John Deere JD400 service manual

Wacka100 · Nov 7, 2015

I have a John Deere JD400 loader backhoe with hydraulic issues could any one help me out with a copy of a workshop manual to help to try:shocked:and start sorting out the problem.

Tx Jim · Nov 7, 2015

:welcome: to TBN
I can't help with TM but 1st thing you need to do to tractor if you haven't already done so is change hyd filters & check/clean sump screen(parts key 15). There will be a fitting with a hose holding screen in trans case not shown in parts photo. What is tractor not doing?

Wacka100 · Nov 8, 2015

Hi jim tractor will only lift the bucket when machine is moving forward but will not allow backhoe to operate

Jet A · Dec 15, 2015

I don't know if this will help or not.
Make sure clutch is released when using the hydraulics. There is a feed pump in the tranny that provides fluid to the fwd engine driven pump. Also my manual states to have the reverser in FWD if using the backhoe.
Have you tried cleaning your filters and screens and perhaps replacing your hydraulic fluid?

Alex

Tx Jim · Dec 16, 2015

Wacka100 said:
Hi jim tractor will only lift the bucket when machine is moving forward but will not allow backhoe to operate

Did check trans screen? You could also check trans filter relief valve that shown in photo to be sure it's not stuck open? Get gauge and check stand-by pressure which should be 2250 psi

buickanddeere · Dec 16, 2015

Why not call 1-800-522-7448 for the real JD manuals ? The parts book is free online at the JD web site.
Countless front pumps have been changed by guessers when the actual problem was a lack of oil being pumped up to it's inlet port.
A leaking closed Center hydraulic valve, a leaking/stuck relief relief valve or if somebody has added an open Center hydraulic valve will cause problems.

Tx Jim · Dec 16, 2015

Jet A said:
Make sure clutch is released when using the hydraulics. T
Alex

Alex
I thought that on units with a reverser that the trans pump was driven from pressure plate not traction clutch shaft so whether traction clutch is engaged or not is mute. Granted my knowledge of ind tractors is limited as I was employed by an "AG only JD dealership".
Jim

Jet A · Dec 17, 2015

Jim,
I'm new to the JD400. I got mine a month ago and do have the parts, service and operator manuals.

The operator manual states,
"The transmission oil pump supplies oil for the main hydraulic pump. Therefore, avoid prolonged disengagement of the engine or PTO clutch which controls Oil pump operation. Disengaging the clutch for long periods reduces supply of pressure oil for hydraulic functions."

It is not specific to the installation of the reverser.

again, I just got mine and I'm sure you've had more experience than me, it's just something I found in the manual.

Alex

skot0123 · Feb 26, 2016

New JD400 owner trying to chase down hydraulic problems and springing new leaks as I fix old problems. Is there a trick to getting the screen out? I have pulled the 1 1/4 bolt/plug and see the end of the screen but can't get it out. I've tried snap ring pliers, screwdrivers, a dowel but can't get it to budge. I don't see a plug on the other side that I could remove and push but maybe I'm wrong.

Tx Jim · Feb 27, 2016

Welcome to TBN
It sounds as if the sump screen is crumpled. One has to get tough when the screen is crumpled or badly coated with sludge.

Jet A · Feb 27, 2016

Try bending some coat hanger wire or something similar to catch a piece of that screen and pull it out.

Alex

skot0123 · Feb 27, 2016

Jet A said:
Try bending some coat hanger wire or something similar to catch a piece of that screen and pull it out.

Alex

Well, I may have screwed the pooch in this one. It's what I get for trying to work on hydraulics and knowing nothing about it. The plug I took out to get to the screen wasn't for the screen. I finally got what I thought was the screen out and it ended up being a valve. The best way to describe what came out was it was like a large version of a forward/reverse piston in an air impact gun. I put it back in but it had a key way or notches about mid way through and I'm not sure if I messed up whatever went in there. I THOUGHT I was going for sort of a cartridge screen type thing but stopped and thought about it and realized it was simply a tube screen and that it was right there where the house goes in. It is out and cleaned now but I think that may be useless now. The plug and valve I mistakenly took out is almost directly above the vertically mounted filter cartridge and is about 6" long. Any help or advice would be greatly appreciated!

Tx Jim · Feb 28, 2016

Are you referring to valve(parts key 3)? That's the hyd filter relief valve. If so it needed to be removed also especially if it was stuck open.

skot0123 · Feb 28, 2016

Tx Jim said:
Are you referring to valve(parts key 3)? That's the hyd filter relief valve. If so it needed to be removed also especially if it was stuck open.

Yes, I hadn't been back on the computer, only my phone, so I couldn't see the picture. It was the relief valve

skot0123 · Feb 28, 2016

Only the valve part came out nothing behind it. Thanks for the reply, I don't feel as bad now about possibly ruining the transmission

Jet A · Feb 28, 2016

I would strongly suggest buying the service manual from John Deere. If you go online you can download it instantly in PDF format, or order in on CD, or order a paper manual.

skot0123 · Feb 29, 2016

Thanks for the help. I got it all back together and found the sectionals on JDparts. I'll order a manual later this week. Still have the same problem I had before I started. Blew another O ring out. Once I get the manual I'll try to tackle it again. Hard to even describe problem I'm having when I don't know the name of the part having the problem,lol