Komatsu D41a-3 Brake pedals

[ArtCournoyer]

I have a Komatsu D31A-3 SN 6713 the machine turns perfect with the steer handles however when the brake pedals , right or left are depressed the machine continues to track forward, pushed hard enough it will stall the machine. Base on this stalling I believe the brake linings are I have also checked the adjustments for the brakes and they are within the recomended setting. My question is. Are the foot brakes supposed to stop or turn the machine without pulling the steer handle since the only way the drive is suspended on either side to allow turning is to pull a steer handle. without the drive being interrupted on the side you are braking the machine wants to drive forward fighting or opposing the braking action. What am I not seeing in the linkage or not understanding here?

 

[ps66x4]

I have the same machine.Do your pedals release when you remove your foot? Last time I used mine the pedal spring broke.

 

[ps66x4]

I see you are 30 miles from me.

 

[Welder Dave]

Sounds like an issue with the steering clutches. You should be able to engage both steering clutches and bring the machine to a stop on level ground. I'm not sure if the hand levers control the steering clutches. Older dozers used separate levers for steering clutches and pedals for brakes but I'd think your dozer is much more modern and doesn't use seperate controls.

 

[ArtCournoyer]

To ps66x44 I am in East Brookfield, Ma. and yes, my pedals return fine.
To Welder Dave The hand controls are connected to the steering clutches. The foot pedals are connected to the brakes, but I see no connection to the steer valve from the foot pedals. That is my question. I am trying to sell the machine and I had a person interested in the machine but insisted that the foot brakes should turn the machine. I don't see how that is possible without a connection to the steer valve in order to release that side from the drive train. are the foot pedals in this case specifically for stopping the machine or do they have a function for steering. The machine turns great with the hand levers.

 

[Welder Dave]

The guy looking may have been thinking of a different brand like Cat that steers with just the pedals. Does your machine stop with both levers pulled half way? That would indicate the steering clutches are working. Maybe a Komatsu dealer could tell you if the pedals are supposed to also operate the steering clutches.

 

[coalrulz]

Description from D41A-3 Operation & Maintenance Manual

 

[Welder Dave]

So the pedals are basically a power boost for the brakes or kind of like emergency brakes in a panic situation. It sounds like the OP's machine is working as designed.

 

[ArtCournoyer]

Thank You Welder Dave. This is what I thought but could not find it written anywhere. Thank you for this. where did you find this description of the proper use?

 

[ArtCournoyer]

Im sorry. I also want to thank coalrulz for the book page explaining the operation.