Land Cruiser Build Fuel Pre Filter

In this part of the Land Cruiser Build we install a fuel pre filter. One of the most important modifications you should be doing to any 4WD. A relatively cheap solution to prevent catastrophic and costly engine failure.

Why a Pre Filter?

Why did we install a fuel pre filter as part of our 70 Series Land Cruiser Build? As the name suggests, a fuel pre filter is a secondary fuel filter that filters your fuel before the factory one. We installed one in order to filter the fuel for any contaminants, mainly water, before the fuel gets to the factory filter. This ensures that water and any other contaminants should not get into your engine and cause some extremely expensive damage to your 4WD. We have all heard horror stories where contaminated fuel has destroyed the engine of a flash new 4WD.

Most four wheelers are touring and end up in some fairly remote areas. This leads to fuel contamination issues as some of these remote servos might have really old fuel tanks which can lead to a number of fuel problems. Also, when travelling long distances, especially in this massive country of ours, we usually carry extra fuel in jerry cans. It is super easy to contaminate your fuel when using jerry cans such as dropping your container cap in the dirt and so on. Having a pre fuel filter helps to reduce the risk of any of these potential contaminants getting into your engine.

Another reason to install a pre filter is that a pre filter is usually around 30 microns vs the factory filter of around 5 microns. The higher the microns the courser the filter, so the pre filter will remove any larger particles before the fuel gets to the factory one. This will help the factory filter deal with smaller particles as it is supposed to and extend its life. The pre filter will also work as the primary water separator and as you can see the bottom of the pre filter this allows you to empty any potential water before it can cause an issue.

Overall the pre filter maximises the protection of your diesel fuel system. A fairly cheap option to minimise a potential high cost without one.

Which Pre Filter?

So which fuel pre filter did we chose to install in this part of our Land Cruiser build?

We chose a Direction-Plus fuel manager pre filter kit as these are the most popular in the Australian market. Tried and tested in Australian off road conditions, so a no brainer for us. There are a range of suppliers where you can purchases these from. We decided to purchase ours from Western Filters. Western Filters have a kit that comes with a bracket, specific for our 70 Series Land Cruiser, all the necessary hoses and fittings, as well as detailed instructions on how to install the pre filter in your vehicle. This kit also allows you to install an oil catch can on the other side of the bracket.

See the below images showing you the Direction-Plus filter kit, with all the other parts we received from Western Filters. The kit contains the following:

• Direction-Plus 100 Series Pre Filter
• Fuel hose – 4 metres
• Hose clamps
• Brass fittings
• Zip ties
• Fitting instructions
• Stainless steel mounting bracket
• Thread sealer

The kit does come with M8 nuts and bolts, some wing nuts for mounting the pre filter to the bracket. We replaced all the nuts with M8 nyloc nuts to ensure that nothing comes loose while driving those bumpy tracks.

Installing the Pre Filter

Tools Needed:

You don’t need many tools for this job but this is what we used.

• 10mm and 13mm sockets
• Large flat head screw driver
• Wire cutters for the zip ties

Fitting the Bracket:

The first step is to install the bracket in the engine bay. In order to do this you need to remove the bolts holding the power steering reservoir which is behind the air box. You then need to slide the supplied bracket under the reservoir and refit the factory bolts. You’ll need a 10mm socket in order to remove these bolts.

The bolt closest to the air box is a real pain to get back in as you don’t have much space to get in there. Be patient and don’t drop too many “f” bombs. Once the bottom part of the bracket has been bolted on, you then need to bolt the final piece of the bracket onto the side of the engine bay. We replaced the supplied M8 nut with a nyloc nut.

Mounting the Pre Filter:

Now that the bracket is fitted, grab the fuel filter and using the supplied thread sealer add the two brass stoppers or blanks to the side that you don’t want to use. Once the two stoppers have been fitted add the two brass hose connectors / barbs. Once all brass fittings are nice and tight, bolt the fuel pre filter to the installed bracket. We used two nyloc nuts here instead of the provided wing nuts.

Connecting the Hoses:

Now that the pre filter has been mounted to the bracket, go to the other side of the engine bay and disconnect the hose from the factory filter that connects the fuel line from the fuel tank to the filter. You won’t need this hose any longer.

Now get the supplied fuel hose, which is in one piece, add one of the hose clamps then connect to the hose from the fuel tank. Tighten the hose clamp using a flat head screwdriver. You then need to run this hose up beside the engine towards the firewall, then across the top of the firewall to the other side of the engine bay, and then finally across to the fitted pre filter.

Once you are happy with the length of the hose, cut the hose, add another hose clamp and then connect to the left hand side of the filter. It does not matter which brass barb you connect to, we connected this hose to the one on the left hand side. Be sure to measure the hose correctly before cutting it. I would recommend cutting the hose slightly longer as you will have a bit left over and you can cut again if you need to shorten later on.

Now back to the other side of the engine bay and connect the hose to the factory filter using another hose clamp. Now run the hose beside or on top of the previously run hose all the way across to the pre filter. Now connect this hose using the last hose clamp to the right hand side brass barb on the pre filter. You will have excess hose remaining, so cut to the required length. Now make sure all the hose clamps are nice and tight one final time.

Use the supplied zip ties to secure the two hoses nice and neatly in the engine bay and along the firewall. See the images below to get an idea of how this should all look.

Priming the Fuel Lines:

Do not forget this step or you will be wondering why your car won’t start. Once all the hoses are connected, you need to prime the fuel lines. So basically suck fuel up from the fuel tank through the pre filter and all the way back into the factory filter.

To prime the fuel lines you need to go to the factory filter and you will see a small black round button. The button is about the size of a 10 cent piece. You will need to push this up and down for a few minutes to prime the lines. You will know that the fuel lines are primed when you can’t push the primer button any longer. Be patient here as this will take quite some time, 5 minutes approximately, and you will probably have a sore thumb afterwards.

Once your fuel lines are primed you can start the engine. If it doesn’t start then you probably haven’t primed the fuel lines properly.

Now that the pre filter is all fitted, no need to stress while travelling this massive country of ours. You will need to replace the fuel filter every 10,000 kms when you do your regular servicing.

A Must For Every 4WD

As we have shown you, installing a fuel pre filter in this part of our Land Cruiser build is extremely easy. You do not need to be an experienced mechanic to install one. This modification should be one of the first things you add to your 4WD as the cost benefit here is massive.

This fuel manager kit with the supplied bracket cost us $275 from Western Filters. A fairly small cost compared to the cost of a destroyed engine. We would highly recommend fitting one to give you that piece of mind when out exploring this amazing country of ours.

This is the fuel pre filter kit we added in this part of our Land Cruiser build on the Western Filters website – click here.

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Thanks for reading legends!

The thoughts of Peter.

This is not a sponsored post, we bought this gear and it’s an honest review of what we think about it!