Power Max mower deck loosing power

[Tom tractor]

My 9020, 60 inch deck looses all power in high grass.  It only starts to work after I turn the PTO off and then back on again.  I believe the belt is slipping because the motor doesn’t loose power.  I have the mule drive as tight as it gets.  Do you believe the PTO needs adjusting or the belt is the wrong size?  

Thoughts?

[SimpleOrange]

We need to know the numbers from your belt to determine if it's the right one, should be a "B"

Could have a spindle bearing siezing up, belt could be glazed, air gap on your clutch may need adjusting. lastly maybe the blades need sharpening.

By high grass are we talking lawn or orchard grass, my mower struggles with clusters of rouge alfalfa.

[jlasater]

Last I heard (I asked in another thread) the mower deck on the 9020 uses an HA "A" profile belt, not "B". I put a B on mine and it is VERY hard to get it past the battery and front PTO pulley. The length is 93". Gates Power-Rated belts are the closest aftermarket equivalent to the Simplicity belt as far as durability.

[Richard Wright]

The 60 inch deck on my Sunstar uses an AA belt, meaning that it's double sided. Some of the spindles drive from what would be the back side of the belt. When I got the mower it had a regular A belt of the correct length but wouldn't run and cut right because the back side of an A belt is flat where the AA belt is a sort of diamond cross section. Could the 9020 use a similar belt? Putting the correct belt on the Sunstar made a big difference, particularly in high grass.

[jlasater]

There are no idlers riding on the back side of the PTO belt on the 9020 for the mower deck, so a regular profile belt is what is needed. The spindle drive belt on the deck itself does have an idler, but it is a regular flat idler, not a V-belt idler that has a V profile.

[SimpleOrange]

The mower itself uses an "A" belt to spin the blades while the belt coming from the front clutch is the wider "B" such as that I'm using on my snow thrower.

The Gates Hi-Power II  A90 is the correct belt to drive the three blades, not sure what number the "B" belt from the electric clutch is. I do not have that belt.

I'm using a Kevlar belt for the snow thrower, side by side you can see that the belt used on the clutch side is much wider than the "A" belt.

 

 

 

Edited June 10, 2018 by SimpleOrange

[jlasater]

Color me confused. I too think a B belt looks like it fits best but everything I am reading says an A belt is the correct one. P/N 1657044 and 172420 both show up as A, 1/2", 4L dimension belts. Like I mentioned, it was a major chore to get a B belt past the battery hold-down. I had to roll the belt which I'm sure isn't very good for it.

Further info, when I took the mule drive idler pulleys off to replace them (one of them lost all the bearings), it was obvious the B belt I have been using was only riding on the outer 1/8" or so of the pulley sheaves on one side, but about 1/4" on the other side. I assume that was from differences in tension on the belt sides as it bent 90deg and another 90deg.

Edited June 10, 2018 by jlasater

[SimpleOrange]

Below, the complete electric pto has the wide groove is from a Deutz Allis that uses the B belt, large pulley by itself of from another front PTO from a 9020 that I have as a spare. I've fitted both the A and B belts into each.

I now think the mower deck and my snow thrower if one were to go by the part numbers uses an "A" belt, I've used the B on my snow thrower for the past two years without any problems.

Like jlasater says the B is a bit tight to get past the battery hold down.

First image is the belt that runs the hydraulic pump on the Fel and it looks to be an "A" belt.

 

 

 

[Tom tractor]

I believe the problem with the loss of power is coming from the PTO needing to be adjustmented.  The manual is a bit confusing.  It says to stick a .010 feeler gage 1/16 into the PTO.  MY QUESTION IS..  within the measuring hole ... is that between the actual clutch plates (which I can’t see) or between the outside guard and clutch housing (where the arrow is pointing - which is now about 1/8 of an inch wide.)

