A stump jumper is a dish shaped heavy-duty steel plate found on the underside of most quality rotary cutters or “bush hogs”. Some people refer to them as the “blade pan”. The rotary cutter’s blades are affixed to this metal dish, rather than directly to the gearbox spindle.
The purpose of a stump jumper is to encourage your cutting assembly to ride up and over hard obstacles, such as stumps, rather than slamming directly into them.
Where It’s Located
In the case of a single spindle cutter, a stump jumper is located at the center of the underside of the deck, just above the cutting blades.
If you look under a brush hog, it should be obvious as to whether you have a blade pan or not. Look for the thick steel plate that the blades are attached to.
How It Works
When a rotary cutter’s blades encounter a hard object, such as a stump, the blades swing away upon impact, and it’s the stump jumper that absorbs the majority of the impact.
The pan of the stump jumper helps to lift the cutting mechanism above the stationary object. This lifting helps to prevent damage to the blades, but more importantly to the gearbox and drivetrain.
Advantages Of A Stump Jumper
1. Implement Longevity
They increase the longevity of a rotary cutter, especially if you’re regularly taking it into unfamiliar territory, where hidden obstacles may be lurking.
2. Speed Of Cutting
Knowing you have the protection of a stump jumper allows you to mow a little faster than you would otherwise in unfamiliar areas.
3. Repair Cost Savings
They add protection to your blades, gearbox and frame, thus reducing the need for future costly repairs to your implement, and possibly your tractor.
Replacements Are Expensive
Whenever possible, I try to minimize slamming my rotary cutter into stumps and rocks, because a replacement stump jumper is surprisingly expensive and a real pain to replace.
Maintaining And Inspecting
Simply have a look under your brush hog regularly to ensure your blades and pan are in good working condition. Check for cracks, or deformation that you might need to address. A stump jumper is typically a replaceable but expensive part.
Good Modern Brands Have Stump Jumpers
Most any quality brush cutter, such as Land Pride, is equipped with a stump jumper these days. Some will be round, and some will be oval shaped, but both are fine.
Round vs Oval Stump Jumpers
The simple design of a round stump jumper makes it a bit more durable than an oval shaped pan.
Supposedly the biggest advantage of an oval blade pan is that it has reduced drag when moving through dense vegetation. However, some people believe the oval design actually results in the oblong shaped pan slamming harder into obstacles, thus resulting in more damage, more frequently.
If I had the choice, I would stick with the more durable round design, but I wouldn’t let pan shape sway me to one brand over another. Essentially, it probably doesn’t matter much which design you get.
Conclusion
A stump jumper is an extremely important feature found on quality rotary cutters. I personally would not purchase a bush hog that didn’t have one.
The protection that a blade pan provides makes them well worth any added expense on the front end. Their ability to absorb unexpected and sudden impacts will certainly save you some headache and expense from potentially costly repairs.
Augustus Clay
