out of ideas

[skeptichorse 25]

ok so I finally got far enough along on the deck that I wanted to mount it and give it a try.  I mounted it and hit the PTO and the PTO engaged... and nothing the belt didnt bite.  So I adjusted the tension on the mule drive to the point it stopped the pulley, and the belt never moved once.  So after sitting for 8 yrs I assumed it was hardened and glazed so I bought a new one and even with a new belt it was the same. 

I read that there could be some oil contamination on the clutch causing it to slip, so I sprayed some brake parts clean in the gap between the clutch and the fly wheel, thinking it would clean it out..
When that didnt work.

I adjusted the trunnion and move it towards the back of the tractor one turn.  That seemed to make it worse, now when I engaged the PTO it stalls the motor.  So I turned it ahead one turn back to where it was and still stalls the motor.  So I turned it ahead one more turn, and still stalls the motor with the belt on or off.

Then with the belt off I manually moved the gov to full RPMS then engaged the PTO and it still killed the motor

Now with the belt off just the slightest movement of the pto lever and it acts like a kill switch, You just touch it and it starts to bog the motor.  `

I looked in there as best as I could to see if there was a wire touching the PTO lever thinking that it may be a coincidence and not seeing anything. 

Either the motor isnt strong enough to run the PTO, or there is something in the PTO that is binding it when engaged... even though I can move it freeley by hand.

Before I pull the clutch/pulley assembly tomorrow any ideas?

Thank you

[gwest_ca-(File Mod) 11,479]

When the pto is applied there must be an operator in to seat which closes a safety switch or opens a safety switch depending on the ignition system to allow the engine to run.

The pto clutch lever should snap down over center with some authority when it is adjusted to a point where it won't slip under load.

Garry

[rmaynard 16,297]

Why don't you begin by telling us what tractor it is that you are having problems with.

[daveoman1966 3,839]

On many many model tractors, there is a 'KILL' switch on the PTO lever.  It is in series with other safety switches and this MAY be the problem.  I don't think it is a mechanical issue but, rather, an electrical interrupt or KILL switch. 
Some tractors have 3 switches...seat safety, PTO kill, and clutch / brake  pedal switch. 
As someone else stated....tell us what tractor you are using.

[skeptichorse 25]

Sorry that might help,( I knew what I was refering to though lol)  it is a C-141, I think that the kill switch may have been disconnected I am not positive of that. 

This machine was a barn find that had been sitting outside for the past 8 yrs.

OK so to double verify what was happening I just went down and checked it again.  With the seat switch down, I used my thumb to hold it down (to make sure that it was being fulled depressed) with the machine at full throttle in neutral with the deck up, and the PTO belt off, as soon as I got about 1/3 of the way on the PTO lever the motor started to bog down, and the PTO pulley did start to spin.

I appears that as soon as the clutch starts to make contact on the fly wheel that it bogs down the motor.

The weird part is that prior to attaching the deck, I would drive the tractor around and engage the PTO to make sure it worked and no issue what so ever.  The problem seemed to have started today when I added load to it. 

I also noticed that the clutch doesnt spring back up like it used to, it seems to stick at the bottom, not sure if it is a coincidence or connected to this problem.

[WNYPCRepair 1,923]

You have checked to be sure the blades will turn, I assume?
 

[953 nut 59,968]

Are you sure that when the clutch tightening mechanism was reinstalled the bearing at the end of the clutch isn't in a bind?

[skeptichorse 25]

I can turn the blades with the expected amount of resistance by hand... I can turn the PTO pulley freely by hand, and the mule drive pulleys. 

And all the testing I have been doing After adjusting the trunnion is with the PTO belt off.  So there is zero resistance on the pulley when the PTO is engaged, and it still appears to be adding significant drag to the motor.  You can hear it wind right down, it isnt a immediate kill, but as you move the lever forward you can hear the motor bog, and the longer you hold it maybe 10-20 secs it will stall out, then as you start to let off, it comes right back. 

so I am thinking I have eliminated the electrical issue.

The motor is still a possible, however when I was putting it back in the barn I went through all the gears, and from a dead stop, in 3 hi I dumped the clutch and it was off like a shot. in the barn that was pretty scarey because that back wall came up on me pretty fast lol.  If it was a weak motor under load i would assume it would have bogged vs taking off.

953 Nutt I am assuming you are referring to the Trunnion correct me if I am wrong.  that is just a post that drops down into a hole, so no way to really bind it. 
 

[AMC RULES 37,196]

Can you make a short video of whats going on...
and post it here?    

[gwest_ca-(File Mod) 11,479]

It is easy to rule out an ignition problem.
Connect a test light or voltmeter to the ignition coil (+) terminal and see is you have a constant power supply with the pto off and on.

Garry

[squonk 43,809]

I'm betting something is shutting the engine down as opposed to something binding.

[ericj 1,579]

I'm betting something is shutting the engine down as opposed to something binding.

i agree sounds electrical not mechanical. as soon as you engage the pto it will shut off the engine if the seat switch is not positioned right with either a rider or faulty switch i'd start with the seat switch and then go to the pto switch, if you have not already have done so down load a wiring diagram and use it as your guide




eric j   

[skeptichorse 25]

so back to thinking it is electrical.... even though it never cut out when driving around with the pto engaged now it seems to be shorting out someplace...  I went down to get a video to post here and my camera phone is not cooperating on the transfer of the video only getting a sound bite not the full video.  So while I am working on that....

I unhooked the trunnion and spring, and the motor wouldnt even start...

