I have just installed an MMI water pump with the sealed bearings and I hear a tapping (or maybe it is a slapping) sound coming from the vicinity of the water pump at an idle. When RPM is increased to about 800 the sound diminishes and goes away completely at 1000 RPM. This noise was not present with the old Sherwood pump.
The new pump moves a lot more water than the old pump so I am wondering if this may account for the noise. Is it possible that the load on the pump shaft to accessory drive coupling is variable or pulsating at low RPM's (due to impeller surge) but then this load smooths out when the RPM's increase and the flow is more consistent?? Could this pulsating at low RPM's cause the tapping/rattling noise? Has anyone experienced anything like this?? I am also wondering if it is OK to run the engine under this condition since it is hardly ever at an idle?
Thanks for any help or comments.
Bruce
The new pump moves a lot more water than the old pump so I am wondering if this may account for the noise. Is it possible that the load on the pump shaft to accessory drive coupling is variable or pulsating at low RPM's (due to impeller surge) but then this load smooths out when the RPM's increase and the flow is more consistent?? Could this pulsating at low RPM's cause the tapping/rattling noise? Has anyone experienced anything like this?? I am also wondering if it is OK to run the engine under this condition since it is hardly ever at an idle?
Thanks for any help or comments.
Bruce
Comment