Sealing agitation systems
Most sealcoating equipment includes agitation, usually consisting of a shaft extending through both ends of the tank. A seal around the shaft prevents the sealer from being released. Always keep seals maintained and replace them when necessary.
Some agitators have packing glands, which is a gland with mechanical packing inside, wrapped around the shaft with a packing pipe holding it in. Always check the tension of the nuts which hold the packing pipe. The nuts will work themselves loose, enabling sealer to run down the shaft and into the bearing.
Once the abrasive material enters the bearing it will erode the ball bearings inside. Bearings can be expensive to replace. Once the packing pipe has been tightened down to its maximum, put more mechanical packing inside.
Other sealcoating agitation machinery includes a rubber seal, a steel plate, and a bearing. Keeping the nuts tight on this type of machinery will apply pressure on the rubber seal, keeping it from leaking sealer. Always replace the rubber seal at the first sign of leakage.
Worn seals also allow sealer to leak on machinery. You appear more professional pulling onto a jobsite with a clean machine rather than on which appears as if it were just pulled from a tar pit.
Michael Bechtel, SealMaster/Thorworks Industries, began fabricating and welding sealcoating machinery in 1980. Since 1986 he has been selling equipment and providing troubleshooting advice to contractors.