How to Replace Excavator Pin and Bushing

When we continue to use excavators over time, their parts begin to wear and tear, especially the bushes and pins. These parts are easily replaceable, but you often need tips and guides to help you use and replace them. Here we will give you useful tips how to do this process trouble free.  

How to replace excavator pins                   

In case you don’t know, bucket pins hold a bucket to the digger to which it is attached. These pins include ram pins, digger link pins, and boom pins.

In the beginning, all the pins are fastened to their position. But these positions differ from one machine to the next.

Some diggers come with a large nut alongside a washer at the end of a pin. Others come with a hole through which you secure a bolt through the pin.

Some other machines come with a thread at the rear of the pin where you screw in the bolt.

Regardless of the system your excavator operates, the pin should come off without stress whenever it needs to be removed.

It is somewhat easy to remove the pins that lie at the machine’s deeper end. However, when you get upwards to the dipper arm and get to the kingpost through the boom, make sure the arm has adequate support before proceeding to remove the pins.

If you want to remove the booms so you can replace the kingpost bushes, get a forklift and a sling or a crane to assist you when removing and repositioning it.

When you successfully remove all the pins, the bushes come next. We advise you to replace both at the same time because they often wear and tear together. If you replace one part without the other, you might have more severe problems. These parts of a excavator will differ depending on the manufacturer of your machine.

How to remove digger bushes

Before we talk about how difficult it is to replace digger bushes, the first step is removing the former bushes. This process can be hard, but you can achieve it step by step.

First of all, it will be difficult to remove your digger bushes without damaging them. But not to worry, since they are already worn and torn, which is why we are taking them out in the first place, we can damage the bushes.

However, you must protect the digger’s arms from any form of damage.

Here’s how to go about it; these tips will help you remove digger bushes with less stress.

1. Employ force

When working with small excavators, a hammer and bar work great, especially if the bushes are weak and worn out. The bar should be larger than the bush’s internal diameter, but it should be small compared to the external diameter.

People who work with bushes of several sizes often contact engineers to build a stepped tool that can handle different bush sizes. It makes things easy and faster.

2. Attach a stud

Get a stub welded into the bush to help you place the bar through the bush, and then get it knocked out.

3. Weld around the bush for large bushes

When working with large bushes, it is good to weld throughout the bush’s radius. When the weld gets cool, it squeezes the bush and makes it small enough for you to remove it.

4. Remove the bush by cutting it out

You can cut a slot in its wall to allow you to shrink and remove the bush without stress. You can use an oxy-acetylene torch or something similar for the process.

If you are careless, you might cut the digger’s arm, and such damage is costly.

5. Use a hydraulic press

The good thing about hydraulic presses is that they are very safe. Unfortunately, many persons can’t lay their hands on this equipment. However, if you are in a place where you can access them, use a hollow hydraulic cylinder for this job.

How to replace digger bushes

So, we have gone through the process of taking out old bushes from your digger, but it isn’t the end yet. The next step is to replace the bushes with new ones. This process is also stressful, and you will need several pieces of equipment to handle the job at hand.

1. Hammers

Hammers are great to get your digger bushes in, but you must ensure that the bush doesn’t break or split due to excessive force. Many excavator bushes are made with induction hardened steel for better wear and tear resistance. However, they are prone to breaking when hammered.

2. Use Heat

Get a heat source and take it close to the bush and where you want to place it. The heat method is effective if you heat the bush housing. The heat will make it expand so that you can replace the bush before it cools and tightens.

Take note of the digger’s arm to avoid damaging the painting with the heat source.

3. Use the cooling method 

While you can use heat to replace the bush, you can also use the cooling method to do the same.

Rather than expanding the bush housing using the heat method, you can shrink the bush using the cooling method and place it in easier.

You can do this with Nitrogen at 195°C, but you need training and equipment for this. It is best to get an engineer to help you.

4. Use Hydraulic Press

Also, the hydraulic press needs specialized understanding and specific types of equipment. You need a hollow hydraulic cylinder and the knowledge of using it.

You can use a hydraulic cylinder alongside the heating and cooling method, especially when you work with large excavators.

Based on how to replace Excavator pin and bushing, using a hydraulic press for replacing bushes is most effective. If you want to use a hydraulic press, here are some cylinder suppliers to check out.

1. Taizhou Chuanhu Hydraulic Machinery Company is one of the best producers of hollow hydraulic cylinders, hydraulic pumps, pullers, cutters, etc. They supply products to customers in America, Europe, China, South East Asia, and the Middle East. Their products are compliant with GB15622:2005 and ISO10100:2001 safe working standards.
2. Hi-Force is a leading manufacturer, designer, and hydraulic product supplier in the UK. They offer products to many industries with products that can be as many as 2000. They include hydraulic jacks, pumps, pullers, cutters, cylinders, etc.