closed. I'm at 650 hrs. Will put on a new set of cutters in a couple weeks so I have fresh ones to push snow. I've rotated these several times and am still on the original pair.
Must be different where it gets "really" cold. In the wet heavy blizzards we get here I found the best way to keep the windshield clear was to run the windshield defroster on full fan, full heat, wipers on full and modulate the temperature with how far you open the windows. All snow here is sticky as peanut butter and must be kept at bay with extreme amounts of heat.
I don't have any windows that open. I never run my heater on high for more than a very few minutes until warm up. Our snow varies. What you describe I hate because that means the roadbed isn't frozen. We'll get that at least once a Winter. Run vents pointing at glass to keep from fogging. Heat range in the low 1/3. Fan on low. Other end is dry, light powder and temps around zero F. Close vents to glass. Heat range in the middle at most. Fan on low.