Parking Brake Adjustment

[Porkskin 20]

Working on:  1986 Wheel Horse 312-A, Model 21-12KE02, 42" Deck Model 05-42MR04

 

Hello All, 

 

Well, the parking brake on this one stopped working, and after removing the shift plate it was clear that the pawl was no longer reaching any of the teeth on the bell crank. So I figured I needed to adjust the travel on the rod that accentuates the squeeze on the brake lining. It's not perfectly clear to me where the adjust point is, but I think it is the bolt-nut-spring assembly as shown on the pictures attached. Now, if that is the bolt I need to put some clockwise turns on to get this done, the question becomes how can I get a pair of 9/16" wrenches or sockets in there to make the turns. I pretzeled myself in several ways to get tools on both ends many ways with no luck. All comments very much appreciated.

 

I'm using these diagrams:

www.partstree.com/models/21-12ke01-312-a-toro-garden-tractor-1986/index.html

 

The first picture is taken from the right side inward toward the assembly. The second is taken with me on my back looking up.

[Handy Don 12,167]

1 hour ago, Porkskin said:

Working on:  1986 Wheel Horse 312-A, Model 21-12KE02, 42" Deck Model 05-42MR04

 

Hello All, 

 

Well, the parking brake on this one stopped working, and after removing the shift plate it was clear that the pawl was no longer reaching any of the teeth on the bell crank. So I figured I needed to adjust the travel on the rod that accentuates the squeeze on the brake lining. It's not perfectly clear to me where the adjust point is, but I think it is the bolt-nut-spring assembly as shown on the pictures attached. Now, if that is the bolt I need to put some clockwise turns on to get this done, the question becomes how can I get a pair of 9/16" wrenches or sockets in there to make the turns. I pretzeled myself in several ways to get tools on both ends many ways with no luck. All comments very much appreciated.

 

I'm using these diagrams:

www.partstree.com/models/21-12ke01-312-a-toro-garden-tractor-1986/index.html

 

The first picture is taken from the right side inward toward the assembly. The second is taken with me on my back looking up.

 

 

Hi.

 

Firstly, adjusting that nut is much easier with the footrest off the tractor.

 

Secondly, is the brake itself still working? Must the pedal be very deeply depressed to make it work? Is the issue you are having that all of the teeth of the parking brake pawl have rotated past the parking lever?

If no, yes, and yes then the problem lies elsewhere. It may be that the brake linkage has become disengaged from the parking pawl.

 

Here are some diagrams I posted for another member who had a similar problem.

 

You can ignore the part about motion control, as that applies only to hydros. But the other parts of the linkage should be the same in your 312.

 

 

[gwest_ca-(File Mod) 11,033]

The parts list for the 1986 models included a few pages of service information. The 2nd page of this file covers the brake adjustment

Garry

[Porkskin 20]

Thanks Guys. Not seeing that I could have simply removed the foot rest to get at this makes a big difference. When I received the tractor a couple of months ago the brake worked as well as the parking brake lever. Between then and now there was not much use of the brake pedal but somehow the parking brake lever stopped grabbing teeth.  So the brake still operates, but it does seem that I have to press deep to get drag.

[Lee1977 6,648]

On the older wheel Horse models if the brake band is adjusted too tight you can't push the peddle for enough to engage the parking brake. Even tho the linkage is different I think it would be the same.

[Handy Don 12,167]

On 6/25/2021 at 11:11 AM, Porkskin said:

Thanks Guys. Not seeing that I could have simply removed the foot rest to get at this makes a big difference. When I received the tractor a couple of months ago the brake worked as well as the parking brake lever. Between then and now there was not much use of the brake pedal but somehow the parking brake lever stopped grabbing teeth.  So the brake still operates, but it does seem that I have to press deep to get drag.

I should have asked first: "When you step on the brake, does then motion control go to neutral?"

If NOT, I'd go back and make sure that part #7 in the diagram is actually going through and connecting to part #26, the parking brake pawl and motion control centering mechanism.

If YES, then I'll agree with @Lee1977 that it is the adjustment on the brake band/spring that needs tweaking, the brake drum as gotten a layer or rust, or else there is some debris keeping the band from tightening correctly. Personally, I adjust so that I have to press pretty firmly on the brake to get enough movement to engage the parking brake.

