3.0 mercruiser

[Leonard Ray]

I have a 3.0 that will not pickup the water to cool the engine. Does the boat need to be move before it will work or just in the water.I have checked and nothing is cloged up. water pump?
Thanks
L RAY

 

[Joshua Nichols]

Re: 3.0 mercruiser

Nope doesn't have to move to pick up water. If they worked that way engines would overheat idling.. Bet your impeller is out.. Drop the lower unit and put a kit in... Needs to be done yearly anyhow.. Kinda risky not to

 

[Bifflefan]

Re: 3.0 mercruiser

No fins left on the impeller, is what im thinking.
It should idle all day sitting still and be cool as a cucumber.

 

[Leonard Ray]

Re: 3.0 mercruiser

Nope doesn't have to move to pick up water. If they worked that way engines would overheat idling.. Bet your impeller is out.. Drop the lower unit and put a kit in... Needs to be done yearly anyhow.. Kinda risky not to

The water pump is on the engine.Is there another one in the lower unit?

 

[Joshua Nichols]

Re: 3.0 mercruiser

Yes sir... It picks up the water and moves it to the engine... Called a impeller and or water pump..(one on your engine is a water pump too but just moves the water though the water passages on the engine). Just a rubber fan shaped thing... Normally they fail and all the fins fly off and go all in places they shouldn't.. Plugging up things.. It is why they should be changed out every season.. or sooner in the saltwater... If you don't change em regular you take the chance of overheating and frying the block.. Hence people who know put em in every season..... It's in the lower unit on the mercruiser.. Here is a picture of what one looks like

 

[dwoodard170]

Re: 3.0 mercruiser

Is changing the impeller something a novice with a socket set can do or should this be left to the experts?

 

[Joshua Nichols]

Re: 3.0 mercruiser

It's cake... Something you should learn to do anyhow... If you have a socket set you are already dangerous.. Get ya a repair manual...http://www.youtube.com/watch?v=zHPnEVmR6qE
here is a video to show ya how it goes.... You dont have to take the whole out drive off so dont freak out