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850 J cooling fan air flow direction?

JCP6.8

Member
Joined
Feb 24, 2013
Messages
5
Location
McMinnville Tennessee
We have an 850j, Replaced fan motor and fan last fall. Motor seal was leaking and the ends of the fan were broken off. Didn't notice anything last fall, wasn't ran much through the winter. When the weather got hot this summer the cab sheet metal would get too hot to touch inside the cab with the air on. Temp gun would read 130 on a good day. The fan turns clockwise drawing air into the engine compartment after the parts were changed. Before it normally blew from the engine compartment out to the blade, except when the auto reversing fan would come on blowing debris off the hood. Does just the opposite now. Deere tech has checked the machine and says its "normal". We have had the machine for several years and was fine before the Motor and fan were replaced.

The fan motor has three lines, all different sizes so the lines can't be swapped. Tried turning the fan around, sticker on the fan says radiator side, and the blades would still draw air the same direction anyway. My Deere parts rep says he doesn't know of any one with a J, we can't be the only ones in middle Tennessee with a J.

So, which direction does the air flow on your J? Can you warm your dinner up on sheet metal inside the cab with the air on?
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,891
Location
WI
The first thing I'd do is get your part numbers off the invoice, and your serial number and go to jdparts.com and double check that everything is correct for your serial number.

Fans are designed to pull the air from the convex side of the blade and push it out the concave side of the blade, that will tell you how it's supposed to be running.
 

JCP6.8

Member
Joined
Feb 24, 2013
Messages
5
Location
McMinnville Tennessee
Thanks Delmer, Didn't know about jdparts. Have an account now. Have given the parts guy at Deere the numbers directly off of the fan and motor, I think the tech checked also. I'll recheck through jdparts again. Was hoping that there would be a fan pitched the opposite direction. The old parts have already been discarded.
 

kjkoch

Active Member
Joined
Dec 13, 2012
Messages
41
Location
Texas
It should blow your hat off if standing in front of the radiator. Looking at the parts book picture, it looks to me like the one shown should run counter clockwise, but those pictures aren't always accurate.
 

mestizo

Well-Known Member
Joined
Jun 24, 2008
Messages
109
Location
USA
If your fan is running backwards, its not cooling enough. Fans arent designed to run opposite direction all the time - you give up some cooling efficiency, but purge out the coolers. Thats why the fan reversal cycle time is limited.

Assuming you got all the right parts, you might have a line crossed somewhere between the pump and motor. The reversing valve is inside the front left engine door, but these lines should have different sized fittings to prevent crossing them up.

Whats your SN?
 
Last edited:

JCP6.8

Member
Joined
Feb 24, 2013
Messages
5
Location
McMinnville Tennessee
SN is 137835. There are three lines on the motor, all different sizes, can't be mixed up. New fan number at316508, motor number at304104. kj normally it would before the parts swap. Deere tech is saying it should be pulling the air into the engine compartment. We have 8n's 9L's and one 9n, 650h and a couple of trac loaders they all blow from the engine compartment to the blade. Deere is telling me the J's and K models both blow from the blade into the engine compartment. I was hoping someone that has a j or k could tell me which way their's blows. No machines that model in our area that I can look at. I ran it yesterday clearing, the leaves were getting sucked into the radiator screen in front, reversing fan would come on and clear away some of the debris. Air flow is backwards to what it was before the parts swap. Talked to Deere today they still have a case open on the machine trying to figure it out.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,426
Location
G..G..G..Granville.........!! Fetch your cloth.
Does the fan motor have a direction of rotation indicated on it..? 2nd is a big if - do you still have the old fan motor..?
With direction of rotation arrows you could compare the old motor to the new one to see if they both rotate in the same direction.

I have no idea in what direction the fan is supposed to blow on your machine but every dozer I've ever come across blew the air out of the radiator towards the blade so that dust & debris got blown away from the tractor instead of being pulled towards it. On that basis if your air flow is in the opposite direction it would be very strange.
 

mestizo

Well-Known Member
Joined
Jun 24, 2008
Messages
109
Location
USA
Fan should be blowing out during normal operation. You've got the right fan and fan motor. JDParts calls out AT372688 for the motor, but its a substitute for AT304104, so same part.

Make sure your lines match this diagram from the pump to reversing valve to motor.

USpV76y.jpg
 
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kjkoch

Active Member
Joined
Dec 13, 2012
Messages
41
Location
Texas
The 750J that I worked on last week blows out the front and runs counter clock wise. Maybe that motor was in the wrong box, it should have a tag on it so you can compare the part number to the one on your invoice. I have seen more than one pump or motor put together backwards too, I've done it myself.
 

JCP6.8

Member
Joined
Feb 24, 2013
Messages
5
Location
McMinnville Tennessee
Nige, no direction of rotation on the pump and the old parts are already gone for scrap. Sure wished we had them back. Mestizo, I'll try to print that off and check flow direction Monday, the only lines that were removed were on the motor. Standing in front of the machine the fan is turning clockwise, I'm with you kj, I'm thinking something is backwards in the fan motor. Thanks for all the suggestions fellas, Ran it today until it got to throwing a high fuel temperature code.
 

still learn'n

Senior Member
Joined
Feb 6, 2012
Messages
455
Location
Kansas
We have an 850J serial # 153368 and im quite positive the air from fan goes toward blade because we have had several hoses blow on the machine and didn't clean the oil out of belly pan and the oil got sucked thru the radiaters also all the junk that was plugging up the radiater was on the engine side so it would have to pull air from engine side.
 

fpgm04

Well-Known Member
Joined
Dec 31, 2009
Messages
214
Location
USA
I don’t have an electrical schematic for this machine, but could it be as simple as the proportional solenoid and the reverse solenoid have been cross connected? Ie swap the electrical harness connections on the solenoids at the valve.

Referencing solenoid connections shown on Mestizo’s diagram (44-Reverse solenoid and 46-proportional solenoid), if the wiring is long enough, it should be simple enough to flip the solenoid connections and give it a try.
 

JCP6.8

Member
Joined
Feb 24, 2013
Messages
5
Location
McMinnville Tennessee
Talked to the service guy at Deere again Thursday, They finally agree that the fan is running the wrong direction. Got to work on it again Friday, Took Mestizo's schematic and took the top and bottom lines off. Turned the engine over and the fluid is flowing the right direction. Called service back, he wanted the complete s/n and p/n off of the fan motor again. Called him back before quitting time, he said p/n crosses over to a different number now, which I think we have already discussed on here. Got the new one ordered be here Tuesday. Hoping they might help some with the cost sense the last one wasn't the right one. Thank for the help Guys.
 
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