John Deere 4300 With 430 Loader , loader very slow and non responsive

Joeblack101 · Oct 10, 2017

So I wanted to come back with my findings . In the book the quick disconnects are labeled A B C D from left to right if sitting on the tractor . I knew B was working for bucket in so I started there . Plugged in the test gauge and I had 1800 psi , I adjusted relief valve and got pressure to spec at 2500 psi . So I know the pumps ok . I went to port A for bucket out , I had 1500 psi ( I'm guessing it don't need as much for bucket down and loader down . Went to port C , Loader up ( 1000 psi ) ... and A loader down (1500 psi )

A: bucket out : 1500 psi
B: bucket in : 2500 psi
C: loader up : 1000 psi
D: loader down : 1500 psi ..

So I looked real close at the linkage on the valve and it's almost like it's stuck from moving any further . Like something is binding in that valve block assembly . I looked real close with a bright light, and you can see it is half shiny further back the valve like it used to travel that far . So I can't get a parts breakdown for the valve assembly any more . Only a whole knew valve which is 997$

... so I guess my next step will be tear the valve or spool out and see what's going on

oldnslo · Oct 10, 2017

On the end opposite the linkage there should be a cover over the end of the valve spools. Carefully remove this cover. There should be a spring or springs held in place via some method. Could be retaining ring or bolts. Confirm nothing is out of position or binding in this area.

On the lift lower spool there will also be the detent feature for float. I am not sure how this is assembled on your valve so be very careful since there could be some spring loaded pieces under this cover.

Pressure should be similar for all functions.

Dutch445 · Oct 11, 2017

I wouldn't rule out having some of the hoses in the wrong place,
if you have crossed circuits thru all of this nothing will act right and be very hard
to diagnose.
switching circuits to test them was a good idea, but, are you 100% sure that you have
the right circuits matched together going to the same valve?
(might take a little detective work, following hoses up to the loader, and then make
sure you have the same circuit at the quick disconnects from the valve)
i know a lot of the color coded dust caps have been lost by not on tractors this age,

Joeblack101 · Oct 13, 2017

Sorry if there was confusion in my posts . Loader was used to clear some ground for a patio and then started acting up . Yes it was a low on fluid and I only put 40 hours on this since purchasing it . Because I never serviced it and had no clue when someone did , I drained fluid , cleaned the suction screen . There wasn't much in the screen . At least I expected it to be more honestly . The backing plate was very brittle but I could not find any of the other pieces in the manifold . So idk where they went . But I kinda ruled out the quick disconnects by replacing male and females . And the pressures just aren't right . No I wanted to triple check myself with the connections bc I know how easily they can be screwed up after swapping . These had the color caps still clearly visible so I have the colors matched from where they were when it probably worked correctly . Weather has been crappy here past few days . I'd like to tear the back cover of the valve assembly off this weekend to see what I can find with it . I can see it barely moves the spool in the loader up and down valve . And feels like it's jamming . So I will post what I find to possibly help someone else if they have this problem . Thankyou again for all the help on here . I very much appreciate it

oldnslo · Oct 13, 2017

Joe,
If the spool barely moves I would definitely suspect that something in / under the end covers is the problem. People have found them full of water, rust, mud, etc. I certainly hope it is as simple as good cleaning with no expensive unobtanium parts required.

Joeblack101 · Oct 28, 2017

So I know it's been a few weeks but I finally figured it out . I'm attaching images . I removed the PTO linkage that connectors to tractor ( what a pain , ) then got the cover off the rear. I suspected to find a broken spring or something , but nope . All had plenty of lube and looked ok. I removed the spring on the valve giving me issues and I could get the D tent ' cup ' to engage and disengage by hand . And functioning ok . But the valve was so stuck it wouldnt come out more then 1 inch. I broke some rules and got out a punch and hammer . I had to use the hammer to force it out . It was in there to the point I had to hit pretty hard . Finally broke it free . A bunch of Oily crap fell out the back and I couldn't tell exactly what it was bc it fell on the dirty transmission . I seen virtually no scaring on the spool valve once removed . So I checked inner and outer O rings and found no issues . So I just cleaned the valve and everything else the best I could . It went in easier , still a little tight . But I reassembled and thought , screw it . I'll try ... and low and behold it works like new !!! Still a little bit tighter then I would like but it's working flawlessly and goes into d tent just fine now . All loader functions are perfect . Something was blocking it from full movement . I'm just happy the 900$ valve assembly didn't need to get ordered . So now I'm back in business . Thanks for the help and replys on this . I know in the future I might need to replace the whole assembly since I can't get individual parts anymore , but for now it works great