John Deere 4200 loader slow

[DiskDoctr]

Dan,

Be sure to recheck your hydraulic fluid level. What kind of fluid did you use?

You did recheck it after starting and working all the cylinders, right?

It's the easiest thing to check

- JC

 

[Dmatt1222]

:thumbsup:My problem is solved (for now)

I rechecked the suction lines and all were in good shape with no problems found. I started tractor still no action from loader.

I checked the pressure using a setup described by KENNYD ( gauge found at harbor freight 12 bucks, hose with male QD from my log splitter and 1/2 too 1/4 bushing from hardware store) max pressure at all QDs approx 105 psi.

I then pulled off the R fender to inspect SCV. All linkage connected and properly adjusted.

I removed the only relief valve I could find. A non adjustable relief threaded into the SCV. I found no junk in the valve but I operated the valve by forcing open the relief piston with a 3/16" pin punch followed by a solvent cleaning.

After reinstalling the relief valve I rechecked the system pressure and found it to be 2050 psi. I reconnected the loader QDs and the loader worked like brand new!

I would like to thank everyone for your help in solving this mystery and saving me $$$$ I hope this thread will be of help to others with simular symptoms.

Dan

 

[arrabil]

Awesome.

 

[kennyd]

Great news Dan:thumbsup: There should be a adjustable PRV on the tranny somewhere also I think...Perhaps this would be a good time to invest in the service manual on CD?

 

[DiskDoctr]

Whoo-hooo!!!!:dance1::cool2::thumbsup:

 

[beenthere]

I'd like to pinpoint that relief valve on the schematics. Anyone with pics or more specific id of where it is located? I have the CD service manual (4200, 4300, 4400) and a page or figure id would be a big help.
Thanks, and great to hear that the problem has been fixed. Special thanks to kennyd here too.

 

[mjncad]

Kenny is the man when it comes to hydraulics!

Glad you got it working for low $$$$.

 

[Egon]

[Great news Dan:thumbsup: There should be a adjustable PRV on the tranny somewhere also I think...Perhaps this would be a good time to invest in the service manual on CD?/QUOTE]

There are two PRV's on the transmission. Neither are adjustable. The manual calls for a 10,000 psi gage for these.

They are located just to the right of the HST filter when facing forward's. There are also plug locations for attaching a gage.

 

[beenthere]

I poked around in the CD for this Deere, and found there is an adjustable valve on the SCV block (am thinking this is the one the OP found to be sticking) and have two pics showing it here. A third pic shows the placement of the two Forward/Reverse valves mentioned by Egon that are only for the tranny, not the hydraulics as being discussed (just for clarity here )

 

[kennyd]

I poked around in the CD for this Deere, and found there is an adjustable valve on the SCV block (am thinking this is the one the OP found to be sticking) and have two pics showing it here. A third pic shows the placement of the two Forward/Reverse valves mentioned by Egon that are only for the tranny, not the hydraulics as being discussed (just for clarity here )

Thanks BT, I knew there had to one that was adjustable somewhere!

 

[J_J]

Dmatt1222,

Just curious where you put the gage to read 105 psi. Did you plug it into the lift or curl circuit QD, and activate the lever. If the relief valve in the FEL was relieving the fluid, it should have been hot to the touch. Did the 3pt work before you cleaned the valve?

 

[Egon]

Beenthere, I was trying to post the pictures of the transmission PRV's but due to being challenged I could not get them into the proper format let alone find some of them after scanning!:ashamed:

 

[Dmatt1222]

Just to clearify things I used a 0-3000 gauge and my readings were taken at the lift and curl quick disconnect fittings.

The pressure I found at these fittings was 105 psi ( the gauge needle was slightly over the 100 mark) while the control lever was accuated and dropped to 0 psi when the lever was in its neutral position.

The relief valve I played with is threaded into the loader control valve body and looks like the one in the picture that Super member Beenthere posted with the exception that the one I found is is non-adjustable.

I did not run the tractor with the the fender remove to gain access the the control valve so I don't no if it was generating any heat, although it makes since that it was.

After accuating, cleaning and reinstalling the relief valve my pressure at these fittings was 2050 PSI

Yes the 3 point hitch did operate properly thru out all of my testing.

Once again, I thank you guys for your help!

Dan

 

[J_J]

Just some casual observations. The gage should have been in the pressure hose from the pump. Even if the relief valve was stuck fully open, the gage should have read relief pressure when the levers were actuated. The 3 pt with no load only takes about 100 to 200 psi to operate. In order to build up pressure, there should be something in the fluid path to offer resistance.

 

[beenthere]

Beenthere, I was trying to post the pictures of the transmission PRV's but due to being challenged I could not get them into the proper format let alone find some of them after scanning!:ashamed:

Egon
The way I capture pics (anything on the monitor screen for that matter) is hit Print Screen. Then paste (Ctrl-V) into "Paint". Once in Paint, box around just the area I want, and copy (Ctrl-C). Go to File, and "new" for a fresh screen, do a paste again (Ctrl-V). Then can "save-as" to a .jpg file for posting here. Or can set up the print option to make a hard copy.

 

[Egon]

Thanks Beenthere

 

[DiskDoctr]

Egon
The way I capture pics (anything on the monitor screen for that matter) is hit Print Screen. Then paste (Ctrl-V) into "Paint". Once in Paint, box around just the area I want, and copy (Ctrl-C). Go to File, and "new" for a fresh screen, do a paste again (Ctrl-V). Then can "save-as" to a .jpg file for posting here. Or can set up the print option to make a hard copy.

If you're using FireFox, an addon call "FireShot" (free version) works well for any internet content. I turn on the 'capture entire page' option (not sure exact wording).

If using Vista, the "Snipping Tool" under Programs, Accessories works well. I added it to my Quick Launch bar so it is easily accessible.

I also use DoPDF in vista for making PDFs from any printable item. It is basically setup as a printer, but prompts you for the name of a pdf when printing.

- JC

 

[Egon]

Thank you JC.:thumbsup:

 

[mjncad]

If you have newer versions of Paint Shop Pro (e.g. 11, 12, 13), the program has a built in screen capture tool. That's what I use.

 

[Egon]

Thanks for the information.


I have photo shop of which I can only manage a few functions.

The scanner is an HPJ5750 and it has a tendency to send the scans to unknown places or in unobtainable form?