How to adjust belt tension on a Husqvarna riding lawnmower, step by step


One of the core components of a Husqvarna riding lawnmower is the drive belt. The mower blades are driven by a drive belt that connects them with the engine crankshaft pulley. This belt is also called a blade belt. If the belt malfunctions, the lawnmower won’t move. If the belt is worn out, the lawnmower moves slowly because the belt slips on the pulley. If the belt is loose, it will keep your blades from rotating. All these issues require knowing how to adjust the belt. This article will help to adjust the belt tension with a step-by-step approach. 

How to adjust belt tension on a Husqvarna lawnmower, step by step:

  • Step 1. Park your lawnmower in a flat location
  • Step 2. Disconnect the spark plug
  • Step 3. Turn the log lever
  • Step 4. Inspection of blade belt
  • Step 5. Adjustment of the drive belt
  • Step 6. Check the blades

How would you know that your belt needs adjustment or not? There’s a long belt that goes from your blading engagement by your steering wheel down to your mowing deck. That belt stretches over time. This causes the belt to slip. If you feel this, then the belt needs adjustment. If you have a Husqvarna riding mower and don’t know how to tighten the drive belt, don’t panic. This blog explains how to adjust the belt tension on a Husqvarna riding lawnmower. IT will give you an insight into the tools you need, the technicalities you should know, and the precautions you should take.

Step-by-step Guide:

Adjusting the belt tension itself is a relatively simple process. However, opening the mower base and exposing the system can be technical and somewhat complex for newbies. Here the easy-to-follow steps will help you with performing the job at home.

● Step 1: Park your mower in a flat location

Place the lawnmower on an even, smooth, and plane location. This helps to get easy access to the underside of your mower. Please do not tilt the Husqvarna lawnmower on its side, as oil can run from the reservoir to the engine’s wrong parts. Use the parking brake to keep it from moving. If you have a lawnmower lift, you can use it to raise the mower so that approaching the base becomes easier.

Tip: Let your Husqvarna mower run in a well-ventilated area for a few minutes before starting. This will warm up the engine and oil. If the belt and pulleys run for a while, they will become easier to move by hand. This will make the task somewhat easier.

● Step 2: Disconnect the spark plug

As a safety step, it is good to disconnect the spark plug. That will ensure that the engine does not unintentionally start. You will find the spark plug on one side of the combustion chamber; unplug it. Some people ask if there’s a need to remove the Husqvarna mower’s cutting deck while adjusting your mower or blade belt. It both has advantages and disadvantages. In some types, removing it will make your approach to the belt components easier. For other types, just lowering the mower deck to its lowest position will give you enough room.

● Step 3: Turn the log lever.

The log lever serves a single purpose of engaging or disengaging the Husqvarna mower blades. Locate the log lever that is extending from the top of the control panel nearby the steering wheel. It turns at a 90-degree angle as it comes out of the control panel and extends to the right. On the end of the lever, there is a paddle handle. Rotate the log lever by holding the paddle handle away from forward away from you to engage the blades. While operating, if you notice a 2-3 seconds delay instead of a 0.5 seconds delay, the belt is loose. Now, pull the lever back to engage the blades.

● Step 4: Inspection of blade belt.

Next, you need to locate the Husqvarna blade belt. You can find it across the belt and pulley system underneath the deck. You can approach it from the mower’s base along with the blades, so you must have your mower on a raised platform. Before adjusting, you must look at your belt and make sure that there are no cracks. Suppose you see some cracks and chunks at this time. It would become critical to replace the belt. Next, you must inspect that your spring arm is working correctly. Make sure that it moves back and forth correctly.

Underneath the deck, check by hand that the spring attached to that spring arm is a bit slack, and the belt is easily stretched by hand. Also, check the sag of the belt as it passes over pulleys. If it is sagging below, it needs tightening. If it feels too tight, you need to loosen it. This will give you a complete analysis that which components must be tightened. Moreover, there is a cable that originates from the blade engagement level all the way down to the mower deck connecting the spring arm. It gets extended over time, so the belt gets loose.

