Running a dry motor?

[ba229]

My motor starts fine most of the time (ie first pull just like it should) but sometimes it can take 5 or 6 pulls to get it going.

this is no drama except when in a fast moving body of water.

so recently i have been starting the motor while the boat is still on the trailer just to make sure it will fire.

this running of the motor with no water lasts no more that 2 seconds.

Am i doing any damage to the impellor or other components?

[Oldyella]

ba
What happens, is the impeller has more resistance within the W/P housing when dry. cranking the motor can delaminate the rubber from the inner brass bush and the impeller will not turn, but the shaft will. Also, as was raised in this post, pieces can break off and clog the cooling passages. These are very hard to remove. In Queensland, where most of you guys are, the hot climate would make it even worse, as the waterpump would dry out very quickly when stored. Best practice is to either start it at the ramp on the flusher (if water available) of strat it at home before you leave.

[Bob]

:-[
Ba
I have replaced the impeller in my Mariner and noticing the tight tolerances and the drag on the impeller between the stainless housing, I will never start an outboard out of water even to see if would crank . It is not worth the effort .
Regards

Gon Fishun