Merc 7.5 -- Impeller

[perkdp]

In general ,,, which direction does the drive shaft turn on these small Merc engines ? I think clockwise...... <br /><br />More specific, which direction should the fins of the impeller be bent inside the impeller cup / pump housing ? should end of the fins be pointing clockwise (ie..same direction the shaft turns) or oposite of shaft rotation ?

 

[Paul Moir]

Re: Merc 7.5 -- Impeller

Clockwise is correct.<br /><br />The blades should trail as it's rotated clockwise. That is to say, to assemble it you should turn the driveshaft clockwise while lowering the housing over the impeller.<br /><br />I hope that's clearer than it seems to me.

 

[perkdp]

Re: Merc 7.5 -- Impeller

Yes it is. The bad thing is that I've put it back together the ends of the fins "pointing clockwise" .... <br /><br />Which causes them to push against the sides of the cup as the shaft turns clockwise. <br /><br />If one turns the shaft clockwise while putting the cover over the impeller (on this motor) it will cause the fins to trail (point counter clockwise). <br /><br />The motor seems to be pumping fine the way i have it installed. But will probably wear the impeller out quicker and if the motor / shaft is turned with a dry cup,,, the fins will probably either flip back or break off. <br /><br />I guess I'll either go in and change it or keep a close eye for it to stop peeing. <br /><br /><br />thanks....