John Deere 4020 RSCV hydraulic Rear selective Control Valve adjustments - zeketheantiquefreak

[@wespeters9667]

Absolutely awesome tip! Now my bucket works great after adjusting

[@rafaelacostaalonso2848]

Exelent video ...saludos desde chihuahua Mexico

[@zeketheantiquefreak8518]

Thank you. Hope you and yours are well.

[@MY-bw2nb]

Yes i realize that it's 4 year video but i have a question about plumbing in a second closed center spool valve to run the loader Deere service told me to tee off of my pressure line that goes to spool valve and return teed off to the return line down on left side by pressure relief valve. You showed the plug on bottom of priority valve is that the same cavity that pressure line comes from for spool valve if this is the case straight down from the priority valve on the casting where the console attaches there is a orb threaded port that goes into the casting and does a 90 out the side of the casting by brake pedal so if that plug is same cavity makes easier to install the pressure line for second valve however is there any better place to run return line too because that 45 fitting at pressure relief wont come out unless you remove pressure relief valve first i could use rubber hoses to deal with it but the steel lines are pristine . Service told me not to just dump return line to case because you will starve pump for oil and lose the pressure relief function that's why I was asking about a better return line option if you know of one . Now I know how to speed up my hydraulic flow thanks. I have 3 66 4020s they all have steel lines from spool valve down through the console with joiners then carrying on under floor pan back to scv couplers.

[@zeketheantiquefreak8518]

Thank you for the comment. I will check into this and get back to you, probably within a day, if that is ok.

[@zeketheantiquefreak8518]

Ok... I am not sure I can be of help on the return. I haven't had the need to put a loader control valve on the right hand side, so I have no experience with the actual application/process. I was told by a fellow that is very familiar with the 4020's that you could return back to the filter housing... That said, maybe the later models have a 'plug' in the filter housing cover. Mine does not. Maybe tomorrow I will lay under the tractor and see what is there. I can see a bung to the rear of the filter housing, but that may be the pressure release valve or the filter screen... Sorry I could not be of more help for now.

[@ihd-3603]

You’ll want to get a filter housing with the port in it to return directly to the filter to help prevent cavitation of the high pressure pump. Oops. Just realized I responded to a video from 3yrs ago. 🤦‍♂️

[@wwreakin3085]

I just replaced that main line from the frount pump that’s behind the fuel tank and runs back to the counsel! Does the system need bleeding because the steering is hard, brakes are soft and three point jerks when raised! Fluid is full! JD 4000 diesel late model!

[@zeketheantiquefreak8518]

Sorry for the tardy reply... Not all of the comment came through at first. If you haven't solved it by now I can ask around. It is a somewhat different tractor than my early 4020 so my manual may or may not be of help. If you just had the pressure line off the pump shouldn't have lost fluid on the suction side, no? It may be as simple as cycling all of the hydraulic systems to force the air out of the system, but I would not want to advise you to run a dry or cavitating pump.

[@wwreakin3085]

zeketheantiquefreak I was told there may be an issue in the steering pump with dirt/contaminates that may of messed a valve up! That why it only steers to the left and hard to no steering to the right after bleeding the pump! Can this be true?

[@zeketheantiquefreak8518]

Yes, I feel that dirt in the steering valve could cause these problems. I suggest getting onto a John Deere Q&A forum and describe the problem in as much detail as possible. Very knowledgeable people read these forums and may have an answer for you. Please keep me informed.

[@zeketheantiquefreak8518]

A couple of months has passed... Were you able to solve the problem?

[@wwreakin3085]

Yes, bleed bleeder on top of power steering pump! There was an air lock somewhere in the line! Full steering now... thanks

[@Watchyn_Yarwood]

Got 2 4020s, 1968 & 1970. The '68 is really leaking at the SCVs mounted at the rear. Curious if you have done a reseal on one of these model 4020 SCV? The prices on rebuilds are astronomical! I really enjoyed the SyncroRange shifter re-bushing you did. It's next on my list of things to do on my 1970 then the leaking SCV.

[@zeketheantiquefreak8518]

Fortunately I have not had any problems with the rear SCV's on my '64. I am assuming that your problem is more than just the o-ring where the hose coupler seats against. Are they the right couplers? To see an exploded view of your units go to jdparts.deere.com A real useful tool is forums.yesterdaystractors.com Thank you for the comment and let us know what you find out. There is a video here on You-Tube posted by Abilene Machine, Inc: 'Rebuilt selective control valve'. I haven't watched it myself but may have info you need.

[@zeketheantiquefreak8518]

A month or so has passed... How did you make out with the leaks?

[@harisonk]

The covers say 4020, but the handles on the sides of the dash are indicative of a 4010. Did the very early 4020s come with 4010 dash handles?

[@zeketheantiquefreak8518]

Yes, you are 'bang-on'. Being the first year (1964) this unit would have to wait a year for the diff lock for instance. An interesting article on the differences between a 4010 and a 4020 can be found here: www.greenmagazine.com/articles.asp?id=17 Thank you for your comment.

[@harisonk]

I came back to this video to re-remember which holes are used for the float position and I noticed the hoses coming off the side of the lower SCV unit under the hood. Are those a Deere thing or were they originally steel tubes? I'm wondering as someday I want to add a second SCV to our 3020 and kinda want to keep it how it would have looked brand new.

[@zeketheantiquefreak8518]

@@harisonk Oops, I only found this comment now. My apology. As far as I know this arrangement is original. A peek at a parts diagram may reveal the truth.

[@betovillarreal8908]

I have no pressure on hydraulic oil is the pump shot or is it by passing

[@zeketheantiquefreak8518]

You might want to try one of those 'forums' that are peculiar to your make and then describe the problem. I have found these forums useful in the past. Thank you for the comment.

[@DaddioTeale]

How about something on rear 3-pt control cables repalcement and caligration :o)

[@zeketheantiquefreak8518]

Thank you for the comment. Unfortunately this 4020 doesn't have a three point on it so I am afraid my limited knowledge of that system would show. Can you get access to a suitable service manual?

[@danymd504]

ok