Changing Fuel Filters: Bobcat 743 Step-By-Step Guide

Changing the fuel filter on a 743 Bobcat is a maintenance task that some users may need to perform. There are a few different ways to approach this task, depending on the specific model of the 743 Bobcat and the tools available. Some users have reported issues with the glass bowl filter, which can be prone to chipping and breakage. One solution is to replace the original filter housing with a modern filter housing designed for a screw-on filter. Others have suggested converting the cartridge fuel filter to a spin-on Bobcat filter using an adapter. In addition to the filter itself, it is important to inspect and replace any gaskets, O-rings, and fuel lines as needed to ensure a proper seal and prevent leaks.

Locating the fuel filter

The fuel filter on a 743 Bobcat is a cartridge-style filter with a glass bowl at the bottom. This style of filter can be challenging to replace, as it requires handling the glass bowl carefully to avoid breakage. There is also a risk of fuel spillage during the replacement process.

Some 743 Bobcat owners have opted to convert the cartridge-style fuel filter to a spin-on filter, which is easier to replace and does not have the same breakage and spillage risks as the cartridge-style filter. This conversion can be done by purchasing a conversion adapter and switching the fuel lines to the new filter head. The spin-on filter is the style currently used on newer Bobcat machines.

It is important to note that the fuel filter is not the only component in the fuel system that may need maintenance. The fuel pickup line, for example, can get soft and deteriorate on the inside, blocking fuel flow. Therefore, it is recommended to inspect other components in the fuel system while changing the fuel filter to ensure they are in good condition.

Converting to a spin-on filter

To convert to a spin-on filter, you can purchase a conversion adapter. This will allow you to use the newer style spin-on fuel filters that current Bobcat machines use. The part number for the assembly with the filter is 6667353, and it should cost around $40-$50. You can contact your local Bobcat dealer to purchase this part. The assembly includes a filter and a new mount, and you will need to switch your fuel lines around to fit the new filter head.

Another option is to change the entire filter head. However, this method may require redrilling holes and purchasing new fittings, which can be more complicated.

One user reported that they purchased a conversion adapter for $49.62 (Rayco part number INCAV) and used the Donaldson spin-on fuel filter (part number P-550248), which cost $8.72. They reported that this was an easy and fast conversion.

Replacing the filter and gaskets

To replace the filter and gaskets on your Bobcat 743, follow these steps:

Firstly, locate the fuel filter. You should be able to see it by following the fuel line coming from the bottom of the fuel tank. Once you have located the filter, you will need to drain the fuel. There is a drain on the bottom of the filter assembly to remove water; the filter acts as a water separator.

Next, you will need to remove the old filter and clean the pickup stem inside the filter. Install new gaskets around the filter and stem, ensuring that all surfaces are clean and free of debris. Replace the old filter with the new one, following the manufacturer's instructions or a diagram.

It is important to note that some Bobcat 743 models use a glass bowl filter, which can be prone to chipping and breakage. There is an option to convert to a spin-on filter, which may be more durable and easier to replace. This conversion can be done by purchasing a conversion adapter and using a spin-on fuel filter from Bobcat or another manufacturer.

Finally, check all fuel lines and connections for any signs of wear or damage. Replace any lines or connections that appear cracked or damaged. Ensure that all clamps and bolts are tight and secure.

By following these steps, you can replace the fuel filter and gaskets on your Bobcat 743, ensuring proper fuel flow and engine performance.

Draining water from the filter

To drain water from the filter, first locate the filter by following the fuel line coming from the bottom of the fuel tank. Once you have located the filter, look for the drain at the bottom. This drain is specifically for removing water, so you can be confident that you are doing the right thing.

There are a few ways to improve the process of draining water. One way is to switch to spin-on filters, which incorporate a water separator inside them. This eliminates the need for a glass bowl, which can be cumbersome and prone to breaking. Another option is to buy a modern filter housing for a screw-on filter, which is easier to replace and more convenient overall.

It is important to note that some older Bobcat models do not have a water separator in the stock filter. In this case, the filter only drains out fuel, and a plastic element or baffle in the glass bowl is needed to separate water.

Troubleshooting a malfunctioning filter

If you suspect that your Bobcat 743's fuel filter is not working as it should, there are a few things you can check. Firstly, the filter acts as a water separator, so if you notice water in the fuel, this could be a sign that the filter is not functioning properly. Another indication of a faulty fuel filter is if your Bobcat starts choking or stalling. This could be due to a lack of sufficient fuel supply, which can cause the engine to stumble or stall while driving or idling.

You might also experience trouble starting the engine or a sudden drop in fuel efficiency. If the fuel filter is clogged, it will restrict fuel flow to the engine, resulting in power loss when under load. This can lead to a 'P0171 System Too Lean' code being stored in the powertrain control module, which will trigger the Check Engine Light.

In some cases, a malfunctioning fuel filter can cause loud noises from the fuel pump as it tries to force fuel through a restricted supply line. It is important to address these issues promptly, as driving with a clogged fuel filter for too long can lead to more serious problems, such as fuel system component failure and engine damage.

If you suspect that your fuel filter is the culprit, it is recommended to consult a professional mechanic or refer to your owner's manual for guidance on replacing the filter.

Frequently asked questions