Why change the PTO hoop clevis??

[Fiddlestix 0]

Like many of the members here, I have several models spanning various decades of Wheel Horse production. I noticed the extra steps needed to remove a belt from the mechanical clutched PTO of newer tractors. I reviewed several parts lookup viewers of several models. Right around 1987 mid year and newer, all models switched to a different clevis. This is the little clip that gets the hitch pin and transfers pressure to the little peg at the center of the clutch. Prior models had the "swinging" style clevis and the post mid- '87 gets the straight 3/4" (as WH calls it) that does not swing open.

The newer style requires that you drop the actuating pivot/arm from the top link, pull the pn at the clevis, pull the hairpin at the bottom of hoop, and now you can swing hoop out of way to allow belt to clear.

The old swinging clevis, you simply pulled the hitch pin from the clevis, swing the clevis clear of the pivot and swing the hoop clear.

With the superiority of Wheel Horse's Tachmatic system, why would they create a couple extra steps for no evident (to me) gain??? The hoop has the same amount of manufacturing ops, it is the same size, the clevis is so close to being the same, there can't be much of a cost advantage. I cannot see any safety issues being eased with the newer style.

The two styles interchange... I just swapped a 312-8 hoop w/ the older swinging clevis onto a 520H with the straight clevis and it fits functions fine. Now it is a single pin pull to detach/attach the belt.

Someone enlighten me on this oddity...please! :omg:

[markslawnmowerworld 4]

I know exactly what your talking about.......the anwser is TORO, wheel horse was purchased by toro in 1988 and soon there abouts things got cheaper on the tractors... :D

[Pirate 0]

Some "engineer" trying to justify his job?

[Red Horse 34]

Like many of the members here, I have several models spanning various decades of Wheel Horse production. I noticed the extra steps needed to remove a belt from the mechanical clutched PTO of newer tractors. I reviewed several parts lookup viewers of several models. Right around 1987 mid year and newer, all models switched to a different clevis. This is the little clip that gets the hitch pin and transfers pressure to the little peg at the center of the clutch. Prior models had the "swinging" style clevis and the post mid- '87 gets the straight 3/4" (as WH calls it) that does not swing open.

The newer style requires that you drop the actuating pivot/arm from the top link, pull the pn at the clevis, pull the hairpin at the bottom of hoop, and now you can swing hoop out of way to allow belt to clear.

The old swinging clevis, you simply pulled the hitch pin from the clevis, swing the clevis clear of the pivot and swing the hoop clear.

With the superiority of Wheel Horse's Tachmatic system, why would they create a couple extra steps for no evident (to me) gain??? The hoop has the same amount of manufacturing ops, it is the same size, the clevis is so close to being the same, there can't be much of a cost advantage. I cannot see any safety issues being eased with the newer style.

The two styles interchange... I just swapped a 312-8 hoop w/ the older swinging clevis onto a 520H with the straight clevis and it fits functions fine. Now it is a single pin pull to detach/attach the belt.

Someone enlighten me on this oddity...please!

EZ, I've thought the same thing. I thought I was the only guy who wondered why something simpler was made more unnecessarily more complicated. I've got an 86 308 with the simple PTO hoop and a 94 312-8 with the later more complicated hoop. It makes no sense! I need to find an older PTO hoop for the 312 :D

[Fiddlestix 0]

I laid the two types on the table and stared at it trying to think it thru. I have some background in machine work and manufacturing and I just do not see a terrific cost savings( which is usually why a proven design gets "improved"... newer in my experience is rarely better).

The heavy wire hoop is the exact same bends and proportions as the previous design and likely the same material and treatments. There are two drilled holes in each design... one for the lower hitch pin and one for the roll pin that secures clevis. The roll pin hole is clearly in a different location (on centerline with the clutch peg) that the old design (below centerline). Other than that the hoop would be manufactured on the same lines with the same fixtures and tooling... no cost savings.

Both styles of the clevis employ two 90* folds of the same gage steel and both require the same two holes. No substantial savings there. The old one is a tad bit more material but due to its small size even at 50% material difference it is not a substantial cost savings to warrant the complete new design tooling and fixtures as well as inventory logistics.

I cannot see any safety issues that were eased with the newer design. It would appear to me that Toro was not involved with this because the parts lists show this changeover occuring nearly a year prior to their takeover.

About the only advantage I can see is the swinging clevis may get tight if the roll pin holes weren't carefully drilled and the pin assembled just so. This could lead to a stiff moving clevis and somebody is going to break a thumbnail instead of using a screwdriver to pry the clevis out...certain disaster in today's litigious society!

