Bobcat 435 brakes at high speed

[abaco]

Hello,
While traveling in low speed when I engage the high speed button on my control arm, the machine speeds up and with in a few seconds the machine stops as if brakes go on. I have to push the speed button again to resume in low, has anyone had the problem and is there a simple way to fix?

 

[Ryanrb25]

is it just one side or both at the exact same time?

 

[abaco]

is it just one side or both at the exact same time?

Thanks for the reply. Both tracks stop at the same time when traveling on even grade, When traveling on a down slope the machine will stay in fast gear only if the travel control sticks are pushed hard in direction of travel.

 

[6.4twins]

We get the same problem when the tracks are full of gravel or dirt and when there's a slight slope.. But we never had that problem on a level ground.

 

[mikebramel]

Sounds like your brake pressure isn't holding. Is the engine at full throttle? Tried changing the filter on that part of the circuit?

 

[abaco]

We get the same problem when the tracks are full of gravel or dirt and when there's a slight slope.. But we never had that problem on a level ground.

Thanks for the reply, seems like my tracks were always full of mud and or ice when problem happened in early spring time. Haven't tried to travel in high speed lately because I was afraid of breaking the machine. I'll clean the tracks and see if problem persists in high speed travel. Thanks again!

 

[Ryanrb25]

it shouldn't stop dead on both sides if it's just dirt and mud....never had this issue with any of our 435's. Have the Final drive oil's been changed recently?

 

[mikebramel]

Sounds like your brake pressure isn't holding. Is the engine at full throttle? Tried changing the filter on that part of the circuit?

Pilot pressure isn't holding at the brakes. Either leaking down into the brakes, insufficient flow from the pump or leaking in the valve

 

[abaco]

We get the same problem when the tracks are full of gravel or dirt and when there's a slight slope.. But we never had that problem on a level ground.

I finally cleaned the tracks and seems like the problem is resolved. Thanks for your help!