[Kuraki]

My 430 has 2000 hours, and while it runs strong, cuts and blows like a beast, it is showing it's age. Everywhere there is linkage, there is wear. On the links that lift the deck, worn to the point where they would only lift the deck about 2". I repaired that, but did not take any pictures. Another big wear item is my transmission linkage. The machine is creepy crawly, sometimes creeping forward, sometimes in reverse. It lurches to speeds that I didn't command with the lever, and the only time it is consistent is when it's pegged full boar forward. Members here said, "check your linkage" so I did, here's what I found, and how I fixed it - without buying a thing.

If you look in the following 2 photos, you'll see they were right, my linkage is worn. My 430 is of the "type 2" vintage, with a hydraulic buffer in the steering column and a detent type neutral position on the hydro. This bar is what links the control lever to the rocker on the hydro. See any problems?

That's enough linear slop that I can move the control lever 5/16" before the hydro control valve begins to rotate, or, conversely, the control valve can rotate 5 or 7 degrees, freely, before the retention on the control lever stops it. Yes, I suppose I could order this part from JD, and drive to the dealer 40 miles away and pick it up, or pay to have it shipped to me, but I'm cheap, and I make things out of metal for a living, this is a simple thing to fix if you have the right tools.

You'll need a welder, a *** bar, and a drill press. Better yet, a milling machine. And in my case, in an effort to not buy any parts, a lathe.

This is the *** bar. It's a chunk of beryllium copper 1/2" thick 5x5" wide with a handle. It's used for putting welds where they have no leg to stand on. The weld will not bond to the copper, allowing you to do things like build up corners, or fill holes, at the full heat necessary to assure penetration.

Since this is a small part, rather than holding the bar, we'll hold it in the vise and clamp the part flat down to it.

Then, starting at the edge of the hole, fill the hole up by working the puddle first around the circumference, then in the middle, until you are above the top surface.

Here is the side that was against the *** bar. You'll see that there is some edge separation at the circumference. The copper is a heat sink, making penetration on the plane the copper is butted against very hard. That's ok, just weld over it. After cooling, grind both sides flush.

Here's the part I hadn't bet on. The shoulder nuts are worn eccentricly, over 0.020" That might be "close enough" but I don't want any slop outside of the necessary clearance for the shoulders to rotate. And I don't want to buy anything. I want to fix this tonight, not next week some time.

So, since I have completely welded up the holes, I can put whatever sized holes I want to, back in. I will turn the shoulders down on these nuts so they're round and slightly under the size I plan to drill the holes.

Now I will set the bar up in the mill to drill the new holes. You could do this on a drill press if you laid the holes out carefully. I don't know what dimension they should be, so I will put them in on the assumption they were centered on the radius of the outside profile.

A little burr removal and some paint, and here we are, back to spec. This took me about an hour to do. After installing it tonight, I can see that it will solve my problem, though I will have to readjust the neutral position. Now, every slightest movement of the control arm initiates corresponding rotation of the control valve.

:Tractor2:

 

[Harryc]

Impressive repair, and I wish I had your equipment. :fing32:

 

[coalminer16]

Agree-which I had your equipment. Unfortunetly for most of us we still need to use the OEM parts. Nice repair though.

 

[glenn27]

very nice repair--and a thorough explantion!:thThumbsU

Dealers hate folks like you, however-:dunno:

glenn

 

[Kuraki]

If the local dealer who is 5 miles away (and still my stihl dealer) hadn't gone cub cadet I would be much more willing to purchase parts. On the other hand some of these tractors are getting old enough that I worry about future availability at all.

Sent from the MTF Free App

 

[jar19800]

Nice shop! getting ready to work on my 318 linkage. i bought new because i dont have time to "repair" i do have access to plenty of equipment at work. plus the parts were pretty cheap

good luck! has this cured your problems or are there more worn parts?

 

[Kuraki]

Well, yes and no. This repair took out all of the play in the linkage between the control lever and the control valve. Now I get instant response from shifting the control lever position, as well as "full speed" reverse (about 1/2 of full forward) when prior to doing this I could only go about half as fast as should be possible.

However, I still have a surging issue. When I set the speed in forward to say 1/3 of full speed, the tractor lurches forward, pauses, lurches forward, pauses, etc. This condition does not "even out" if left at 1/3 speed. If I move the lever up to 1/2 or better forward, it then evens out and I have a constant ground speed. (This does not occur in reverse). Also, when compared to other hydro tractors I have owned or do own, there is no "smoothness" in speed change. Speed changes are instant back-jarring events that is only moderated by low engine speed. At full RPM, levering down from full forward to half forward will actually result in locking up the rear tires briefly, until ground speed catches up to the commanded hydro speed.

Third, when going down hill or into a dip, the ground speed will accelerate until level ground is hit, then ground speed abruptly slows down until the hydro "catches up" and then progresses normally at the commanded speed.

Unfortunately, given that my linkage is now up to spec, and my fluid and filter have been changed twice, and my relief valves seem to function properly (can index the poppets freely by hand) I am at the point of believing that the transmission is worn to the point of requiring a rebuild.

 

[jar19800]

mine kind of acts like that too i got real annoyed the other day backing over a gopher hill to hitch the plow and the tractor kept rolling forward off the "hill" i thought it was loose linkage, but after reading where you have the herky-jerky and speedups and downs i am wondering about my unit as well. i changed the oil in the unit and it had some goop at the bottom and on the drain plug. put on a filter and started tearing it down to get at the linkages so i do not know if the fluid change had any effect.