● Step 5: Adjustment of mower or blade belt.

Now we can start with the adjustment. At the point where the cables come down and attach to the pulleys, there’s a small bracket from where the cable is adjusted. This is the same point where the cable from the blade engagement lever is connected to the spring arm. As the deck and blades are disengaged, everything beneath the deck is in a slack position. The same screws you need to tighten are the screws over the spring arms. Now take an adjustable wrench and unbolt the screws and washers, push the bracket away from the spring, put the bolts back in position, and tighten them up by wrench. You need to set a proper distance between the bracket and spring to tighten or loosen it.

In the case of Husqvarna, you need a 10 mm wrench for the bracket bolting and unbolting. When you are done with adjusting the belt, push the log lever away from the steering wheel to engage the mower deck and blades and check whether the spring is further stretched by hand or not. In an ideal position, it should be tight without any stretching caused by the hand. The belt has been adjusted. Also, you can always grease the belt while operating. Run it by hand to give it a few cycles. This will help lubricate the pulleys too. In the end, tighten any loose connections the pulley might have. Check all springs if they are free to move.

● Step 6: Double-check the Blades.

You need to check if the belt and pulley system is working. Use a pair of heavy safety gloves, twist the mower blades and check if the belt moves over pulleys without lagging or sagging. Reconnect the spark plug, and start the Husqvarna engine. Now you can see if the belt and pulleys are driven correctly. If they are, your blades should be continually moving and instantly startup without any delay.

Note: If you want to loosen the drive belt, you need to push the log lever away from the steering wheel, and you have to pull in the spring arms. You’ll be doing the opposite of what you did for tightening the belt.

Additional safety concerns:

We all are aware that blades can be very unsafe to operate without taking preventive measures. Also, when you are adjusting your drive belt, there are some safety tips that you should take into account.

1. Always Check the Manual

Always read the Husqvarna manual! Ensure that you know every detail about the drive belt. The manual will give you all the basic details you need. Ensure that the belt you use is specifically made for your model. Moreover, match the numbers on the blade belt with the mower manual. Even a slightly higher or lower number can cause the belt to be too tight or loose. This also reduces the mower’s life.

2. Double Check the Blades

You should always double-check the blades to see if they’re moving correctly without whirring when you move the lever. This is to make sure that the blades will not start cutting up everything. So, when you move the lever, check the blades’ movement. Also, check them when closing the compartments. If the blades are suck, your belt will immediately break up as you try to start up the mower.

Frequently asked questions:

1. Why does my belt keep slipping off my lawnmower?

The drive belt may come over a riding mower pulley if it is too loose. This is the reason for its slipping too. As the belt is made from fairly flexible rubber to add heat resistance and flexibility. Over time, the belt gets worn out that elongates the belt. Also, the pulleys are supposed to be adjusted at a fixed distance. Over long-term operation, the distance between them may reduce due to the belt stretch and bolts’ loosening. Both these are the causes of a loose belt.

2. When should I replace my mower belt?

At first, there is no definite amount of time that a mower belt is supposed to last, but most of the mowers have short intervals, after which a belt requires adjustment. Typically, you should adjust the belt once in a while and replace it every two seasons. If you do hectic mowing in one season, you should replace it. This will help protect other critical internal components.

3. Does a lawnmower drive belt stretch?

Yes, a Lawnmower belt will stretch because of wear and tear after longer use. The mower blades rotate with high RPMs, so the belt itself rotates very quickly as well. Unlike the drive belt of cars, mower drive belts are less sturdy. It means that over time the belt gets loosened over repeated cycles of heating, cooling, and fast turning.

Final remarks:

A loose drive belt can be the reason for your Husqvarna lawnmower to slow down unexpectedly. Over time the belt will stretch. This will reduce the belt tension and can cause several problems. To keep your Husqvarna lawnmower operating properly, the belt adjustment is something you will come across from time to time. This article gives you an easy to follow guideline to adjust the drive belt on your Husqvarna lawnmower.

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