[Tuneup 1,433]

Why not take this opportunity to refresh the lining? You might find that you can easily adjust it according to the manual procedure. The lining is sold by a poster here - heck, it's an old machine so it's almost a guarantee the lining is worn.

[Handy Don 12,167]

3 minutes ago, Tuneup said:

Why not take this opportunity to refresh the lining? You might find that you can easily adjust it according to the manual procedure. The lining is sold by a poster here - heck, it's an old machine so it's almost a guarantee the lining is worn.

Good point. @rmaynard is the "brake lining guy"

[Porkskin 20]

I did get to thinking about how best to replace or refurb the band and saw the brake lining mentioned. I may go with that, we'll see. For now I want to get some grass cut and have found that I really need the parking brake to work on inclines. 

 

1. The brake works when the pedal is pressed and the band cinches up fine. I note this also moves motion control to neutral.

2. Checked for the missing cotter that Handy Don mentioned, and mine is in tact. It's more like a hitch pin on mine than a cotter.

3. Today now that I can actually get to all the parts I can get the pawl just as far as the most rearward notch on the pawl. I could do this only by turning the locknut left wise to the point where the end of the bolt starts to miss the locking part of the nut. See first image and arrow. Second image shows the pawl engaged as I mentioned, and you can see one or two of the frontward notches under it.

 

So if I need to loosen the band to allow a bit more throw of the whole brake system I need to figure out where that adjustment point is. I'm failing on that one right now. I'd be happy with just a quarter inch of give so that I could follow the adjust procedure as stated in the manual.

 

[Handy Don 12,167]

19 minutes ago, Porkskin said:

I did get to thinking about how best to replace or refurb the band and saw the brake lining mentioned. I may go with that, we'll see. For now I want to get some grass cut and have found that I really need the parking brake to work on inclines. 

 

1. The brake works when the pedal is pressed and the band cinches up fine. I note this also moves motion control to neutral.

2. Checked for the missing cotter that Handy Don mentioned, and mine is in tact. It's more like a hitch pin on mine than a cotter.

3. Today now that I can actually get to all the parts I can get the pawl just as far as the most rearward notch on the pawl. I could do this only by turning the locknut left wise to the point where the end of the bolt starts to miss the locking part of the nut. See first image and arrow. Second image shows the pawl engaged as I mentioned, and you can see one or two of the frontward notches under it.

 

So if I need to loosen the band to allow a bit more throw of the whole brake system I need to figure out where that adjustment point is. I'm failing on that one right now. I'd be happy with just a quarter inch of give so that I could follow the adjust procedure as stated in the manual.

 

 

 

Yep. My brake adjusting nut is also right at the end of it's "locked" travel and the parking lever also grabs only the "last" notch in the pawl.

The only way I can see the nut being tighter is to offset wear in the brake band. My band has almost no wear at all so I'm "at the max".

Interesting about the clip--that is not the stock part so someone's been in there before you! 

[pfrederi 17,676]

I do not have one of these but looking at the parts manual just shows a normal bolt 4.5" 3/8NC..Why not get a 5" bolt....

[Porkskin 20]

I know it was unconventional do this, but I replaced bolt #26 with one that was 1/2 an inch longer. Works fine but still interested in knowing how to adjust the band so I'll be ready for that. Thanks to all as usual for being here and commenting.

[Handy Don 12,167]

As the brake lining wears, you'll tighten the bolt pointed to by your white arrow. I suspect you'll be able to notice when brake pedal travel farther forward, or the parking lever engages notches farther down on the pawl--or when you hear a loud squeal!

Unless your brake lining has deteriorated from weathering or worn from very heavy use, that will take quite a while.

Edited July 9, 2021 by Handy Don

[Porkskin 20]

Thanks Don, A nod to pfrederi whose comment I missed until today, but whose idea about the bolt was the trick for me at this point.

[Handy Don 12,167]

Good to hear you're ready to button it back up. You can now tackle the slopes with confidence.

 

FWIW, I've learned that the tractor will engine brake downhill even with the hydro--just don't think that putting it in neutral will cause it to stop (yeah, that was a terrifyingly exciting few seconds as it picked up speed until I slammed on the brake!)