Husqvarna PG820 User Manual

English -

 23

Used correctly, the machine is an extremely low-main-
tenance and reliable.

This section covers the general maintenance items 
that need attention on a periodic basis.

There are three main mechanical items to check:

1. Grinding Heads.

2. Planetary drive system.

3. Planetary seal.

There are 2 different grinding head options:

11. Conventional / Demolition heads—designed for 
heavy duty preparation grinding where an extremely 
robust system is required.

2. Spring steel head system—designed more for fi nish-
ing or lighter grinding applications.

CONVENTIONAL/DEMOLITION HEADS

The below diagram illustrates the main parts compris-
ing this type of grinding head.

1. Head mate

2. Head plate

3. Head lock

4. Head spring

The interrelation between the above four components 
enables a dynamic system which is both robust and 
fl exible.

The head pins are fi xed to the head plate giving rigid-
ity and stability. The head mate is situated above the 
head plate and is held in place by a series of holes 
– head pin holes.

1. Head mate   

          1. Head plate

2. Head pin hole 

          2. Head pins

Between the head plate and head mate are 3 white 
silicone springs which give shock absorption and fl ex-
ibility in the system.

The head pins are able to move within the head pin 
holes, creating a shock absorber type system similar to 
that in most motor vehicles.

Over an extended period of time, the head pin holes 
wear open. Along with this, the head pins wear and 
reduce in diameter. This combined wearing of the two 
creates excessive movement or “slop” within the grind-
ing heads. This “slop” will eventually cause vibration 
whilst the machine is operating.

Routine checks for slop in the grinding heads are 
recommended. Life expectancy for grinding heads can 
vary between 6 and 12 months depending on amount 
of usage.

Replacement heads are available and simply bolt into 
place when the old ones are removed

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