Edited June 13, 2018 by Tom tractor

[PhanDad]

6 hours ago, Tom tractor said:

 is that between the actual clutch plates (which I can’t see) or between the outside guard and clutch housing

On the adjustable electric clutch I have, you measure between the clutch "plates":

 

 

[PhanDad]

On 6/9/2018 at 11:49 PM, jlasater said:

Color me confused. I too think a B belt looks like it fits best but everything I am reading says an A belt is the correct one. P/N 1657044 and 172420 both show up as A, 1/2", 4L dimension belts.

And to add a bit more confusion, according to the Simplicity Belts cross section table:

A "HA" belt is 1/16" deeper than a standard "A" belt (4L cross section) and a "HB" belt is 1/32" wider and 1/16" deeper than a standard "B" belt.  So a "Simplicity" HB belt would ride even higher in the 9020 pulley shown above.

 

 

[Tom tractor]

Out of curiosity - what would happen if I over tightened the clutch?  Would it cause it to always be engaged?  

[ACT816]

It doesn't look like you are adjusting the actual clutch but the brake plate.  Some had this and some didn't btw.  I discarded it on mine before I did the repower and the new clutch doesn't have this either.  The spacing between the field and the rotor is not adjustable:  Field is 49 and rotor is 50. 

 

[babablacksheep]

Before you tear into the clutch and replace all the belts, check your blades. Bogging down the mower is usually due to not being able to discharge the clippings fast enough.  A AC720 is capable of mowing grass and weeds almost half way up the grill.  Your blades must be sharp, the lift wings on the ends must be in good shape, and the engine should bee at full throttle. If it still bogs, make two passes. Do the first with the deck all the way up, and the second at the finish height you want. Good luck.

 

[PhanDad]

On 6/14/2018 at 8:57 AM, ACT816 said:

It doesn't look like you are adjusting the actual clutch but the brake plate.

I would say I'm kind of adjusting both.  The way the newer clutches (the triangular plated ones are the only ones I've messed with) work, when they are disengaged, the rotating clutch plate of the load pulley moves away from the field plate (up in my pics above) and the "backside" of the  pulley plate contacts the "brake plate as you called it" and stops the load pulley from rotating.  The gap that I tried to show in the pics is the only gap there is since the "backside" of the pulley plate is against the "brake plate".  When you adjust the gap, you are setting the distance between the "front-side" of the pulley plate to the field plate.  The gap gets larger with time since both the "backside" and "front-side" ablative linings wear.  Here's a side view pic of the entire unit to maybe help understanding:

On the older electric clutches like the OEM supplied one on my Homelite T-12, I agree "The spacing between the field and the rotor is not adjustable".  

And it's also interesting to note that he older electric clutches had 1 bearing while the newer ones (as shown above) have 2 as can be seen in the cross section drawing of the pictured clutch: 

Drawing Notes:

On 6/14/2018 at 6:22 AM, Tom tractor said:

Out of curiosity - what would happen if I over tightened the clutch?  Would it cause it to always be engaged?  

If it's like the clutch I described above, and by "over tightened" you mean minimize the gap, I would think the clutch might not disengage when turned off. 

If the gap is totally eliminated, depending on how much spring pressure is applied, you'd have at best a smoking clutch since both sides of the load pulley would be touching and either one of both would be slipping.  Or the anti-rotation "finger" would bend/brake and the whole unit would rotate tearing the connetion wiring. 

  

Edited June 21, 2018 by PhanDad
changed some wording for clarity (hopefully)

[ACT816]

PhanDad,

     I agree with what you see with "new" clutches.  I have a Honda up front now and the clutch has two bearings.  The Onan clutch though, mounts to the front of the engine directly which is a little different than riding on the output of the crank.  I have a "spare" Ox clutch on the shelf that I'm thinking of pulling apart to see if I could mock up.  I'm looking to do this for the rear PTO btw, not the front, since I'm already running what I'll call a modern front clutch. 

