Mower keeps slowing down while mowing

[Copper116 63]

I just got my 79 C101 back up and running... I adjusted everything like instructed in the manual.  The clutch plate is in good shape, belts are ok... pullies are greased and free.  The belt tension is tight to.   I'll be mowing grass and when I get into anything close to thick or heavy grass, the blades slow down and when I clear the thicker areas.. it sounds likes the mower deck speeds back up.  I look back and see the grass is cut sparcely....  I double checked my tensions and clearances and everything checks out... (I believe anyway)   Any ideas what is wrong or what I may try to get this thing cutting right?  thanks in advance!!  

[Stormin 9,981]

Drive belt could be slipping if the grass is too long and thick. Do the engine revs die down? If not you've got belt slip. Try a lower gear when you get to the thick stuff. I run 3rd low mainly but when doing long, heavy stuff I go down a gear.

[Dirtdog524 61]

I suggest that you recheck the clutch plate adjustment on PTO. it would appear that it is slipping somewhat on you

 

[oldlineman 1,481]

That is what I would say is happening

[daveoman1966 3,745]

Are the BLADES tightened properly on the spindles.  If they are not TIGHT, they will spin on the shaft...causing shaft damage in the end.   OR...  do you have the 3 blades on UPSIDE-DOWN...  ???

Not sure what the torque specs are....

Edited May 7, 2020 by daveoman1966

[Stormin 9,981]

14 minutes ago, Dirtdog524 said:

I suggest that you recheck the clutch plate adjustment on PTO. it would appear that it is slipping somewhat on you

 

 

I should have thought about that myself. I had to adjust the PTO clutch on my C-125 last week. If it's slipping, it'll be warm or hottish.

[Ed Kennell 38,028]

Are all three blades slowing down or just the two outside blades?  Could be a problem with the deck belt tensioner.

[troutbum70 857]

I do not have the knowledge of many of the others here, but when mine starts doing the same thing you are describing its because the bearings in the pto hub are getting dry for lubrication. You might try pulling the hub and put a thin layer of grease on the bearings, not a lot just a thin film. You don't want so much it gets out on the disk.

[Copper116 63]

I have the belt pretty tight.  The belt does show some wear but nothing serious.  I have the clutch gap set to around 1/16" +/- as shown in the manual.  The bell does feel hot to the touch tho.  I may try to decrease the gap a bit and see if that helps.   The blades are on there pretty tight.  I do not torque them but using a large wrench and then blocking the blades, I hit the wrench with a large mallet to get them really tight.  I use an air impact to get them off.    The blades are sharp and on correctly.   I thought I had everything set correct... but pulling the bell and checking the bearings is something I'll have to check.  I'll set the gap a bit closer and see if that helps.  What do you guys use to get the 1/16" gap accurate?   What do you guys use as a guage to get the 1/16" gap?   It sucks when you put all your spare time and money into a project, do it right and it still doesn't perform correctly... really boggles the mind.  I did just receive new ag tires from Carlisle for this tractor... and I'm eager to get them mounted.  THANKS GUYS !!! 

Edited May 8, 2020 by Copper116

[Ed Kennell 38,028]

Actually the PTO needle bearing is not rotating when the PTO is engaged.   The only bearing that is turning is the small thrust bearing that is engaging the PTO and I believe it is a sealed bearing.    Are you adjusting the gap on the clutch face or the gap on the clutch brake?    

[oldlineman 1,481]

I personally adjust the PTO by feel but I have owned Wheel Horse since 1979 also a C-101 so have some history with what it should feel like,. It should toggle over and snap into place when engaged, and not get hot while in use.

Edited May 8, 2020 by oldlineman

[Ed Kennell 38,028]

                                               The only time I set a PTO clutch gap is on the old Raider style lever that has a gap calibration notch on the bracket.    With the later style on the C series, I also just shorten the rod by turning the trunnion back until I get enough pressure on the clutch plate to prevent slippage.

 

Raider style lever in gap calibration notch

 

[lynnmor 7,302]

I looked up that 1/16" gap specification, doesn't make sense.  The owners manual calls for the usual .012" PTO brake clearance, so how can you have both?  Just disregard the 1/16" and adjust till you have a firm clamping of the clutch.

[Copper116 63]

I gapped both the brake and the pto clutch disc... then turned the trunnion a bit to.  I played around with it again this morning and low and behold... it's cutting grass pretty good now... tho I'm out of taller grasses to really give it a test.  With your suggestions and advice... it's doing pretty good... and I think we've got it.  I appreciate all your help guys.... thanks a lot.  Now to get my new ag tires put on the back.... and I'll be a happy camper.... 

[oldlineman 1,481]

You can check the clutch bell by hand to see how hot it is,should not be hot at all maybe warm from motor heat that will tell you if it is slipping. Be careful though don't get burnt. You should also smell it if it is slipping.

Edited May 8, 2020 by oldlineman

[Copper116 63]

I believe I got it right this time... just a little more adjustment is all it took... thanks.