I converted over both of the newer styles to the older clevis and have not experienced any issues. As mentioned, it is a step backward in the ease of attachment install/remove and goes against the wonderful strides that Wheel Horse made with the Tachamatic system.

Strange things there at south Bend! :omg:

[MalMac 1,333]

Well I am glad I am not the only one shaking his head over this.

[jsottile 0]

Does anyone have a part number for the older style that will work on my 520H? I just installed my deck today and I can't believe how they made the design so that you have to knock out the pin....

[TT-(Moderator) 1,169]

:omg:

We are talking about changing attachments on garden tractors here, right?

So you have to pull a second pin on some of the newer models...... is that extra 15 seconds in your pit stop going to cost you the lawn mowing championship race?

Three things.......

1) Don't blame Toro - give them credit for building 20 years worth of WH tractors.

2) Changing attachments on a WH is still easier than on most other brands.

3) The time it took you to read this post was more than enough to pull the "extra" hair pin clip out of the trunnion on the PTO engagement rod, drop it out of the triangle-shaped , and swing the bail back out of the way so you can remove or install a belt. :D

[Fiddlestix 0]

TT...you have to remove three (all different sizes) total pins vs. one. By pulling the bottom pin only, the hoop will not drop low enough (It strikes the upper quadrant of PTO sheave) to disengage from the triangle cam nor to clear the pilot shaft on PTO sheave assembly. You further need to remove the hitchpin on the actuating link on the triangular cam. This allows the hoop then to angle fore or aft to clear the pulley. Agreed, it appears a mountain out of a molehill. But there are times...

So imagine, if you will this scenario...

Big ol' 48" deck. Weak ol' man (like me!). Gotta slide the deck out sideways to disengage lift arm peg. So this is more easily accomplished in grass... slippery slidey stuff. Lessee... Step one remove the spring bale hitch pin on hoop clevis and PTO pilot shaft. OK that's good. "I'll just lay it here on the foot board". Next, pull the bottom hitch pin to allow hoop to drop below pilot shaft..."I'll just lay it here on the foot board with the hitch pin". Next we remove the hairpin on the PTO actuating arm link (up on top of the triangle cam ). OOooopppss. There went the washers... tinky tinky. On the deck, under the belt guard, in the deep grass, now the actuating trunnion has swiveled around on the shaft and screwed up the adjustment, now while bending around searching for the washers, you put your hand on the footboard so's you can get the bifocals in proper focal range and ..Awww ^&$@&*@ there goes the three hitch pins... somewhere in the grass.

Now that 15 seconds has turned into 15 minutes. "Which way does this trunnion go on this triangular over-center cam... on top or on the bottom?"... "better look over here on my other tractor to see how that trunnion mounts...aww crap. My brother borrowed it to till!" (that is if you are fortunate enough to have a second tractor to pattern off of). "Well, I guess I need to look at the manual... where did I put that?" ... " Now where are those washers??"

Gettin' old is tough!

And all this never occurred with a C series. One large easy (or easier) to keep track of hitch pin. No washers, no adjustments, no frustration.

Not picking fights here, just seeing if there was some reason for this change that I cannot think of! Thanks all. :D

[Don1977 605]

I don't know anything about the newer tractors as I only have a C-series.

It sounds like the old adage " If it ain't broke don't fix it." would fit nicely here.

I believe they fixed some thing that wasn't broke.

[6wheeler 670]

:omg: you are right EZ, getting old does suck. Why can't it just be simple,I think its a conspiracy specifically aimed at older bi-focal wearing folks. (young 20something engineer), "I got an IDEA, lets make extra parts, put em on here and watch these old dudes try to change stuff :hilarious:". Or maybe, you are supposed to call your local friendly Toro dealer to help you.. He can probably order the parts to convert it though. Anyway, what were we talking about? Did you see my glasses? I gotta go try to put my deck back on the 165, If I can remember where I put the darn thing. Have fun...

[W9JAB 156]

:omg:

[chdinct 28]

I don't have a dog in this fight - my 520 has the "new" PTO set up and my 1967 uses something completely different, BUT, I would love to see pic's of Fiddlestix two set ups side-by-side, or someone else's. I can't quite figure out the difference from the descriptions. If I understood it better, I might opt for a conversion, though I don't find the 3-pin routing too bad.

[TT-(Moderator) 1,169]

TT...you have to remove three (all different sizes) total pins vs. one.