So I hooked everything back up and it started.  Once I had it running I disconnected them again. and made sure they were clear of the PTO and touched the lever and as soon as it started to move it died out again.  I used a screw driver to engage the pto with the lever disconnected and the motor didnt die out.  so I moved the lever again with it disconnected and it died out.  With out removing the seat pan or anything I traced the wires as best as I could,  It appears that there is a black wire for the seat switch that has been cut and taped off.  and a red wire that goes up to the solenoid.  I disconnected the red wire that appears to go from the seat switch up to the solenoid and the motor wouldnt start.  Reconnected that and it started. 

Is there a way I can unplug the safety switch to test it to see if that is really the issue?  I know on the newer ones you can, I unplug the reverse one because I mow in reverse and my kids are old enough and I am smart enough not to run them over when mowing in reverse. 

 

[gwest_ca-(File Mod) 11,479]

Here are some wiring diagrams that should help. Each circuit has it's own wiring highlighted.
http://www.wheelhorseforum.com/files/file/1971-tractor-1979-c-series-kohler-powered-wiring/

There are 2 pto switches.
One controls the starter circuit. Pto must be OFF for the starter to work.
The other controls the ignition.

When the pto is OFF the pto switch powers the ignition.
When the pto is ON the seat switch powers the ignition if there is an operator in the seat. (Seat switch closed).

Garry

[skeptichorse 25]

ok so it was def electrical.  why it worked last month and not this month is a mystery to me.  So I printed out the wiring guide (thanks for that Garry) and I couldn't find where the short was...so I ran a jumper between the two black wires to bypass the cut off switch. I will figure out a permanent fix later.

Then it took three full turns of the trunnion, to get the clutch to bite. Now the clutch is spinning and not killing the motor.  Now the dumb question, I know but here goes.  What pulley does the belt go on, I assumed the outter most or smallest pulley.  But when I put it on there the belt wont grip. 

When I read the rotary mower manual for the install instructions it reads " place belt on the inside groove of the pto clutch pulley.
If I do that the belt grips and the blades spin but at a snails pace.... maybe it is fast enough but doesn't seem like it would be.

 

[WNYPCRepair 1,923]

It goes on the inner pulley. 

[skeptichorse 25]

ok so my son must have the lucky touch...
I went down and it was set on the smallest pulley, the outter most.  I started the tractor engaged the pulley and nothing.  My son walks to the front of the machine and turns the tensioner twice and the belts grip and it takes off at a high rate of speed that you would expect for a mowing deck.  Vs the inner most one where it spins but not fast enough to cut grass.

So tomorrow will be the first test run to see if it will actually mow. 
 

[gwest_ca-(File Mod) 11,479]

If you are not getting the speed out of the inner pto groove the belt is slipping - not tight enough.
Since the drive is working harder when it is spinning faster the belt needs to be tighter than it does when it is in the outer groove.

The pulley circumference is roughly 3 times the pulley diameter.
Say the outer pulley is 3" diameter so one turn will advance the belt 9".
If the inner pulley is 4" diameter (1/3 larger) that same one turn will advance the belt 12" (1/3 faster)

Garry

[Pollack Pete 2,273]

So.......if the manual and everyone else here says inner groove,which in fact is correct,why are you running the belt on the outer groove???

[skeptichorse 25]

I assumed outter pulley would be faster... smaller puller higher revs/ larger pulley more torque slower revs... but last night was just a test...to get it working.

so I will move it to the inner pulley today, adjust the tension and see what it does.

As always thank you guys for all the great info, and quick responses. 

I will let you know how I make out

 

[bmsgaffer 2,053]

I assumed outter pulley would be faster... smaller puller higher revs/ larger pulley more torque slower revs... but last night was just a test...to get it working.

Your theory would be correct looking at it from the perspective of the deck pulley (device being powered), but from the engine side bigger will turn the blades faster (as Garry @gwest_ca was saying). The inside groove should be faster, if its not look at belt tension like mentioned before.

Also the outside pulley will not be inline with the mule drive and you will wear out your belts faster

Good luck!

 

[MalMac 1,332]

Two things also to check, one that motor is on a shaker plate, when you engage the PTO it pulls the engine to the rear of the tracto. On my C 141 I had it lost ground when PTO was engaged thus causeing all kinds of problems. Ran fine as long as i did not engage the PTO. Second if you are on all the right pulleys and you still can't get belt tight enough maybe you have the wrong belt size on the PTO to Deck.

[skeptichorse 25]

ok so update:  the inner larger pulley was rusty so I engaged the  pto and held some sand paper on it and sanded all the rust off it made it smooth and down to bare metal.  Then I reattached the belt. 
I mounted the belt to the inner pulley, still nothing, so I adjusted the trunnion again, another two turns before it finally stopped slipping when under tension.
Once it stopped slipping I adjusted the tension until the blades came up to speed, and mowed with it. 
It is working but I think it still needs some tweaking, the blades bog down and almost stop in taller grass.  Grass that the cub mows right through so minor tweaking.

Think I am finally on track now, I think the belt is not right, I brought it down to get a new one and they gave me a 1/2 x 95 and it appears that it should be a 12 x 96.6

 

[gwest_ca-(File Mod) 11,479]

Let's verify you are using/getting the correct belt. Some parts lists are notorious for reveling the wrong information.

Width of cut 36", 37", 42" or 48"?
How many blades?
Side or rear discharge?

Garry

[skeptichorse 25]

It is a 42" RD  3 blade set up. 

I ran it for a while then let it sit,  then ran it some more, and each time it seems to cut a little better. 

Until the last time, when the bolt fell of the idler pulley tensioner  which those types of things I expected.  Unfortunately the spacer that sits inside the tensioner was lost too.