Ferris 400S Deck Drive Belt failure

GetTechnicalWithJd

Well-Known Member
Joined
Jul 28, 2013
Threads
10
Messages
128
Hi All,

Anyone else experiencing premature failure of the deck drive belts on the 400S with Triple deck?
 

mechanic mark

Lawn Pro
Joined
Jul 15, 2013
Threads
175
Messages
7,381
https://www.ferrismowers.com/na/en_us/product-catalog/zero-turn-mowers/400s-zero-turn-mower.html

see pages 8 & 9 idler mount bolts, parts 0100 & 0220, grade 5 bolt 3/8 x 16 that goes through spacers idler arms will fail, sloppy play, wear out belts, idlers, 3/8 bolt will stretch & bend, my son & i made a trip to industrial bearing & purchased grade 8,7/16" bolt 2 & 1/2" long with 1 & 1/2" shank 2 flat washers & a self locking nut to fit bolt. we drilled out spacers to 7/16" as well as deck & bracket, installed bolt with washer through bottom of deck through spacers & idler arms, installed flat washer & self locking nut. i lube with oil when i remove deck for maintenance. most decks have 3/8" grade 5 bolt passing through idlers & it will eventually fail.

https://www.lawnmowerforum.com/showthread.php/20382-Mower-belt-keeps-breaking

this is grade 5 bolt on straight edge, warped 3/8 x 16 idler arm mount bolt, broken upper idler arm & belt
I'm not talking about blade bolts breaking, i'm talking about idler arm mount bolts being too small to handle load when engaging PTO clutch. put your hands on idler arms & check out sloppy play side to side & also up & down. see pages 8 & 9 above & bolts 0100 & 0220.
 
Last edited:

GetTechnicalWithJd

Well-Known Member
Joined
Jul 28, 2013
Threads
10
Messages
128
https://www.ferrismowers.com/na/en_us/product-catalog/zero-turn-mowers/400s-zero-turn-mower.html

see pages 8 & 9 idler mount bolts, parts 0100 & 0220, grade 5 bolt 3/8 x 16 that goes through spacers idler arms will fail, sloppy play, wear out belts, idlers, 3/8 bolt will stretch & bend, my son & i made a trip to industrial bearing & purchased grade 8,7/16" bolt 2 & 1/2" long with 1 & 1/2" shank 2 flat washers & a self locking nut to fit bolt. we drilled out spacers to 7/16" as well as deck & bracket, installed bolt with washer through bottom of deck through spacers & idler arms, installed flat washer & self locking nut. i lube with oil when i remove deck for maintenance. most decks have 3/8" grade 5 bolt passing through idlers & it will eventually fail.

https://www.lawnmowerforum.com/showthread.php/20382-Mower-belt-keeps-breaking

this is grade 5 bolt on straight edge, warped 3/8 x 16 idler arm mount bolt, broken upper idler arm & belt

We haven't had any of the blade bolts fail.

The belts are failing by simply snapping on over 4 machines. Some snap at 6 hour and some at 20 hours. I have one machine at 146 hours on its seventh belt!

And this is in light load condition cutting a soccer pitch.
 

daybris

Forum Newbie
Joined
Jun 19, 2019
Threads
2
Messages
7
hi
my belt snapped twice but i guess i drive really hard.
first time was a little stick and the other time was very wet grass and raining.
i know on other brands here in sweden they sometime change manufactures to cheaper belts with bad quality.
its good to have in mind to that washing the machine with degreaser and stuff may damage the belt wch gets stiff and snaps.
regards from sweden :) and good luck
 

GetTechnicalWithJd

Well-Known Member
Joined
Jul 28, 2013
Threads
10
Messages
128
hi
my belt snapped twice but i guess i drive really hard.
first time was a little stick and the other time was very wet grass and raining.
i know on other brands here in sweden they sometime change manufactures to cheaper belts with bad quality.
its good to have in mind to that washing the machine with degreaser and stuff may damage the belt wch gets stiff and snaps.
regards from sweden :) and good luck

Hi daybris,

Thanks for the input.
I agree regarding the chemicals damaging the belts, but the machines in question have failed before they even got to their first wash!
In my opinion the belt is a bit light for the job.

Greetings from South Africa.
Take care.
 
Top