PTO clutch issue

[saugerstock 8]

Hi Folks,

 

A couple of weeks ago I bought a 314-8 in great shape.  That being said, there is always initial maintenance to take care of, but I did that and it was mowing fine.  Until...

 

I was going to mow today and when I tried to engage the PTO it squealed and bogged the engine down.  Had I engaged it fully, I think the engine would have stalled.  This came out of nowhere.  Four days ago everything was fine.  In the interim, I changed the rear tires and tranny oil, but I don't think that has any bearing on the problem.

 

I removed the mower belt from the PTO pulleys to take the deck out of the equation.  Same issue.

 

Thinking it could be a seized bearing I pulled apart the PTO clutch mechanism.  All the bearings were fine.  Looking online, I read that insufficient clutch facing could cause the issue.  The facing looks OK to me, and measures ± 1/8 inch, but perhaps that is not sufficient.

 

When the engine is running and I look at the clutch movement, it doesn't appear to be rubbing on anything. 

 

I'll bet the solution is something simple!  Thanks for any ideas...

[squonk 46,597]

A worn clutch face won't bog the engine down. Just for the heck of it, check your seat switch. It's designed to shut the engine down if you try to engage the PTO while not in the seat. Sounds like the switch thinks you're not in the seat.

[Handy Don 16,617]

2 minutes ago, squonk said:

Sounds like the switch thinks you're not in the seat.

In your other post, you mentioned moving the seat, so this seems likely to me, too.

PLEASE don’t fix this by trying to circumvent the seat switch. You seem like you have the skills to come up with a clever and safe solution!

On two of our tractors I added seat slides to accommodate the more than 16” height difference between the tallest and shortest operators. The latter are also noticeably less weighty than the former, and when they leaned forward to crank the steering had the engine stop! I switched the switch actuator to a longer plunger with a longer, soft spring and a plunger guide so it works well. 

[8ntruck 8,874]

Take a look at the 'mule drive' - that is the set of pullies at the front of the tractor that the mower drive belt 'bends' around to get from the horizontal crankshaft to the vertical mower deck drive spindle.  Might have a bad bearing there or something jammed up in the pulley housing.

 

One of my tractors is a 1973 14-8.  It is a direct ancestor to your 314-8 - many, many similarities between the two.  Good tractors.  Mine has done everything i've asked of it.

 

While mowing a couple days ago, a corn cob got flipped up into the mule drive and jammed between the 2 pullies. Yup - it stopped the deck and caused a light burning rubber smell before I got everything shut down.

 

Good luck and enjoy your Horse.

 

Good bunch of folks here, too.  I'm almost convinced that this group has broken and repaired just about anything on a Wheel Horse that can be broken and repaired.  We are more than willing to offer advice - sometimes it is actually helpful.

[saugerstock 8]

squonk and Handy Don:

 

Yes, thank you, I will do as you suggested.  It will be interesting if that turns out to be the issue because-

 

When I bought the tractor, there were a few electrical anomalies.  One was that it would only start with the PTO engaged!  I figured that someone had reversed the lockout switch connections.  I checked the schematic and saw that there were two micro-switches involved, one using the NO and the other the NC terminals.  Once I took out the battery and got a good look at the switches it was obvious that one of the plastic housings had been broken and the loose F spade plugged onto the wrong terminal. I dielectric greased everything and put it back together.  Problem solved.

 

Another issue was the seat switch.  It was disconnected and jumpered somewhere down the line.  Normally this wouldn't have bothered me because, on the Troy-Bilt with a hydro drive, once my foot was off the clutch, the tractor stopped.  Like I wrote, I had PTO issues and hated to turn it off and on.  Maybe I was tempting fate, but I mowed in steel-toe boots and always stepped wide of the deck when dismounting to pick up one of the dogs' bones or a branch in my way.

 

But I quickly realized that the Wheel Horse is an actual tractor.  As long as it is in gear and the clutch is engaged, if you fall out of the seat it's going to keep moving.  I know a few people around here who have lost friends and family on farm tractors that way, so I was planning to reconnect the switch.

