JD 200 series scv troubles.

[milkloss]

I think we may have been here before at the other place!

On our JD6920 we have one scv which has a seized flow control and one with a knackered mode control knob. We have our PA93 hedger on the tractor with the tractor providing hydraulics for the arm and last year there was a bit of a leak from the oil cooler. This has been put down to the spool lever being held in place using the black plastic lock rather than the detent on the scv unit itself. I'm not sure how but that was the gist I got and in any case it doesn't leak when driving dung spreader floor when I hold the lever full bore.

Long and the short is how do I fix the detent not working, as in hold itself in pump for the hedger? Had a look in there and the four balls are rusty and the pin/needle (with a sliding spring loaded conical collar on it) that these act on was seized. All loosened up and admittedly a little rough but still no detent.

Help. I am not so sure it is just scratchy balls causing me trouble

 

[Blue.]

I think we may have been here before at the other place!

On our JD6920 we have one scv which has a seized flow control and one with a knackered mode control knob. We have our PA93 hedger on the tractor with the tractor providing hydraulics for the arm and last year there was a bit of a leak from the oil cooler. This has been put down to the spool lever being held in place using the black plastic lock rather than the detent on the scv unit itself. I'm not sure how but that was the gist I got and in any case it doesn't leak when driving dung spreader floor when I hold the lever full bore.

Long and the short is how do I fix the detent not working, as in hold itself in pump for the hedger? Had a look in there and the four balls are rusty and the pin/needle (with a sliding spring loaded conical collar on it) that these act on was seized. All loosened up and admittedly a little rough but still no detent.

Help. I am not so sure it is just scratchy balls causing me trouble

@NZ Tech

 

[NZ Tech]

You buy a detent repair kit. The balls will be seized in the spool valve. Also at that stage the cable might be stretched and or oil in the cable so you wont be able to get float?.

You can clean the balls up and gt rid of corrosion.

Remove the cap screws holding down the black adjuster cap.. lift the cap carefully and then you'll see the detent balls. Remove the small cap and lift the spring and ball holder up at the same time... this will expose the balls. Dont lose them!. Clean up everything carefully and reassemble with out turning anything up the wrong way... lubricate everything and sit the cap back down. Hope thats detailed enough.

Short of that... buy a duetz as they never break down

 

[Tractortech]

Now Then..
If you have rusty balls,,, you're better off replacing them & greasing well... See the relevant page on JD parts.. AL153258 Repair kit, item 1..

 

[milkloss]

Thanks chaps. Yes we have float but it wants a ruddy good snatch to get it out. Well I actually took the cap of to get it out of float in the end; I had that 'you're gonna f**k it if you do it that hard' feeling.

When you turn the black cap it feels if nothing is occurring and I am guessing my balls are just too rough to engage/disengage despite my cleaning efforts?

 

[NZ Tech]

Keep up the ball cleaning... you'll get there on the end! .

Or measure them up and replace them. The kits aren't really cheap.. or expensive... up to you.

 

[milkloss]

Keep up the ball cleaning... you'll get there on the end! .

Or measure them up and replace them. The kits aren't really cheap.. or expensive... up to you.

Thanks, been on the phone this morning. £111 for the kit which includes 4 balls and the needle with collet and spring.

Still, it'll save me polishing my own balls, nobody else wants to do it!

 

[Timbo]

Common selling item, they'll have loads. Ask for 15% off.

 

[milkloss]

That's what I thought. Offered 10% to wait on stock order which is a bit unpredictable for my liking. So either they're on the shelf and fibbing or they really don't carry them which is surprising to be honest.

Edit: it is worth tapping a grease nipple in the housing when I'm done?

 

[Honest john]

Yes we grease ours, keeps the balls free.

 

[NZ Tech]

The grease nipple idea is a good one... Except someone will pump it so full of grease itll pressure lock... But if its just you.. Go for it . Itll help protect your balls.... When deep in the ah... Stopping there! .

