John Deere 6400 Hydraulic Fluid overheating!

[mastercraftka]

Hey guys!

Family bought a used 6400 couple of months ago has about 5600 hours on it has the 620 loader I believe.


Father in law was doing some road work and was on it for about 2 hours and got a stop engine light which showed to be the hydraulic fluid over heating. We changed all the filters and fluid and I was plowing one day and after about 2 hours got the same light. Everything seems to work fine. One other thing that happened in between was one of the remote couplers failed and we lost lots of fluid replaced it and seems to be ok now. The overheating although was before the remote issue.

Any clues to what is going on? Do they not put hydraulic coolers on these tractors? I grew up on a farm but have been away from these things for awhile until now. Hope we didn't get a dud!!

Thanks for the help in advance.

Mike

 

[Zebrafive]

JDparts shows an oil cooler. Also shows screens (but one version of the oil cooler P/N AL78246 serial number 113501 and less, says screens can be used with it) There are several P/Ns for oil coolers. It and/or screens may need cleaning.

 

[mastercraftka]

Yes I have seen those screens and I did clean them. I really didn't look at the radiator closely but I guess if it has one it is integrated? My father in law said it didn't have one just trusted him, I need to look further. I know we changed two filters and the screen that is in the rearend of the tractor.

 

[Zebrafive]

Radiator is separate.

 

[RPW]

Really get into those coolers. I thought I had everything cleaned on my 5520 but I was still having issues so I separated the coolers and found dirt was caked up in between and in the cooler fins.

 

[Industrial Toys]

I have a 6200 and never had any issues. I know from my Kubota Wheel Loader that the cleanliness of the cooler makes a huge difference. Blowing out is good. Carefully pressure washing is better.

 

[mastercraftka]

Cooler coils were filthy got them all cleaned keeping an eye out to see if there a small leak. We have the disc harrow down right now so I haven't had a chance to use it more than about 30 minutes or so. I am hoping it was the issue because it was really bad right behind the battery.

 

[dapeake]

Possible unfamiliarity issue?? The manual for my tractor has a fluid warm up procedure that if engaged and then inadvertently forgotten will overheat the fluid.

My 650 has a valve that when closed is intended to lock the 3pt cylinder in a fixed position by trapping fluid in the cylinder; when closed while lifting the 3pt control lever, fluid is forced through the relief bypass, which is set to a very high relief pressure, thus rapidly heating the fluid on its way to the sump.

Obviously this status would prevent 3pt operation, but my point is if optimal operation of your tractor requires fluid properties only attainable at temperature, your user manual, like mine probably shows a standard procedure (or device) to accelerate the warm up. That may be worth becoming familiar with, and since you are a new owner, may be the unknown and super simple source of the problem.

Dan
Campbell, CA

 

[mastercraftka]

I will look this up but if I understand what you are saying if this valve is closed the 3 pt hitch would not work:? If so that is not happening because the 3 pt hitch is working.

 

[mastercraftka]

So my father in law plowed for about 3.5 hours in the 100 degree Texas heat this weekend and finally got a high pressure overheating light again. This is after we cleaned the coils it definitely would have come on sooner before. We checked the coils for transmission leaks again and when we opened the cowling noticed that the battery had slide all the way up against the screens and the coil. We are going to secure the battery so it doesn't slide. Not saying it is the issue but definitely is not helping.