Sunday, November 4, 2012

Restoring a Gardner Denver Mining Mucker


What is a mucker?
Muckers were used underground to remove rock and ore known as “Muck” after blasting in the tunnels. They were used from the 1930’s through the 1960’s and still in some small operating mines. The mucker weighs 4,300 pounds and operates on 60 to 100 pound air, no more than medium sized drifters. There are two air motors that run the mucker, a drive motor and dipper motor. The drive motor is located under the base and drives the four wheels to move the mucker back and forth. The dipper motor operates the shovel on the front of the mucker. It picks up the muck and flings it over the machine to an ore cart that is attached to the mucker. When the ore cart is filled, it is detached and taken to the surface and dumped.   The drawing below shows a side view of the mucker with the air motors.

The picture below shows a GD-9 mucker in operation on the cover of a tech manual for the mucker. You can see the ore cart behind the mucker. The dipper is full and ready to fling the material over the Muckers into the ore cart. 

Where did this Mucker come From?
The Gardener Denver GD-9 mucker that we restored was used in the Red Rover Mine in Seven Springs, Arizona. The Red Rover Mine was established around 1882 and was the most successful mining operation in the Cave Creek Mining District.  Copper carbonates, that contained as much as 2000 oz. of silver per ton, were found at the surface of the deposit. Major production at the mine occurred from 1882 to 1917 during which $200,000 in copper and silver was recovered, but between 1917 and 1953, it had been operated intermittently.
The mine was purchased by the Tozier Family in the early 1960’s. By the late 1960s they had found the money to do some under-ground mining.  A new drift/tunnel was dug into the hill under an old building which had been the Cook Shack. As the drift was dug, water and air was piped in and track was put down for the ore car and mucker.   Two family members ran the operation.  They would drill and shoot the rock face and then move the waste outside with the mucker and ore car.  They always moved carefully when the mucker was running.  The heavy steel shovel would jerk up and back to load the ore car.  It could have easily broken an arm or someone’s head if one got in the way. We visited the mine to see about some timbers to be used on a stamp mill restoration and that is when the two Muckers and ore cart were obtained.

How Did We get it from the Mine?
The mucker was acquired in March of 1996 from the Tozier family at the Red Rover Mine. The mine is located off the Seven Springs road, about 5 miles south of the springs. The access road is located on a dirt road that is about 2 miles long. About half of the road is actually a dry wash with large rocks that are shifted around when the rains hit. It is not your ideal road to bring the 4,300 pound mucker out in the back of a pickup truck. We did have about 15 volunteers to help in getting the mucker and some other items that had been acquired from the Toziers. We had no jacks or other devices to raise the mucker off the ground. Everything was done with levers and cribbing timbers. The pictures below show the various stages of the transfer of the mucker into the truck bed:

We moved the mucker out to a location near the truck.

We jacked the mucker off the ground about 3 feet with nothing but levers, cribbing timbers and brute strength.

We dug holes to back the truck into and then rolled the mucker onto the truck bed.

Restoration of the Mucker
The mucker was totally restored back to operation. This was done in several steps over a couple years.
The first thing that was done was to check out the air motors and make sure they are still operable. There was still oil in the air motor sumps. This meant that the basic machine will run. The air motor shift valves were removed and it was found they were in good condition.
The next part of the restoration is as follows; degrease, sandblast, prime and put the original color paint on the machine. The machine had to be degreased, since the oil that is in the air motors ends up all over the frame. This is due to the air that goes into the air motors and has oil in it to keep the parts lubricated during operation. Years of use builds up a thick coating of oil and dirt that had to be removed from the entire frame. Once that was done the entire machine was primed with grey bridge primer, a very resistant sealer to oil and grease. The final top coat of paint of Gardner Denver Green was put on the entire machine.

Next we had to work on the linkages, air lines, shifting valves and the motor control lever that was frozen, and also dipper chains that was totally stiff from rust and contained years of grease and dirt. It took a week of soaking to clean the drive chains. We also had to remove the drive motor controller and soak it with Kroil to break it loose. The last thing we worked on was the removal of the shift valve and then cleaned it out. All of the parts were reassembled and the mucker was ready to go. We spent about 2 months working on the moving parts on the mucker to get it running correctly.

Mucker Operation
The restoration took several years between the acquisition, sandblasting, painting, fine tuning and operation. The picture below shows the engineers checking out the machine.

The pictures below show the mucker in operation.


  1. Is there a way to roll up the dipper chains if you don't have it connected to a compressor??

  2. Also, do you know of a place to order the platform that you stand on??