Troubleshooting - Husqvarna 531RB Operator's Manual

Note: Make sure that you can not turn the locknut by
hand. Replace the nut if the nylon lining does not have a
resistance of a minimum of 1.5 Nm. The locknut must be
replaced after it has been put on approximately 10
times.
To examine the spark plug
CAUTION: Always use the recommended
spark plug type. Incorrect spark plug type
can cause damage to the product.
• Examine the spark plug if the engine is low on
power, is not easy to start or does not operate
correctly at idle speed.
• To decrease the risk of unwanted material on the
spark plug electrodes, obey these instructions:
a) Make sure that the idle speed is correctly
adjusted.
b) Make sure that the fuel mixture is correct.
c) Make sure that the air filter is clean.
• If the spark plug is dirty, clean it and make sure that
the electrode gap is correct, refer to
on page 24 . (Fig. 76)
• Replace the spark plug if it is necessary.
To sharpen the grass knife and grass
blade
WARNING: Stop the engine. Use protective
gloves.
The engine does not start
Check
Stop switch
Fuel tank
907 - 003 - 23.04.2019
•
•
•
To do maintenance every 100 hours
1. Remove the muffler.
2. Push the screwdriver into the slot and remove the
3. Tighten all screws and bolts. Make sure that all parts
4. Make sure that the clutch lining and clutch drum is
5. Remove the float chamber from the carburetor and
Technical data

Troubleshooting

Possible cause
The stop switch is in the stop posi-
tion.
Incorrect fuel type.
To sharpen the grass knife or grass blade correctly,
refer to the instructions that come with the cutting
attachment.
Sharpen all edges equally to keep the balance.
Use a single-cut flat file. (Fig. 77)
WARNING: Always discard a blade that is
damaged. Do not try to make a bent or
twisted blade straight and use it again.
unwanted material. (Fig. 78)
are correctly attached.
free from dirt, oil and grease. If not, wipe it of with a
cloth and an oil-free and lead-free gasoline.
clean the inside of the float chamber. (Fig. 79)
Procedure
Let an approved service agent re-
place the stop switch.
Drain the fuel tank and fill with cor-
rect fuel.
23