1990 520h Trans is Jerky from Fwd to Rvs

[Duramax7man7 505]

Hey all,

 

 So, I've been using my 520 off and on and although I'm still not done with all of the little tasks, one thing I wanted to focus on was the transmission.
 

 I experience quite a bit of jerkiness when moving the motion lever from reverse to forward, even when it's a slow movement of the lever. I have noticed that the cam for the speed control has flat sides on it instead of being round... Could this be what is causing the jerkiness? Or something else?

[bmsgaffer 2,043]

The cam follower sounds worn and also the cam plate will have the curves worn down and that makes it hard to control as well. Also you will have to check the linkages from the lever back to the cam as they can get wallowed out and that will also cause jerkeyness.

[Duramax7man7 505]

Thanks! The linkages all seem good to go. So I will hunt down a good condition cam. Maybe it will come with a plate... Thanks for chiming in.

[cleat 4,947]

And install Matt's foot control. Jerkiness gone and smooth transition from forward to reverse with a tap of the toe.

[DougC 2,641]

And just a thought here. Change the oil and filter in the hydro at least once a year and use a good quality 10 w 30 oil your choice.

Warm up the hydro first and get ready to have some fun with the refill......   

[Duramax7man7 505]

Unfortunately I dont have $250 at the moment. And I just chanfed the filter in Nov 2016 and I couldnt get the plug out. I think that it go bumped and smashed a bit by the PO. I will change it this spring. I did top it off though as the axle seals were leaking. There is a leak coming from the motion shaft on the eaton 1100 but I have a seal that I ordered waiting to be installed. Its a slow leak though. Thanks for the tips though. 

[smoreau 658]

Pull the large suction tube off the bottom of the trans to drain the oil. Its on the right side just infrot of the axle tube.  Had to do it for the same reason in the past.  When I'm changing oil from conventional oil to Mobil 1 I remove the filter, mount a long funnel to the housing to a drain pan and with the tractor on jack stands. The oil will come out of the filter housing with the engine running.  I run it tell it stops moving the tires and the lift wouldn't work. Then add 2 quarts of Mobil 1 and start it back up and run it tell it stops again. Install a new filter and top off with Mobil 1. Many people freak out by running this out of oil will damage the pump, no it will not for this short time. These are hydraulic systems, not engines. This is just a way to flush the system to get all the fluid changed out.  Common practice in small systems like this. Anyway it works great and the Mobil 1 works great in every one i have done it to. 7 Eaton's and 3 sundstrands. 

[Duramax7man7 505]

WOW, yeah that's a great idea. Thanks for the pro tip!  

I will definitely do that but I still want to get that plug out. it bugs me just thinking about it. smh...

[smoreau 658]

Another tip tie to pull one of the seat pan bolts that hold the seat pan to the axle. This will allow you to be able to fill the trans much faster. It will take around 4-5 quarts depending on how much comes out of the pump. Most times its 4 quarts in my experience. 

[Duramax7man7 505]

Yep. Figured this one out when I filled it the first time. Pulling that one bolt makes a world of difference. I've also stuck a straw down the tube on one side and that allowed the air to escape while the oil was going down the tube.

[Duramax7man7 505]

Okay, So I replaced the motion cam even though there wasn't very much play at all in the old and the issue still exists. I hear the trans grunt a bit when I move it from forward to reverse or reverse to forward when it jerks.

 

Am I looking at a issue with the Pump? Maybe some type of gummed up system?

 

 Looking forward to replies. Thanks!

 

Andrew

[Duramax7man7 505]

Okay so if everything is in properly adjusted order, could the non smooth transitions from forward to reverse and vs versa be caused from one of these valves? Looking at the manual... It seems that something like this could be a problem if over warn and could easily be replaced to fix the issue. 

 

1. Check Valves

2. Pressure Relief Valves

3. Acceleration Valves

[bslms 19]

Just some thoughts on Mobil 1 as a trans fluid.  I have a small lawn mowing business for which I use commercial mowers with hydro pump and motors.  The original spec fluid (in 2006) was Mobil 15W-50.  Around 2010 the Mobil was pulled as a recommended fluid.  Apparently with the increasing emissions standards the formula for the Mobil had to be altered to remove some of the ingredients beneficial to hydro systems, mainly zinc, because it affected the catalytic converters.  I am sure that it is an oversimplification for the sake of explanation.  Anyway, newer fluids have been developed to include the important ingredients in hydro fluids.  These can be had at dealers that sell commercial mowers, I use the Exmank brand but almost every manufacturer has their own version.  

In my experience, the true hydro fluid produced noticeable improvements in terms of smoothness and response, especially when hot.  This fluid is expensive, but, the manufacturers have doubled the service interval so it works out to be very close in price.  

Just food for thought, especially if you have a horse that works hard.  Show tracs will probably never see a benefits.  Might be worth a half an hour on the net to look into. 

[rmaynard 14,888]

I use Walmart brand synthetic 10W30 in my Eaton 1100. Works great. I also had the jerky motion on my 416-H, so I replaced ALL the linkage parts, cam, follower, etc with no appreciable change. That's when I changed over to Matt's foot pedal. It was an investment that I really did not have the money for, but found a way to do it anyway. It makes all the difference in the world. Will never go back to the design that Wheel Horse used originally (hand control). 

[Duramax7man7 505]

Thanks to you both... 

