|
|
Northwest Ohio | We need to rebuild several SCV's on 40 and 60 series Deere tractors. Aside from leaking (SCV on vac system leaks a lot), they operate just fine. Looking for thoughts on scope and degree of difficulty. Right now, we're of the belief that only O rings need to be replaced. Better to know otherwise before we tear into these. Thanks, guys. |
|
| |
|
Between Omaha and Des Moines, 7 miles South of I80 | You need to tell us, WHERE is it leaking oil at. Does it only leak when the hyd. hoses are plugged into the SCV? (Might get by with just #1 and #2, on this photo = no disassembly needed) Does it leak when nothing is plugged into it/them?
 (RXP6606________UN06OCT94_ JD seal Kit photo.gif)
Attachments
----------------
 RXP6606________UN06OCT94_ JD seal Kit photo.gif (56KB - 391 downloads)
|
|
| |
|
Northwest Ohio | Small amount of leaking when tractors sitting and also when SCVs not hooked up. Much worse when in use. Not at farm right now, so I will have to wait to do a better job pinpointing leak. However, all leaking is coming out the back. |
|
| |
|
Between Omaha and Des Moines, 7 miles South of I80 | Sounds like you will have to install a seal kit, as a minimum amount of repair. See if you can tell, if any leakage is coming from the "ball/marble" inside the barrel; before you disassemble.(would require more parts) But my guess, is that #11 is leaking at the most rearward area. BUT, reading on here and speaking with JD parts guys (about a JD4440) they recommended reassembly with #9 and #10 seals (old style) VERSES the newer style of #11 seals. Reason is that the newer style (#11) tends to seep oil when tractor is sitting still and not running = that was my complaint to begin with on that 4440. {note: I found #11 seals where inside my SCV and I went back together using #9 and #10 = no leaks; but I did reseal the rest of the SCV with other seals in the kit, too} |
|
| |
|
Between Omaha and Des Moines, 7 miles South of I80 | If you don't have one, yet; go to an automotive store and get a $10 seal pick kit.
 (K4PSA_seal pick kit.jpg)
 (longer reach seal picks.jpg)
Attachments
----------------
K4PSA_seal pick kit.jpg (57KB - 348 downloads)
longer reach seal picks.jpg (5KB - 335 downloads)
|
|
| |
|
| Agree to use the o ring and backup ring set over the square rings. My 4430 leaked after rebuild with the square rings but the o rings fixed it.
INDY |
|
| |
|
Northwest Ohio | Thanks 4WD and Indy. Will take your advice. |
|
| |
|
| Also take the box off the tractor to rebuild. The first ones I did on the machine and man was I stupid. A lot easier on the bench to do.
INDY |
|
| |
|
Between Omaha and Des Moines, 7 miles South of I80 | Here's another photo, that shows more pieces. Those 2 expansion plugs, #26 in this photo, will have to come out. How I did mine, was to drill a small hole, about 1/2 way between edge and center, of expansion plug, then insert punch/drift into hole and pryed sideways. {Kinda wonder if there would have been room/clearance to have a small punch/screwdriver come in from the bottom(by levers) and punch them out ??? = then it would eliminate drilling, I never tried it.} On reassembly; you put those expansion plugs in with convex side UP, then I took a small, deep socket (like 3/8" or 5/16") and slightly pound in the center of new expansion plug = this pounds down the convex part and widens the plug's outer circumference, thus making them say "in place" = snug in its bore. Question for anyone: Has anyone left that upper, 4 bolt cover in place, and just done the barrels only. Basically, you would be slight hindered dealing with the expansion plugs and the 2 spring-loaded snap rings, but it might be worth a try? {note: there are many more spring-loaded valves and seals under that 4 bolt cover = it would be nice to not have to deal with those, if one doesn't need to, just when resealing barrels only.}
 (RP1455_________UN01JAN94.gif)
Attachments
----------------
RP1455_________UN01JAN94.gif (68KB - 366 downloads)
|
|
| |
|
SW Ohio | I have done several not taking the 4 bolt cover off, and some applications have the lower section as a complete unit with the valve located elsewhere (2840 JD for instance). No problem with the plugs, drill and pop as posted above, or just mangle with a chisel, needle nose pliers for the Jesus clip and assorted snap ring pliers and picks for everything else. |
|
| |
|
Faunsdale, AL | Couple of pointers...........
If you are working with one that has been converted to ISO barrels, the operating levers will be pinned onto the small vertical shaft that runs up through each barrel. Drive out the small roll pin that holds the lever on and then you can drive the soft plugs out the top of the SCV by tapping on the bottom of the shaft where the lever was removed. Many times the leak is only on that shaft with it's two tiny o-rings and backup rings and you can replace them from an o-ring kit. The soft plugs will go right back into place and seal just fine with a smart tap with a hammer in the center.
If you are only working on the barrels, you can avoid removing the cover with the flow control lever through it on those converted SCV's by taking the lever off the flow control shaft. It is held on by a tiny roll pin. Do not turn the shaft before putting the lever back on as it is possible to get the lever on backwards and mess up the flow control function. Fast will not be fast etc. Once that lever is removed, the operation shaft will come up through the top where the soft plug was. If working on original style with welded steel operating lever/shaft, it must come out the bottom anyway, so you can easily get the E clip off the top of the shaft without removing the cover with the flow control shaft through it.
On converted units, the snaprings retaining the barrels in the housing at the back are sometimes hard to remove. Two screwdrivers or a screwdriver and a sturdy pocket knife will get them out. Take a screwdriver and wedge between the barrel/collar and the snapring and prevent it from twisting in the housing while you pry the opposite end out of the groove. Many times, the whole ring just spins in the groove as you pry up on the ends with a single screwdriver. |
|
| |
|
Northwest Ohio | Thanks again, guys. |
|
| |
|
Wardview, LA | So is it possible to have an internal leak on the scv valve? I am losing pressure on my JD750 drill and I never thought to check the remote. Ive always used the one closet to my hand. I am going to run a test tonight but was curious if other have seen an internal leak? Kit looks pretty simple to install - is there anything special on putting it back together? do you have to set the opening |
|
| |
|
Faunsdale, AL | There are 4 poppet valves inside the housing that are operated by cams that the lever on the outside rotates. These can be out of adjustment or leaking. The puppets are not too expensive to just replace and the seats in the housing can be cleaned up with a set of stones made special for that purpose. The procedure to adjust is found in the service manual for the tractor or really any JD row crop tractor from the 30 to 60 series would be similar.
However I think you should be running with the lever locked into the down/lower position so minor leakage is not a problem. I don't always do that, just hit the lever every now and then to make sure the down pressure is maintained. |
|
| |
SCV Rebuild