Both of my 416 tractors (1990-H & 1992-8) require only the removal of the pin through the bail / stub-shaft on the PTO and the hairpin clip on the trunnion (which is installed up through on both tractors due to the proximity of the muffler) of the engagement rod.

Once the rod is unhooked, the three-hole triangular plate can be swiveled so the bail moves away from the stub shaft, allowing it to swing back past.

I had several mid-80's tractors with the "easier" one-pin bail and couldn't figure out why it was changed. I guess I just got used to the "improved" version.

[rickv1957 77]

All styles are easy compared to most other brands,Rick

[Jim_M 179]

I have a 95 416-H and a 95 520-H and only need to remove 2 pins. I have owned several tractors newer than 88 and can't recall ever having to remove more than 2 pins to change a belt.

[wh500special 2,359]

I've never pulled more than 2 pins either, so I'm missing something too. Granted, routing the tiller belt around the PTO bail seems to take a bit more effort, but it seems like all it takes is one pin from the end of the shaft and a second at the adjustment/engagement trunnion.

What's your manual show to do?

Steve

[Fiddlestix 0]

What's your manual show to do?

Steve

Ahh...yes. You are all correct and I stand rectified! Sort of...

You CAN get by with just 2 pins pulled, the trunnion and clevis hitch pin.

I was relying on the 520H owner's manual which indeed calls for the removal of all three pins! I know not why they specify to remove all three, but that's the official procedure. I have no other owners manuals for the subject models but I would have to ask those that remove 2 pins...

"What's your manual say?" :omg:

[Kelly 1,035]

"What's your manual say?"

Mine don't say anything you have to read it :omg:

[pond195520032003 27]

"What's your manual say?"

Mine don't say anything you have to read it

:D

[chdinct 28]

What's your manual show to do?

Steve

Ahh...yes. You are all correct and I stand rectified! Sort of...

You CAN get by with just 2 pins pulled, the trunnion and clevis hitch pin.

I was relying on the 520H owner's manual which indeed calls for the removal of all three pins! I know not why they specify to remove all three, but that's the official procedure. I have no other owners manuals for the subject models but I would have to ask those that remove 2 pins...

"What's your manual say?"

On my 87 312-8, I only had to remove 2 pins, but on my 520, all three. I've tried removing just two, clevis and trunnion pins, but without removing the pin at the bottom of the hoop, the hoop won't drop out of the bracket the trunnion mounts to. I haven't tried the two pin approach in a while, so maybe I'll give it another go. Just in the habit of doing all 3 now.

[Fiddlestix 0]

...BUT, I would love to see pic's of Fiddlestix two set ups side-by-side, or someone else's. I can't quite figure out the difference from the descriptions. ...

Since you already know about the post '87 style, here are some pics of the earlier stuff Chris...

A typical parts breakdown from a 1987 tractor that illustrates the availablilty and interchangeability of the two types...

(old type encircled in Blue , new style encircled in red)

Now here are some pics showing an old pre-'87 hoop (rod housing as Toro WH calls it) and swinging clevis installed on a 1991 520H...

Pull main hitchpin and swing clevis outward/downward until clear of PTO shaft...

Now swing rod housing and clevis assembly to allow belt removal (or even minor PTO service)...

Of course, if using the mid-mount pulley/sheave for some rear attachment, one side of belt will need to be on the aft side of rod housing inwhich case you may or may not need to remove the remaining pins. If belt is free and with adequate slack, you can remove top trunnion pin and tilt out the hoop and feed the belt arouns in that manner. If no slack available, you will need to remove the lower pin as well and remove the rod housing altogether.

One will note however, that the post-'87 design requiring at least the upper trunnion pin (in addition to the main hitchpin) removal, also correlates to the WH designs with the muffler mounted directly above and sometimes in close proximity of (as in the 520H pic'd above) to the PTO area and that trunnion pin. Be careful grabbing that pin with hot engine and big hands! That also goes for installation especially if you (as I have done) installed washers on the trunnion to keep down vibration noise and wear... now we need one hand to hold trunnion in place while the other slides that washer(s) in there next to the muffler.... Aww you get the picture!

As I mentioned prior and Rick also states, either method is still far superior to other makes. At least you have some option! This series of pics is just to show those like Chris what the subject is. That's all, nothing more, nothing less. :omg:

[Save Old Iron 1,573]

Ahh...yes. You are all correct and I stand rectified! Sort of...

Hallelujah brothers and sisters -

Can I get an Amen to the rectification of the congregation.