 

ramynard, 

 

 Were you just experiencing the jerkiness when switching from forward to reverse? That's all that I'm getting and the rest is smooth. I don't understand why switching to matt's foot pedal would change anything. Can someone explain this? I'm not the kind of person to switch to something because everyone else says so or has done so. I'm not trying to offend anyone or anything. I'm just typically someone that likes to figure out problems instead getting around them. Not meaning to offend anyone!?

 

 I just don't see how spending the $250 for that pedal setup would fix the eaton 1100 issues. being that I've tightened up all the linkages as well as replaced the cam and set the neutral up perfect. There's no play in the linkages and I hear a slight grunting of the eaton when I get the jerk. 

P.S. I don't use Mobile 1 in the trans. 

[rmaynard 14,888]

My problem was that switching from forward to neutral and reverse to neutral actually was like hitting the brakes. There was no gradual slowing to a stop. Even going from full forward speed to a slower speed felt like I had hit the brakes. 

 

I agree that you should explore all possible options before investing in the foot pedal solution, but for whatever reason, the foot pedal did the trick for me.

 

Good luck!

[Duramax7man7 505]

Yeah that's pretty much what I'm experiencing... It's only when switching directions. I don't throw it in either direction though. If I moving forward close to neutral and drop the speed quickly it will jerk.

 

I can move the level down in speed in either direction but once I get close to neutral and then try and switch directions, it's like it wants to engage in the opposing direction to quickly and jerks toward that direction.

 

[WHX?? 46,728]

3 hours ago, rmaynard said:

the foot pedal did the trick for me.

I'll second that.  I bit the Matt's bullet for convenience sake but it did cure my same as your jerky issue. Before I put on the pedal I clean & lubed & re-bushed all the linkages to no avail.

[Duramax7man7 505]

It'd be nice if there was a full explanation why it does this.

 

[WHX?? 46,728]

2 hours ago, Mastiffman said:

It'd be nice if there was a full explanation why it does this

I hear ya buddy... I wrestled with this issue for days & days. Thought it was just an adjustment issue when it was new to me. I musta had that tunnel cover off a dozen times  I could be wrong but I think it's got something to do with the design of the motion lever & linkage & that's why it went away with the install of the pedal kit. Anybody know if say a 416H does this too? My 416 came with a pedal. Come to think of it I did switch to mob 1 10w30 syn at the pedal installation so maybe that helped

[rmaynard 14,888]

See my post above. My 416-H was a culprit. I don't think it has anything to do with the model, just the way the Wheel Horse linkage/cam works on the Eaton 1100. Once all the front linkage was removed and replaced with Matt's linkage, the problem went away. As far as the cam tensioner nut, I loosened mine up completely, and lubricated everything, just as it says NOT to do.

[Sarge 3,462]

If you can set it up on jack stands safely and run it through both directions while watching the cam that would show if the cam arm suddenly jerks from a bind or whatever . A long stroke dial indicator would really get it down to watching the range of motion and noting any sudden changes while moving the direction lever . All it takes is one little bind to cause things like this since that valve moves so little through the entire range . I always wished the valve levers were designed longer both on the Eaton and Sundstrand transmissions to make the geometry work smoother than the way they were designed - just a little wear can create big problems . Also , any gunk in that direction valve compounds the issue , so the oil itself is very important . I have two identical older Sundstrand piston to piston units - one is smooth as silk , the other wants to launch you off the seat and can be downright dangerous at full throttle .

 

Sarge

[cleat 4,947]

I believe what you are feeling is normal if you move the lever very fast at all.

 

Neutral setting blocks oil flow and effectively locks up the drive motor therefor locking up the rear wheels.

 

Any hydro machine I have owned with the eaton 1100 has worked the same way.

 

My old Ford had foot control and if you were going full speed ahead on the gravel drive then sidestepped the pedal so it snapped into stop position, it would skid the back wheels.

 

You either need to be very careful with the hand control or if you do switch to foot control (as I have with all of my 520's), then you just seem to naturally lift off the pedal as opposed to sidestepping it.

 

Foot control does not change the transmission, only how you tend to operate it.

 

Cleat

[Duramax7man7 505]

@Sarge

 

 Everything is smooth moving so I'm guessing that it's just partially the way they operate. But being that the drain plug was smashed a bit and I wasn't able to drain the oil. I will be accomplishing this when it warms up. Could just need completely fresh oil. I'll have a couple of things to do as well being that the seal for the cam arm on top of the eaton has a little leak and I think that my hydro cylinder needs to be rebuilt as well. It drops over the course of a day...

 

 @cleat

 

 I'm not slamming the motion lever at all. If I'm moving forward or reverse and pull it back to neutral even, I get the jerk symptom.

 

 One thing that I'm thinking is that the "Auto Neutral of the foot control may help in bring the trans back to a neutral state more smoothly. Kind like when I feather it back with more of bumping motion instead of a single slide? I was looking at the parts and install instructions and that's the additional spring that Matt provides with the kit stood out to me about it all.

 

 So the plot thickens... I will keep you guys up to date on all that I do with this issue over time. I don't know how soon I'll get to it until it's warmer out though.

[Duramax7man7 505]

Alright so here is the video I took this afternoon. Is this to much play? I used the tractor this afternoon to remove a couple of mounds in our front yard from old trees that were removed and it seemed to not be as bad after a while using it but it was still there. Or I got used to moving the lever the way that avoids most of it...