Choosing the Fuel Filter for Your Fuel Pump's Inlet
Published on
June 6, 2024 at 10:46:31 AM PDT June 6, 2024 at 10:46:31 AM PDTth, June 6, 2024 at 10:46:31 AM PDT
When choosing to use an Aeromotive Fuel Pump on your vehicle it is imperative that you use it with the correct filters to ensure stable performance and prevent damaging the pump.
Aeromotive Fuel Pump Inlet:
If you are installing a fuel filter on the inlet of an Aeromotive Fuel Pump, be certain you do not use a filter that causes more problems than it solves. For pump inlet filtration use only 100 Micron Aeromotive Filters (P/N #12304, 12302) or an acceptable equivalent (see specifications below). Do not install the Aeromotive P/N #12301 or 12310 filter with 10-micron fabric element on the inlet of any Aeromotive fuel pump. They are however perfect for use on the outlet side of the pump, and this is the only location for which they are recommended.
You may run any brand of filter you choose on your car, just be certain that the filter element used on the inlet side of any Aeromotive fuel pump is no finer than 100-micron (no number smaller than 100), and has a surface area of 60 square inches or more.
Any filter element not meeting these criteria may fail to flow the full volume of the pump, resulting in both vehicle drivability and pump reliability problems. Aeromotive fuel pumps are engineered to be efficient, and can create both high outlet pressure and high inlet vacuum. The boiling temperature of any liquid varies with pressure. For example, the engine’s cooling system is purposely designed to pressurize the coolant in order to raise the boiling point. So how does this apply to fuel delivery? When a fuel pump has to pull through a restriction to get fuel from the tank a vacuum develops. This lowers the fuel’s boiling temperature, cavitating the fuel, turning it from a liquid to a vapor.
Bottom line: Inlet restrictions create vacuum, which causes cavitation, which in turn causes vapor-lock and fuel pump damage. Of course, drivability problems and even engine damage can result!
Lesson:
- Don’t combine high flow, efficient fuel pumps with poor flowing inlet filters.
- Don’t use fuel lines smaller than the pump ports.
- Don’t use fuel tank pick-ups or tank outlets smaller than the line
What size filter is right for me?
All Aeromotive pumps except the Pro Series EFI pump may use the Aeromotive filter #12304 with –10 inlet and outlet fittings and 100-micron stainless steel element. ThePro Series EFI Pump (#11102) requires filter #12302 with larger stainless steel element and –12 inlet and outlet fittings. The #12302 is also recommended for the EFI Eliminator Fuel Pump and the new #11105 belt drive pump (try 400gph or 2700lb/hr of fuel delivery at 100psi!!). Though Genuine Aeromotive Filters may be somewhat more expensive than the off-brand options, you simply must “compare apples to apples”.
What about a fine filter?
Fine filters are also necessary, but must only be installed on the outlet side of your Aeromotive fuel pump, never on the inlet. Options include the Aeromotive 10-micron units with fabric filters (pump gas) or micro-glass (E85 / alcohol), and the new, high-flow 40-micron (cleanable element) stainless steel filters. Given the alcohol content found in today’s pump gas, it is now necessary to frequently monitor and service any downstream fuel filters in use. Because fabric filters cannot be cleaned, keep a spare 10-micron element on hand for immediate service to eliminate engine fuel starvation and drivability problems when they become heavily clogged.