[jsaw]

312 will move forward but not reverse. Did some searches and hoping it might just be the linkage is worn..... does anyone have pictures/ suggestions or a diagram on how to trouble shoot this? Thanks

 

[trav1s]

JD, I have a service manual and can get you pics of that section. Look for an email from me.

Travis

 

[trav1s]

The first of the three is the adjustment procedure for your 312. If you don't get them I will try to resend later. Let me know.

Travis

 

[jsaw]

Thanks Travis! Got the email I appreciate it!

 

[trav1s]

Get any where on this?

T

 

[jsaw]

Not yet, have not had the time. Hoping to take a closer look this weekend.

 

[jsaw]

Now the 312 shutters a lot as you have it in forward position. Have not dug into it yet to take a look but thinking it now might be more then the linkage.

 

[trav1s]

When was the last hydro fluid/filter change?

That made a significant difference on my 120 and the 314 I sold.

 

[jsaw]

That's exactly what I was thinking to be the next step. I added some new hy-Gard and noticed in the sight tube the old fluid is very black compared to the new added.
Will change fluid and filter now and see how it goes.

The linkage does not seem worn as far as I can tell.

 

[trav1s]

Are you sure it has Hy-Gard in it? I have Type F in my 120 and that is what was in it before I got it. Not trying to open a can of worms either.

 

[jsaw]

Took off the fender pan and gas tank and one on the hydro release tabs is stuck it won't pop up. Could that be the problem? I am soaking it with PB blaster. I'm sure this has happened to others? What has the outcome been and what should I try next to release it?

I did not change to trans fluid yet.

Thanks

 

[gwc]

Yes JD if one of the release valve is not working then that can and will cause what you are experiencing. On my old 300 it did the same thing when one of the valves were stuck in the down position. Mine happened when I tried to push it with the free wheeling wheel pushed on the valve and when I released it one of the two did not pop back up after starting it. I took the one out and soaked it in PB Blaster over night an it popped back up. Then I took some fine sandpaper and cleaned the little pop up part and it worked as it should have. I do recommend that you should change the fluid and filter after you get it back running again though............Gary

 

[jsaw]

Thanks Gary- it looks like I can take a wrench or socket to the one that is stuck .... Is that correct? Does it unscrew ? Thanks

 

[hankvc]

JD, a few points.
First, if one of the release valve plungers is stuck down, the hydro won't work properly. You may have to take the valve out and work it (carefully) from the bottom.

Before taking any valves out (or taking the oil filter off), clean the outside of the area thoroughly so that no dirt gets inside the hydro.
Those valves should depress and pop up freely, and starting the engine puts pressure on them to come up.

I have no particular love for PB blaster, and much prefer Liquid Wrench or Nut Buster. Simply removing the valve and soaking it in transmission oil for a day will probably help free it up. The are O-rings inside the valve that don't like Stoddard Solvent (WD-40).

The dark color in the hydraulic oil you are seeing is probably Type F (red) transmission oil.
That's the earlier (and alternate) Deere spec for the transmission. You can drain that and refill with low-viscosity Hy-guard, although other manufacturers (New Holland, IH, etc) specify their regular hydraulic oil. The Sauer-Danfoss site lists several oils that can be used with the (formerly) Sundstrand type 15.

Hank

 

[trav1s]

Thanks for the post, Hank!

Good points to consider and hopefully JD will get some progress over the weekend.

Trav1s

 

[jsaw]

Thanks Hank-

Just tried to free up the valve with a 1" socket and drew some blood on my middle finger : ) It did not free up.

So instead I cleaned off the PB Blaster and poured a bit of transmission oil on it.

 

[jsaw]

Guess I will let it sit over night and see what happens. thanks again guys

 

[trav1s]

I fought my 120 when I put it back together with a similar problem. I think the ATF should do it but it might take some time.

 

[hankvc]

JD, those valves should unscrew from the transmission case. You may have to find a 6-point socket that engages completely with the hex on the valve.

I had this problem with my 318 when I got it a few years ago. As I recall, unscrewing the valves was no problem, and I just soaked them in Dexron and worked the plungers until they freed up. Stuffed some paper towels in the holes to keep any dirt from getting inside.

I had the hydraulic system open on that tractor for about a week, as I had leaks elsewhere to fix.
It had type F in it, which I drained, and was also able to work the two cylinders on the tractor to empty them. After I reassembled things (with a new filter), I refilled the system with lo-vis Hyguard, bled the system, and it's been fine ever since. The small amount of type F left in the system colored the Hyguard a bit, but no need to drain and flush again.

 

[jsaw]

Still struck. I have tried a few different penetrating oils with no luck. Might bring it to a guy with more tools and know how. Just thinking out loud. I assume heating the valve up would be a bad idea? What about welding a nut on top of the valve and wrenching it off that way? Thanks