    I don't know that another clutch couldn't be installed, it would have to line up with one of the original mounting bolts, through a bracket, plate or ? to prevent it from spinning.  I can't remember if the Onan has the face showing or not where new clutches are mounted against or have a bushing against.  If that makes sense.

     Note that the rear PTO has an additional piece that bolts to the field that does have an additional bearing for support to the shaft.  It seems that the designers thought the hard mounting to the front of the engine made the other bearing not needed.  Would you agree?

 

For your blades issue, you could remove the brake plate to see if that has any impact.  The other suggestions are all likely inputs.  Also, I removed the rock guard (assuming that is what it is) from my deck as it was just collecting clippings and I'm the only one that uses the tractor.

My tractor also had an interesting anomaly. One of the spindles didn't have the center "cup" for grease retention and when I rebuilt my deck, this spindle had more play than the rest.  Not that it was contributing to anything but I'm not sure but I know it wasn't helping with keeping the bearings greased.

 

 

 

[Tom tractor]

Thanks for the replies.  I will tighten the four bolts and see if it helps matters.  I believe the best is the original belt from new.  The deck appears to have extreme little use.  Maybe the belt is causing slipping due to age???

[ACT816]

Just thought I'd see if you were able to figure out what the issue was?

[Tom tractor]

Not yet.  While testing the PTO I ran into a problem.  The motor isn’t starting.  It will crank one or two revolutions while starting but that’s it.  After tying to start it after multiple tries the starter now only clicks.  The suliniod was already tapping and now the starter won’t crank.  I think the Tractor needs a new starter.  Which means pulling the engine.  

****** How tough is it to pull the engine and replace the starter?

Once that is fixed I believe the Tractor needs a new belt to make the deck work properly.  

[lugnard]

You didn't by chance leave the pto switch engaged and are now trying to start the motor??? I can't even believe I am telling this story but I was mowing with an un-named mower..(craftsman..yikes) and my wife wanted to ask me something so I shut off the tractor. Went to start it and no go... I started ripping into the starter, solenoid, battery, and cussing it to no end when I finally realized the pto was still engaged. took awhile tho........

Harry

 

[BLT]

What about the auto tensioner on the mower deck, is that free and keeping belt tight?

Look at this video. You have same basic arrangement.

https://www.youtube.com/watch?v=8xgbeEI9NiQ

[Tom tractor]

On my 9020 I am using the Gates Hi-Power II  A90 sold by Napa (non Kevlar) belt and it is slipping off the auto tensioner wheel while mowing (60 inch deck).  Everything works well until the belt jumps after the deck is uneven on the ground while mowing or if the deck is lowered while mowing. The belt also gets very hot while mowing. Any idea what is causing the belt jumping off the auto tensioner wheel? Could the belt be slipping or the auto tentioner not adjusted right?

[BLT]

3 hours ago, Tom tractor said:

On my 9020 I am using the Gates Hi-Power II  A90 sold by Napa (non Kevlar) belt and it is slipping off the auto tensioner wheel while mowing (60 inch deck).  Everything works well until the belt jumps after the deck is uneven on the ground while mowing or if the deck is lowered while mowing. The belt also gets very hot while mowing. Any idea what is causing the belt jumping off the auto tensioner wheel? Could the belt be slipping or the auto tentioner not adjusted right?

More then likely your auto tensioner pivot arm bushing (29) is rusting to the bolt(30) not allowing the arm(28) to stay active. The operator's book does a lousy job of not mentioning why it should be lubricated. That arm is highly active engaged. It needs a few drops of oil at least every other year. Watch this and forget color. 

[Josiah deshong]

I had to physically bend my deck with a big hammer to get my idler pulley to run true and keep hold of the belt. No matter what I did my idler was either rubbing the belt cover or throwing the belt so I  beat banged and bent till it ran square with the blade pulleys it’s worked right all summer now. Also my deck was bogging down recently and it turned out one of the cables came unhooked I hooked it back up and it’s fixed probably not ur problem though