 

[Honest john]

The grease nipple idea is a good one... Except someone will pump it so full of grease itll pressure lock... But if its just you.. Go for it . Itll help protect your balls.... When deep in the ah... Stopping there! .

There is some cut outs in the base of the ally bit that water can escape.
So locking up is not a problem. We drill greasers in them. Fill till it comes out of drain holes.

Oil can leak into cables which can stop you getting Float, or stop it holding into float.

Sometimes if you grease them & keep working it, they can if lucky sort themselfs out.

Cheers.

 

[milkloss]

Right gang, I'm back! I now have the detent repair kit and am probably more confused than before.

With the kit came a drawing of the assembly which is quite handy( I will post it in a minute as its on my phone) so I took both 200 series scv's apart to have a look see if something had been put back wrong before me.

As far as I could tell everything was right including the orientation critical component specifically mentioned in the drawing. The first scv had been well lubed with copper ease and balls all shiny and it has no detent in pump either way, I forgot to check float on this one. After I cleaned it up and replaced the old parts into the second troublesome one - remember I want the detent on this one because the flow control is not seized- and it still has no detent and I fail to see how shinier balls are going to make it happen. It has float detent but is tough as hell to pop back into neutral so maybe that is a symptom of some other issue? I assume because it's a bit rough the balls don't pop into or out of the 'orientation critical' collar?

As said before the 100 series scv works fine but no flow control

 

[milkloss]

 

[NZ Tech]

Hard to describe... But clean the scv parts thoroughly and remove any rust and scum that has formed. Make sure the spring pin is free and the bottom plate under the wavy/springs has a dot punched mark which must face up. Heres a picture that shows the break down better than the drawing they throw in the packet!!!. Make sure (o) is the correct way up as well... I think maybe yours is the wrong way atm. The lip faces towards your balls!. Hope that helps.

 

[milkloss]

Hard to describe... But clean the scv parts thoroughly and remove any rust and scum that has formed. Make sure the spring pin is free and the bottom plate under the wavy/springs has a dot punched mark which must face up. Heres a picture that shows the break down better than the drawing they throw in the packet!!!. Make sure (o) is the correct way up as well... I think maybe yours is the wrong way atm. The lip faces towards your balls!. Hope that helps.

Thank you that's great but; it does raise some more questions from me if you have the patience?!

All the relevant components sit on top of spigots in the ally housing and I have (from memory) from bottom to top:
-a washer
-wavy spring
-washer
-thick washer type plate with ears that engage the ally casing and a centre that prevents the 'ball holding piece' from rotating.(is this N in your diag?)
- a collar with the smallest I.D. facing up. ( as in cap that holds a tit on a babys bottle when it is standing up)
-balls!!!!
-then needle and four-groove collar together so the balls are encapsulated.

So which one of those items above has the dot punched in it that you mention as this sounds like the kiddy causing me grief?

 

[Honest john]

You have my symphathy, these SCV's are a pig to repair.

 

[NZ Tech]

Thank you that's great but; it does raise some more questions from me if you have the patience?!

All the relevant components sit on top of spigots in the ally housing and I have (from memory) from bottom to top:
-a washer
-wavy spring
-washer
-thick washer type plate with ears that engage the ally casing and a centre that prevents the 'ball holding piece' from rotating.(is this N in your diag?)
- a collar with the smallest I.D. facing up. ( as in cap that holds a tit on a babys bottle when it is standing up)
-balls!!!!
-then needle and four-groove collar together so the balls are encapsulated.

So which one of those items above has the dot punched in it that you mention as this sounds like the kiddy causing me grief?

"N" has the dot punched mark on it.

"O" has the ribbing on the inside that goes up towards ya balls.

 

[milkloss]

Despite everyone's efforts on here I still haven't managed to find the elusive detent. Spent several hours on it and still no detent on both scv's other than in float.

Feeling a bit despondent now; gonna find me one of these for the spool lever:

Much easier!

 

[Tractordave]

Go on, you know you want to!!!