682 Hydro Trouble??

[TEET]

Hi all,

I've been having a reoccurring issue with the hydro on my recently acquired 682...brief history: picked up the tractor from another forum member as a roller, and I dropped a K301 in it from a 1250...that I rebuilt. I did all the usual maintenance on the tranny, changed the hytran and filter which looked pretty good considering the tractor had been sitting for a while. I also took out the auto check valves and cleaned them well. When I first fired it up after the engine transplant, the hydro linkages seemed out of wack, so I patiently adjusted, and readjusted till it was driving flawlessly, with no leaks. Almost immediately the adjustments seemed to go out of wack...like neutral was going forward, and reverse was non existant...readjustd, and back to normal. This happed several times, so I decided to change the hytran and filter again, thinking it might have had some junk in there, as well as re cleaning the check valves. Same deal....good for a while then neutral was forward all over again....you get the idea.

I did make a couple of observations that may or may not be related...but...it seems that when the tractor is off it pushes pretty easily, compared to my 1211 which is virtually the same except for the hydro lift and aluminum rear. Also...I noticed today, when it was acting screwy again, if I turned it off, and pushed it back wards a few feet, and restarted it..it was back to normal.

Is this weird, or am I missing something simple? The first thing that comes to mind is the check valves are shot, although they don't leak, and do the same thing regardless which side I place them in.

Edit: Forgot to mention, that the trunnion is in excellent shape with next to no wear....

Any ideas?
Thanks,

Jeff (teet)

[ajgross]

I would check and make sure that the plate that runs vertical on the trunion piviots freely. The shaft that it pivots on can get a little rusty and cause it to hang up. Hope this helps.

AJ

[Matt G.]

It will also do that if it wobbles side-to-side on the trunion shaft. Get some shim washers to put under the snap ring.

[TEET]

Thanks Matt, and AJ...I think you guys are on the right track with the trunion. I shot it with some PB last night, and worked it both ways this morning, and it seems to be better, but it does have some side to side movement on the shaft. I'll try to round up some shim washers and take some of the slop out of it.

Thanks guys

Jeff (teet)

[TEET]

Well.......jsut a little update on my tranny woes.

I cleaned up the shaft, and it moves smoothly now, as well as adding 1 shim washer under the snap ring, which was not easy to get to might I add while the tranny is still in the tractor....anyhow, after doing this, and readjusting it for the zillionth time, it was driving perfect today. I ran it around the yard for an hour, and it was flawless.

BUT...

I parked it in the yard for a bit while I swept out the shop, and moved my other Cubs around and when I came back out a couple hours later to move it back into the shop..yup...back to being screwed up again. I don't know how this can happen from just sitting for 2 hours. Neutral was almost all the way in reverse, reverse was non existent, and forward motion started way below neutral.

I'm beginning to think that something is not kosher in the pump itself or the check valves are shot....but I thought they leaked when they went bad. These are as dry as a bone, and the internals moved freely when I took them out and cleaned them.

Guess I'll be tearing the pump apart for an inspection...not looking forward to it.

Jeff (teet)

[Matt G.]

Can you swap the relief valves with known good ones? Also, you might change the filter again...I had one clog a filter and do strange things like that.

[TEET]

Thanks Matt, I thought about swapping the ones from my 1211 in it, but I got frustrated enough for today and just rolled it back into the shop...I'll give it a try tomorrow.

This might not sound too smart, but is there a way to either clean or flush out a filter? This will be the 3rd filter I've bought in 2 weeks (1 for my 1211, 1 for my 127, and 1 for the 682) and I'm running on a tight budget at the moment.

Jeff (teet)

[jbollis]

TEET,
It almost sounds to me that your swashplate is moving on you. The Trunnion shaft is 2 pieces, it does not run all the way through the case. Try putting a mark on both shafts (sides) in the same spot. Then run it until it acts up again and make sure the marks are both in the same relationship with each other still. This will tell you if the swashplate has come loose on the shaft.

I think I explained that ok, I know what I mean just can't put it words so well.



JOE

[TEET]

Thanks Joe,

I understand what your saying. I just replaced the trunion side seal on my 1211, so I had that pump apart and am familiar with its workings. Sounds like your on to something with the swashplate....cant wait to tear into it!


Jeff (teet)

[TEET]

Well...I have an update on my 682 hydro woes. I finally had a chance to pull the rear end, and remove the hydro pump, and I figured out what the problem is.

At some point in the past, either a previous owner or IH dealer replaced the trunnion shaft, and in doing so only replaced one of the 2 required "in-line" roll pins that attach the shaft to the swashplate. I see now why there were 2 there from the factory. The one that was replaced wasn't centered properly and caused the upper hole in the swashplate to wallow out...there was a lot of play in it, and now I know why.

You can also see in one of the pics that when they were driving out the roll pin on the other end of the swashplate, that they must have gone nuts on it and drove it through the outside of the pump housing. They drilled, tapped, and used loctite on a setscrew in the hole. My dealer long ago warned me about being very careful while tapping these out as they often have to repair them for customers that go to town on them.

Now heres my dillema...the swashplate is NLA from Cub Cadet, so I either have to find a used one, or just find a different pump all together....ugh..

I also noticed that the pin that captures the gear for the charge pump was also tweaked on both ends...and to make things worse the brake plunger o-ring just started leaking...what next.

I know that the swashplates have different part numbers from model to model, but I don't know what the real differences are with them.

Anyone have a spare, junk, or "parts" pump they want to get rid of cheap? Or even just a swashplate?


Jeff (teet)