Fleming topper shearbolts

[Six Dogs]

Ok so I’m a sheep farmer so bear with me,just bought a new 9foot Fleming topper but everytime the pto is engaged on tick over on our Valmet 6400 it blows shearbolts!
The dealer has tried it on one of their tractors and it’s fine,so a bit stuck.....
Help please!
Thanks in advance

 

[bobk]

Is it in the air when you kick it up ?

 

[Six Dogs]

Yes tried it level

 

[PuG]

On the Fleming site they have two versions of the 9ft model, standard one is rated for 55hp at the gearbox and the HD is 70hp (not that it should matter). What size is the shear bolt and rating? Done up tight? Is your Valmet reasonably abrupt on the pto? I assume its free to move by hand?

 

[Six Dogs]

It’s a 10.9 shearbolts,it’s the HD model which I saw them demo on a 250 hp NH,I’ve no comparison if ours is abrupt on pto
Yes the topper rotors spin easily by hand

 

[Hesstondriver]

have you tried 'bouncing the pto in to gear'

by that I mean just flick the switch in and straight back out again, then back in once the rotors have started turning.

maybe some one could explain that better than me !

also a call to tractor dealer to see if the pto is supposed to have a 'soft start on' it

 

[Six Dogs]

Apparently the tractor doesn’t have a soft start but it’s been suggested that the solenoid could be changed?

 

[Paddington]

Are the shear bolts catching the UJ ? Went through several one day until I turned the PTO by hand and realised the spare bolts the dealer had supplied were too long !

 

[Six Dogs]

Are the shear bolts catching the UJ ? Went through several one day until I turned the PTO by hand and realised the spare bolts the dealer had supplied were too long !

Didn’t notice that when I tried turning it by hand

 

[Mur Huwcun]

Common problem with toppers, as they have a flywheel effect rotation it takes a bit of power (similar to 2 drum mowers) to start off but they also need a lightweight safety protection device incase of blade impact due to the light Comer built gearboxes (it all comes down to cost). Tractors without soft start really do struggle and the problem gets worse by using economy PTO (light work, safe fuel etc).

Unfortunately you will have to feather the PTO in everytime by either flicking the switch on and off a few times or trying to engage the PTO same tine as taking off as that will labour the engine slightly. Blue tractors are quite harsh on startups aswell. Remember going through loads of shearbolts once with a group of students as they were letting the clutch out to harsh at the ends of fields or when reversing into corners and the engine speed surge was enough to pop the shearbolt!

Maybe an 8.8 bolt would be better than a 10.9 as it will be slightly softer and won’t shear so quick, incidentally self coloured bolts make much better shear bolts than zinc coated once. Don’t be tempted to re drill for a larger size or weld it up or your gearboxes or donut couplings will be next to go.

 

[james ds]

Adjust down the idle Rev on the 6400 , if it's the older model you can pull the stopper a bit to cut revs. This should work.

 

[Dave W]

have you tried 'bouncing the pto in to gear'

by that I mean just flick the switch in and straight back out again, then back in once the rotors have started turning.

maybe some one could explain that better than me !

also a call to tractor dealer to see if the pto is supposed to have a 'soft start on' it

This. It's the startup on the pto that's too sharp. Used to do the same on a major 3 deck roller mower we had.
Had to flick it on-off-on-off till the blades got some speed up. Never did a shear bolt once running

 

[Moors Lad]

Once had a batch of "cr*p" shear bolts (from a local independant man) - they caused me to swear a fair bit - changed bolt supply and problem solved!!

 

[tinman]

ive fitted small accumulators to the pto hyd supply line to combat this problem, once you hit the pto switch effectively the the accumulator dose the feathering, it would let you away.

 

[PuG]

ive fitted small accumulators to the pto hyd supply line to combat this problem, once you hit the pto switch effectively the the accumulator dose the feathering, it would let you away.

I was wondering about our Duetz Agrotron 165 mrk3 - I don't know if it has soft start or an accumulator already (the manual is unreadable!) but I was thinking of trying to fit something for our drum mowers, aggressive starting. No problems yet. What accumulators did you fit?

 

[Kidds]

Can’t beat land drive to get the blades turning ready for the proper pto being engaged.

 

[Boydvalley]

Got a Fleming side mounted. Have to start at tick over on 540 then restart on 1000 while still turning. Got my bolts from Screwfix on offer £2.70 for a hundred. Seem to break at the appropriate time.

 

[tinman]

I was wondering about our Duetz Agrotron 165 mrk3 - I don't know if it has soft start or an accumulator already (the manual is unreadable!) but I was thinking of trying to fit something for our drum mowers, aggressive starting. No problems yet. What accumulators did you fit?

just the one on the supply line, Teed it off to the accumulator, roundabouts between .15 and .2 of a ltr, i can charge them myself so i set the pressure in a working environment.

 

[AFM]

Could put a slip clutch on to solve it more expense but could be less than repairing tractor/buying another topper!

 

[Bury the Trash]

theres a whole ' waste of money ' industry built around toppers