How to Change Your Filter

When changing your fuel filter, it is very important to flush all of the air out of the system.  If you own a Veggie Oil Conversions system, there are generally two filters, a pre-filter and a main filter.  The prefilter is see-through and you can usually visually tell if it is clogged.  In general, the amount of air that enters the system when changing the prefilter is not enough to need a fuel air flush after replacing.  The main filter is a bigger filter usually installed in a heated coil wrap.  When replacing this filter, it is very important to flush the air out of the system using the flush valve after replacing.

Prefilter:

1. Put a rag or towel under the filter to catch oil drips
2. Using a screw driver, a ¼” nut driver, or a 6mm nut driver, loosen the hose clamps on either side of the prefilter.
3. Quickly pull the filter out of the fuel lines and put it in a catch bin or the trash
4. Quickly install a new prefilter into the fuel lines.
5. Tighten the hose clamps
6. If the fuel level in your tank is above the level of the prefilter, then the tank will want to siphon while changing.  In this case, needle nose vice grips may be used to clamp the fuel line between the heated line and the filter to prevent fuel flow.

Main spin-on fuel filter:

1. Find a catch bin or rubber made or similar container that will fit under the fuel filter when removed.
2. On cars and trucks with a front mounted pull out fuel filter, lift the fuel filter out of the heated coil and place it in the bin. 
3. On trucks or cars with a hard mounted filter head, place the catch bin below the filter.
4. Unscrew the filter and let it drain in the bin before disposing of it.  If it is hard to unscrew, you may need to use an oil filter wrench from your local auto store.
5. Screw the new filter on.  In this case, make sure that your do not cross thread the filter.  Is should spin on easy, so take your time and make sure you are screwing it on without force. 
6. Tighten it by hand very tight and then reinstall the new filter into the coil if applicable.
7. Go into the vehicle, turn on the key but not the engine and switch the switches to Veggie Mode.
8. Find your “no-no” or fuel flush valve on the front of the vehicle and also put your catch bin below the drain of the “no-no” valve.  This valve is called the “no-no” valve because you never want this valve open when the engine is operating, only during a filter change.
9. If you have electric lift pumps, then open the “no-no” fuel flush valve at the front of the vehicle and wait for all of the air to flush and there is a steady stream of fuel flowing out.
10. If you have a mechanical manual lift pump, then open the “no-no” fuel flush valve at the front of the vehicle, pump the manual pump, and wait for all of the air to flush and there is a steady stream of fuel flowing out.
11. Close the “no-no” valve and switch you switches back to diesel inside the vehicle.
12. If the fuel level in your tank is above the level of the main filter, then the tank will want to siphon while changing.  In this case, needle nose vice grips may be used to clamp the fuel line between the heated line and the filter to prevent fuel flow.
13. You can alternatively fill the new filter with fuel/oil before installation and skip the air flush steps 7-11.