520H/ Eaton hydro needs extra 1-2mph

[Greentored 3,217]

3 hours ago, WildmanC120 said:

It's well used. I would pull the motor and rear end from it. Great donor rear end for you. It's one of the few units where you will get the gears you want.

I may do that if I dont happen to scrounge anything up locally, soon.  Thanks!!

[Greentored 3,217]

1 hour ago, N875ED said:

Greentored:

Can you please send a photo(s) of your work...I'd like to do the same to my 520H

Thanks!

Here ya go!  I basically welded from the marker lines on the right, filled probably .200, then ground a steeper 'slope' to it. On the left side i laid the area between the marker lines back until it shifted in and out smoothe. Too much angle here and it would not shift out of reverse, it took a little finesse. The difference is day and night!  No more choosing fast forward/slow reverse or vice versa, just set neutral and let it rip!

[tom2p 2,394]

nice work greentored 

 

I have two 416-H 

 

one with fast forward / slow reverse 

 

one with slow forward / fast reverse 

 

ughhh 

 

 

Edited January 15, 2020 by tom2p

[Skipper 1,788]

You can theoretically slot the cam plate to go as many degrees backwards as forwards. That will give you the same speed in reverse though, so that may be a bit overkill. You have the 14 deg in both directions from absolute neutral.

 

Yes those are the gears you need to change. I would go for a nice condition HC rear end though. You should be able to find a complete running unit with the hydro and all for about a 150. Doubt you can find gears much cheaper. I may have a source for it if you strike out.

 

If you do not have enough travel on your hand lever, you can move the connection point of the push rod closer to the cam plates rotation point.

 

When you slot the cam plate, be sure to keep it nice and tight where neutral is, or it will be hard to find neutral without a bit of creep.

[Greentored 3,217]

Tom2P-

Well, Im about as green as they get when it comes to tractors so take any advice from me with a grain of salt and some additional research haha! I DO enjoy solving problems, and this worked awesome!  Id probably adjust both to a happy forward speed, then weld up the reverse slot to get that back. It all makes sense when you study the control plate- youll see neutral has a TON of plate travel before moving the pump arm- thats what I 'shortened up', on the reverse side. As Skipper talked about above, Eaton says no more than 14 degrees of pump arm travel- this is why I worked the reverse side- I dont know how much travel there is, but if its out of spec, we dont spend much time in reverse.....

Good luck and keep me/us posted on the results! If it works half as good as it did for me youll be one happy camper. 

Edited January 15, 2020 by Greentored

[Greentored 3,217]

Thanks Skipper! I certainly have time to look around and find a deal

PM incoming

[Greentored 3,217]

Just snagged all the gears from an HC on flea bay for 99 shipped! 

Thank you all, such a huge help!!!

[Greentored 3,217]

Gears arrived already. So much for 'not really a priority to do this mod.'

Never had one of these apart, but looks like I could jerk the left wheel and split the case right there in the tractor, a pretty straightforward swap?

Walk me through it, fellas.

[Greentored 3,217]

Parts have arrived, and in the meantime I did some farting around with numbers before disassembly and wanted to post this for others to read, as the 'slow 520H' seems not too uncommon.

***Please correct me if any of this is wrong.***

1. These transaxles have TWO gear reductions going on- pump gear drives countershaft 1 large gear, countershaft 1 small gear drives countershaft 2 large gear which contains the final drive pinion, correct?

2. From what you folks have explained here and whats been found online, the H used 20/46T gears, while the HC used 22/44T combos, all of them, from pump drive to counter 2.

Based on this, the overall drive ratio from pump to pinion would be 5.29 for a H, 4.00 for a HC- a 32% increase.   5.6mph x 1.32= 7.39mph, bingo.

With this being said, if someone did not need a full 7.4mph and/or could not source all the parts needed, it appears that only one of these gear sets would need to be changed for a milder 15% increase in speed.  20/46T x 22/44T = 4.60 ratio = 6.4mph.

Agreed this would be a lot of work for 1mph, but the remaining 1mph could be made up with tire size. 

Or do both, a tire size increase, rip the governor off and take it to Bonneville for qualifying 

Hell I dunno. Just rambling and hope someone on the interwebs might find this useful.....

[1990Onan520-H 15]

On 1/14/2020 at 2:56 PM, Greentored said:

Here ya go!  I basically welded from the marker lines on the right, filled probably .200, then ground a steeper 'slope' to it. On the left side i laid the area between the marker lines back until it shifted in and out smoothe. Too much angle here and it would not shift out of reverse, it took a little finesse. The difference is day and night!  No more choosing fast forward/slow reverse or vice versa, just set neutral and let it rip!

 

 

I'm a little late to the party, but do you have a picture of the finished product? I think I'm following what you did here, but want to be sure I understand. Would love to do this to my 520! I love the torque of the H's gearing vs the HC, but would love some more speed without hurting the torque to the ground, since I use my 520 more for grunt work than mowing.

[Greentored 3,217]

On 3/13/2020 at 11:52 AM, 1990Onan520-H said:

 

 

I'm a little late to the party, but do you have a picture of the finished product? I think I'm following what you did here, but want to be sure I understand. Would love to do this to my 520! I love the torque of the H's gearing vs the HC, but would love some more speed without hurting the torque to the ground, since I use my 520 more for grunt work than mowing.

That is the finished product haha. The sharpie'd areas are where I did the work, it is subtle.

The whole idea is to avoid the 'happy medium' where you end up with speed in one direction and slow in another. I basically adjusted the plate and linkage for 100% full forward motion (which indeed left me with almost zero reverse) then worked on the plate to get reverse back. This will not get you even close to an HC's speed, but youll definitely notice it. PS read my update below

Edited March 16, 2020 by Greentored

[Greentored 3,217]

**CAM PLATE UPDATE***

Now that I have used this tractor for a couple months with the modified cam plate, I do notice it is kinda finicky to find neutral. I have had the tractor suddenly 'creep' after sitting still for a few seconds, so just be careful, and lock that parking brake when the tractor is NOT creeping to keep load off the hydro.