Case 530 580 7 others...The governor control linkage is?

Fellas I sure could use some help understanding how this linkage works........My late 60's Case 580 (same as 530 for this question) runs great but will not throttle up correctly and I discovered that the guide/stop plate that affixes to the block and connects to the double springs for the gov is broken. The small stop tab on the guide bar is missing. PART ILLUSTRATION # 18 in the Case online parts reference for 530 Tractors.

I understand the double springs; the little one inside the bigger one and I am certain that these hook into the guide rod assembly as shown in the illustration and provide tension when applying throttle but do not understand how the guide stop slider plate factors in to the operation of the throttle linkage and will allow me to go past high idle as that is all I can get with the slide stop bar not attached....does the plate stop the guide at the stop and then allow one of the two springs to react opposing the other and somehow push the throttle open further?? I can not see how the addition of the slide stop will help me control the throttle UP past high idle.

I hope my question is framed in a manner that makes sense. Simply put I increase throttle and get very small increase even though the throttle linkage is moving a great distance but not enough to cause the carb linkage from the gov to move enough.....now I know I do not have the broken guide plate stop bolted on yet but I am missing how that will help push that linkage ahead further to allow the gov linkage to open the carb bigger. The case parts drawing seems very simple but I sure am thinking I am missing something.

I am gonna weld a small tab on the guide stop plate to fix it and reattach to the block but that part seems to be designed to control how far BACK the throttle can be pulled and my problem is i want more??? Can you help by explaining the way this is supposed to work ? Thanks

(reply to post at 19:58:10 03/21/10)

Click to expand...

The problem not getting high rpm could be that the throttle shaft could be rusted tight in the bearing where the shaft goes down into the governor housing, a common problem. I just freed one of those up a couple weeks ago that had the very same symptoms which you describe. Get some PB Blaster or other good penetrant and soak the area up where the shaft enters the front cover then work it by hand and work the penetrant in. You may have to work it a while for it to free up, then soak it with oil and work it in. It may help to get more swing on the arm by unhooking the carb linkage till it is freed up. You can repair the high rpm stop but it is not the problem. The springs work with each other, one adding to the pull of the other. The spring side pulls back to increase the rpm so I'm a bit confused by that part of your post. Once everything is free the linkage rod ball joint should be adjusted so that with the throttle wide open the carb lever stop ( the side opposite the idle screw) should be 1/16 off the stop pin. Post back if you have any info for us. mEl

Well that sure makes sense.

I know the shaft moves BUT I bet the pivot arc is not enough..... I was looking at this broken high throttle guide, springs & stop as the culprit all along and never thought that I could have TWO problems with the linkage and gov as it was running good before the double springs and stop needed to be fixed.

Come to think of it.. Those double springs were not quite the correct OEM type. I bet somewhere along the history of this old tractor someone fixed the tight shaft by putting MORE pull against that pivot shaft assembly I will soak it good and free the shaft a bit and see if I am lucky. I hope the pivot assembly does not need replacing as that looks to be a chore.

I will let you know and thanks for taking the time to reply.

This post seems familiar...think I've responded before.
The governor/throttle works like any other system, a balance between spring/positioning loading and the centrifugal weight action of the governor.

Problem with these Case units is that the governor shaft (that slides in and out on the end of the camshaft) tends to take a set or freezes up completely so that travel is either limited or none.
That's why you can't get enough throttle no matter how hard you pull the spring.
Not much you can do about it unless you want to pull the front cover, investigate and repair.
On mine I made up some direct acting linkage that bypasses the governor and it has been working in that mode for about fifteen years now.

I would be quite interested in how you did that linkage to get around the sticky governor. Thanks for the reply.

Am interested in anyone's alternatives to bypassing the governor on the Case 530... i have the same problem with mine right now.... will just jerry up a hard throttle cable on it for now... but interested in what others have done