'88 OMC Cobra 3.0 Impeller

bjarnold1

Petty Officer 2nd Class
Joined
Nov 12, 2005
Messages
136
I recently replaced the impeller on my 1988 Bayliner OMC Cobra 3.0 I/O and the shop who did it last time installed it wrong as some of the fins were one way and some going the opposite direction. I took the boat out today for the first time and the temp was right around 170 but the valve cover was hot and started making a light ticking sound. When installing the impeller in the housing should I turn it clockwise or counter-clockwise?
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
40,581
I recently replaced the impeller on my 1988 Bayliner OMC Cobra 3.0 I/O and the shop who did it last time installed it wrong as some of the fins were one way and some going the opposite direction. I took the boat out today for the first time and the temp was right around 170 but the valve cover was hot and started making a light ticking sound. When installing the impeller in the housing should I turn it clockwise or counter-clockwise?

Clockwise or counter depends on how and where the pump is mounted. If its mounted on the starboard side and is belt driven, and is a left hand standard rotating motor, then the impeller will be installed counter clockwise. This is looking at the impeller in the pump housing from the front of the motor.

That said, a new impeller will have no problem being flipped around when motor first cranks and impeller is lubed with soap or glycerin.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,454
Here is a picture of the impeller in the housing
fetch


The impeller rotates the same direction as the engine since it is mounted on the back of the drive.
 

bjarnold1

Petty Officer 2nd Class
Joined
Nov 12, 2005
Messages
136
Thank you that's what I needed to know. I had the impeller reversed
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,454
Thank you that's what I needed to know. I had the impeller reversed
I am actually surprised it didn't flip around too. Sometimes when you turn off an engine it will rotate backwards slightly so some of the vanes may look slightly aimed backwards but the ones that are really compressed won't.
 
Top