Washing Machine Drive Belts

The Washing Machine Drive Belt

The drive belt in your washing machine, like many other spares, is a much maligned  component that is or at least has, been blamed for being a weak point in a washing machine or washer dryer without any real justification. 

There is a myth that washing machine belts stretch and, since about the end of the 1970's this simply has not been particularly true. In old top loader or twin tub washing machines where old belt technologies were used then yes, belts did stretch but on modern machines this is most often not true.

We think that some of these urban myths have come from the old types of belts, general ignorance by some and also from belts used in cars stretching but, bear in mind that a belt in a car turns more and is under greater load.

Some companies, like LG, use this myth to their advantage when selling their Direct Drive system where the motor stator is put onto the back of the tank. It's no more reliable than a belt system and no more stable either, but these companies are trying to pitch the notion to you that a drive belt is a bad thing and unreliable when it isn't really. It does however play to the urban myth.

Of course, like many other components they can and, do go faulty but very often not in the way that people would think.

Washing Machine V Belts

A "V belt" as we refer to it is a very simple drive belt that has been used since the dawn of washing machines. The name comes from the cross section of the drive belt which is a simple "V" shape with a flattened point to it. The belt will run in a single grooved motor pulley and then to the drum pulley and this will usually mean a more or less fixed set of speeds that can be employed. 

It also means that the belt never moves (bar one of two exceptions to the rule) and therefore is tremendously reliable for the most part, rarely if ever actually failing.

This is the simplest form of belt and will, these days, generally only be used on the most basic of washing machines.

Washign Machine Poly V Belts

Poly V belts as we call them or also called multi V belts are flat looking belts with multiple grooved tracks in them and since about the late 1980's into the early 1990's have more or less become the standard type of belt used in washing machines, washer dryers and tumble dryers as well.

For the most part these belts are again, hugely reliable.

We have, like the standard V belts seen on the odd occasion one of these belts becoming stretched slightly but you probably would not be able to detect that with the naked eye as the belt doesn't go slack as such, I'll explain more below. 

Why Washing Machine Drive Belts Fail

Rather than just allowing you to order a new drive belt and replace it without telling you a few things would be, in our opinion, a little remiss on our part. As a general rule there will most often be a reason for the belt to have failed and it is good practice to ensure that if you replace the drive belt, that the new one isn't just going to be torn up as well.

One of the most common and likely cause of a washing machine belt failing is that the drive belt will be torn up if the drum pulley especially runs off true, when that happens the belt clips the edge of the pulley causing it to get frayed and torn up. Usually this is caused by some sort of misalignment caused by something else failing, usually it's the drum bearings starting to go that allow the drum pulley to move very slightly, but enough to allow the belt to run off true.

If the old belt on your washing machine is frayed and torn up, check that first.

All modern washing machines have an OOB (Out Of Balance) or ABC (Anti-Balance Control) system in them to control out of balance situations. You can find out more about those from this link explaining some of the most common reasons why a washing machine will not spin.

How this works is that the motor tachometric generator, which detects the speed of the motor, will detect minute slippages from the belt which allow the electronic controller to "sense" that there is an imbalanced load in the drum. Now, most people think that the belt is simply a means of transferring motion from the drive motor to the drum but, that is no longer the case and hasn't been for some years, the belt is also an integral part of the control system and has to work properly.

What this means is that the belt has to be very tight, often seemingly impossibly tight so that it can detect these minor changes and the slippage. If the belt is too slack or is faulty, allowing the belt to skid etc., then the anti-balance will kick in and the drum will either not move or it will not spin as too much slippage is detected. It si vital that you get teh correct drive belt and that it is fitted correctly and is tight enough or you will likely have problems with spinning.

Ordering A Washing Machine Drive Belt

Unlike a lot of washing machine spares, drive belts will often have the size information printed on the actual belt itself, which can be handy but not always.

Like all spares manufacturers spares systems are model/serial number/production code/part number driven. The systems that we find spares on will not recognise the size information and to a manufacturer the drive belt will simple be a part number with the description "drive belt" and that's usually about as much information as we will get.

So, when you enquire about a washing machine drive belt please have the information to hand as it will allow us to identify the belt quickly and, most often, any alternatives that are available.