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Worst Final Drive Motor Fails: Radial Piston Hydraulic Motor

In our continuing discussion on some of the worst final drive motors fails we’ve seen here at Texas Final Drive, allow us to present a very badly scarred radial piston hydraulic motor. This final drive was totaled -- there is just no coming back from this kind of damage.

Worst Final Drive Fails 2

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Wreck of a Radial Piston Motor

If you take a close look at this image of a failed radial piston motor, you’ll start to notice more than a few disturbing things. Starting with the cam, you can see the surface is very heavily scarred and can’t be restored to usability. You will also notice that some of the radial pistons have come apart, most of them are heavily scarred, and one is even twisted inside the piston housing.

In the next image, which is the same motor, you can see some additional signs of scarring as well as a partially disassembled, jammed radial piston (that we found this way). This is not something anyone expects to see when they open up a radial piston hydraulic motor. There is no way this hydraulic motor was providing much torque at all.


Hydraulic Contamination

This particular damage didn’t happen overnight, and neither did its cause. After carefully studying the damage and the rest of the contents of this hydraulic motor, our technicians determined that the root cause was contamination in the hydraulic fluid. Over time, contamination causes serious wear that can lead to cascade damage of other parts in the hydraulic motor.

Causes of Hydraulic Contamination

In cases like this, the contamination likely made its way inside through a damaged seal or failed hydraulic filters. Most likely the fail sealed was never discovered, and things just got progressively worse within the motor. Based on the condition of the radial pistons, one would suspect that this motor started making some unusual noises and vibrating quite a bit before it failed. If the problem had been caught sooner, then the final drive motor might have survived.


This kind of damage is a good example of why we put so much emphasis on immediately replacing leaking seals. Leaking final drive seals can lead to extreme contamination problems and extensive damage to your final drive motor. And here is another lesson to learn: if your motor is exhibiting poor performance or making strange noises, don’t ignore it -- get it checked out before your drive ends up totaled.

Visit the Final Drive Shop for all of your hydraulic final drive motor needs!

Excessive Noise Troubleshooter Guide for Final Drives CTA

Topics: Final Drive Failure, Hydraulic Contamination, Radial Piston Motor

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