There is a short piece of pipe pinned to the eyebolt inside of the spring, which prevents having too much tension on the spring. The nut on the front is the adjusting nut. This nut has a washer next to the spring, to keep the spring from being forced over the head of the nut. This nut should be tight against the pipe. With the end of the rear nut against the pipe on the bolt, there should be 1/16 of an inch from the back of the pot lever to the head of the nut when the machine is in casting position. This 1/16 of an inch adjustment gives the correct lockup to the pot and also prevents breaking the lever by too much pressure.
The pot lever spring should be examined frequently, as back squirts will be caused by a spring which is broken or worn. This trouble is caused by not giving pressure enough to the mouthpiece when it is being locked against the mold for the cast.
A lever spring weak, worn, or out of adjustment will also cause an uneven height of the matrices, due to the lack of pressure during the cast.
When it is necessary to remove a pot lever spring, pull the pot forward by hand, place a support beneath the pot jacket to hold the pot lever roll off the cam. Remove the pot balancing spring, take off the rear nut on the eyebolt and push back on the lever. The spring can then be removed.
The roller in the pot lever has nine anti-friction roller bearings. These rollers should frequently be examined for wear, and if found worn should be renewed, because a set of worn anti-friction rollers will also cause an imperfect lockup. When renewing these rollers, put in all nine new ones. If a roller is worn or broken, or the bearing pin or pot lever roller worn, there will be play between the lever and cam, which will prevent a tight lockup.
To take out the pot lever: Pull the pot forward by hand, place a support beneath the pot jacket, remove the balancing spring, loosen the screw in the upper shaft bearing, and pull the shaft out. On the upper shaft bearing on each side of the pot lever, are washers of varying thickness. These washers are for the purpose of adjusting the pot lever sidewise so it will not bind on the main cams. When taking out this shaft be careful that the washers are not lost or mixed.
Take out the wing pin that holds the eyebolt to the pot jacket. Place the lever on the bench and take out roller bearings by releasing the set screw and pulling out the roller pin. Before replacing the bearings, in the lower roller, coat them with vaseline or hard grease. By placing a small piece of an old keyboard rubber roll in the hole, so the bearings fit around it, they will be held in place until the pin is slipped through. The pin will force the rubber out.
Fastened to the back of the pot lever, at the right-hand side, is the pot return cam shoe. As the main cams revolve, the pot return cam, fastened to cam No. 9, comes in contact with the shoe, pulling the pot away from the mold after the slug has been cast.
Removing a Pot
To remove a pot from a machine: Remove the plunger, dip as much metal out of the pot as possible. Lower the first elevator to the vise cap, and let vise down to second position. Remove the mold slide. Take off the pot leg caps. Loosen the front adjusting screws in the pot legs. Loosen the nut on the pot lever eyebolt, to release the spring tension. Take out the pot lever shaft, and remove the pot lever. Take off the mold disk shield and pump stop bracket. The pot can then be lifted out by placing a rope through the supports on the jacket for the pot lever shaft, so that the pot can be raised up while it is being guided out of the machine by taking hold of the bottom of the pot legs.