How to Test an '87 EFI Fuel Pressure Regulator

When you begin to suspect that you have fuel-delivery problems on your 1987 outboard, one of the things that will bear inspection is the fuel pressure regulator. The fuel pressure regulators are inside the vapor separator tank, but they aren't inaccessible for testing; you can attach a compressor to a fitting to conduct the test. The most time-consuming part of the test is bleeding the pressure from the fuel lines properly. Once that is accomplished, the work should move quickly.

Things You'll Need

  • Paper tags
  • Small pan
  • Shop rag
  • Air compressor
  • Fuel hose
  • Propeller wrench
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Instructions

    • 1

      Turn the engine key switch to “Off.”

    • 2

      Attach paper tags to the primary lead wire from each ignition coil to indicate the coil to which it was connected. Disconnect the primary lead wires from the coils.

    • 3

      Push down the connector lock tab on the high-pressure fuel pump wiring and pull the connector free from the vapor.

    • 4

      Crank the engine in three-second bursts, 10 to 20 times. Once the fuel hose to the vapor separator is soft to the touch, crank the engine five more times.

    • 5

      Reattach the ignition coil primary leads to the coils from which you disconnected them, using the tags as your guide.

    • 6

      Remove the battery's negative cable from its post and isolate the cable outside the battery box.

    • 7

      Place a small pan under the pressure regulator nipple, on the bottom or side of the vapor separator tank. Wrap a shop rag around the hose and nipple. Crimp the spring-loaded connector and push it and the hose off the nipple.

    • 8

      Connect an air compressor to the pressure regulator nipple, using a length of fuel hose.

    • 9

      Turn the compressor on and apply 45 psi of pressure to the regulator nipple. Shut the compressor off when 45 psi is reached. The pressure will stabilize at or above 34 psi.

    • 10

      Replace the regulator if it does reach 45 psi or if it does not stabilize at or above 34 psi when the pump is turned off.

    • 11

      Push the fuel line back onto the fuel regulator nipple. Slide the spring clamp over the nipple. Pressure the fuel system and inspect for leaks after maintenance is complete.