You or your dealer may have to troubleshoot the problem with the temporary installation of a water pressure gauge. There are charts that state what the minimum water pressure should be at different rpms. Your dealer should be aware of them or he can call the factory-dealer hot-line for technical help.

One common problem is an incorrectly clamped overboard water hose at the rear of the adapter plate. Sometimes the boat hull design, strakes, transducers, thru-hull fittings, trim tabs, etc. can disrupt the water flow to the motor at certain speeds.

Sometimes in exceptional circumstances, a 7# pressure relief spring and plunger may be substituted for the 10# spring.