 

My tractor's seat was falling apart.  I found an aftermarket MTD seat for $30, but it used a different kind of switch.  At first, 'cause I thought it would be more elegant (and I'm cheap), I considered adapting the Wheel Horse switch to the new seat by cutting out the WH mounting area and riveting it over a hole on the new seat.  The center hole wouldn't leave enough space for the switch length, so I thought to cut a hole at the side and mount it there.  But the new seat's foam was too tight and that was just a PITA too far. 

 

So I'm going to buy a switch that fits the seat. When I match to the seat's model #, all the switches that show up are square with a big center plunge button.  Nothing that would fit that circle.  Oh well, guess I'll have to make an adapter plate for that! 

 

But back to your suggestions, today as I was troubleshooting I connected the WH switch to its hanging cable, put it up on the seat, and sat on it while I engaged the PTO.  I've checked the switch and know that it's functioning, but I was less than rigorous in my test because I was "sure" of the outcome.

 

Let me try that again and I will get back to you.

 

 

 

 

 

[saugerstock 8]

One more thought on the seat switch.  I looked at the schematic.  When the operator is not in the seat the circuit opens and it seems like the tractor should shut down instantly.  

 

My problem "feels" more mechanical.  As I push the PTO lever to engage, the engine starts to bog down.  The harder I push, the more it stalls.  

 

 

[953 nut 66,138]

7 hours ago, saugerstock said:

My problem "feels" more mechanical.  As I push the PTO lever to engage, the engine starts to bog down.  The harder I push, the more it stalls.  

If the Trunnion is not aligned correctly the PTO may be binding when you push the lever forward. 

[Handy Don 16,617]

12 hours ago, saugerstock said:

So I'm going to buy a switch that fits the seat.

Both of our tractors had the seat switch mounted in the fender and activated by a spring-loaded plunger attached to the seat. You have the newer (and probably better) style!

My own ’64 has none of the safety switches and hence I”m super cautious (aided by long-practiced muscle memory) when mowing and, so far, have allowed only one person to mow with it. Fall off and it’ll just “mow on."

Edited 3 hours ago by Handy Don

[Bill D 2,861]

10 hours ago, saugerstock said:

One more thought on the seat switch.  I looked at the schematic.  When the operator is not in the seat the circuit opens and it seems like the tractor should shut down instantly.  

 

My problem "feels" more mechanical.  As I push the PTO lever to engage, the engine starts to bog down.  The harder I push, the more it stalls.  

 

 

Sounds like a bad thrust bearing thats seizing under load. If you unhook the clutch hoop, then spin the end piece by hand,  how does it feel?

Edited 2 hours ago by Bill D

[saugerstock 8]

Thank you to everyone who gave me suggestions on this issue,

 

squonk and Handy Don - BINGO!  You were correct, it was the seat switch.  I put a temporary jumper in the connector and everything is working.  New switch is on order. 

 

In the meantime I will be careful while mowing, and not just for my own health.  Thinking about what Handy Don wrote: Fall off and it’ll just “mow on". If that happens and the tractor chews through my wife's plantings, the horse and I will be looking for a new stable!

[saugerstock 8]

54 minutes ago, Bill D said:

Sounds like a bad thrust bearing thats seizing under load. If you unhook the clutch hoop, then spin the end piece by hand,  how does it feel?

I just posted that you were correct - the seat switch.

 

I did check the bearings yesterday and everything seemed fine.

[saugerstock 8]

1 minute ago, saugerstock said:

 

Edited 1 hour ago by saugerstock
double post. i want to delete this one

[Bill D 2,861]

I converted to the early style seat switches in the fender pan, just use the old seat switch assembly to make an adapter. If you cut the wire off the old switch then crimp on two insulated 0.187 female spade terminals it will plug in to the existing harness and connect to an older style seat switch.