How To Tighten A Belt On A Craftsman Lawnmower

Although there are multiple crucial components inside a riding lawnmower, one of the most vital is the blade drive belt. This piece is responsible for turning the blades, so your machine would be little more than a tractor without it. If you own a Craftsman lawnmower, you will have to learn how to maintain your belts so that they last longer.

Over time, belts will start to crack and loosen, which can affect the mower’s performance. Typically, you can tighten the belt to squeeze a little more life out of it. However, on a Craftsman machine, there is no way to do this. Instead, you will have to replace the whole thing.

Although there are certain lawn mowers which allow it, you cannot tighten a drive belt on a Craftsmen lawn mower. Instead, you will need to replace it. To replace, remove the cutting deck, and pull the belt off the pulleys. Replace with a new belt and reattach the deck to begin using again.

Refer to your owner’s manual to see where there are springs and cotter pins. In some cases, you might have to use pliers to get them out. Usually, if the mower is relatively old or you haven’t done any work on it, the pins can get stuck.

We also recommend inspecting each piece for any dirt or rust. Be sure to clean any dirty components before putting the cutting deck back on.

There should be two front rods and two rear retaining arms. Each of these sections is held in place by either a pin or a spring (or both). You will also have to remove the PTO arm to disconnect the deck completely. Use a flashlight to make sure that nothing else is attached to the deck that may prevent you from pulling it free.

Finally, you may have to use a jack to raise the mower. Doing this will make it easier to slide the deck out.

Although the blade drive belt has a simple function, it is wrapped around multiple pulleys. This piece also attaches to the engine, where the crankshaft drives the blades. With some Craftsman lawnmower models, you will have to remove the belt from the shaft before you can remove the cutting deck.

If you are having trouble pulling the deck out, the belt is likely the cause.

Before pulling the old belt off, we suggest taking a photo (or two) of the current belt orientation. Doing this will make it easier to put the new one on and ensure that you don’t get it wrong. Because drive belts operate at such high speeds, any problems can cause cracks or fraying almost immediately.

In some cases, there may be a diagram printed on the deck itself for reference.

You have to make sure that the belt is oriented correctly before wrapping it around each pulley. There is a flat side and a V-shaped side. The V side will face the inside of the two larger pulleys, which are called mandrels. The flat side of the belt will face the inside of the two smaller pulleys. When you’re finished, the belt should resemble a T.

There are belt guides on each pulley that should keep everything in place. However, be careful not to jiggle the belt loose when reattaching the deck.

Slide this piece underneath the mower and reattach each arm with the cotter pins. Don’t forget to reattach the PTO arm as well since that is connected to the clutch. You will want to wrap the last belt loop around the engine crankshaft last. If you try doing it first, it will be harder to reposition the cutting deck correctly.

During this step, the wooden blocks will help again. Since they will elevate the deck, you can attach the arms with less tension on them. Once the deck is connected, adjust the height to ensure that everything is working correctly.

Related Questions

Is there really no way to tighten a belt on a Craftsman lawnmower?

Unfortunately, no. This is a deliberate design option by Craftsman. While tightening belts can extend their lives for a little while, they will fail sooner rather than later. So, Craftsman forces owners to replace the belt instead.

How often should a lawnmower belt be replaced?

There is no universal answer to this question, but many repair shops would recommend every two to three years if you use your mower regularly. Commercial lawnmower belts should be changed annually since they experience much more wear and tear.