Leopard 40: Changing the Raw Water Pump

[Tom and Maje]

Tom changed the water pump">raw water pump on the engine, but it's not drawing water. Does anyone have an idea why?

Maje

[skipmac]

Unfortunately lots of potential reasons.

First, almost hate to ask this and I'm not being insulting (I've done this myself) I'm assuming you checked the really obvious like checking to make sure the seacock is open?

This is the raw water pump IE the one that uses a rubber vane impellor? When he pulled the old impellor out were there any vanes missing? They often break off and jam in the system somewhere and block water flow.

Is the pump higher than the water line? If so, any air leaks in the hoses between the water intake and the pump will keep the pump from self priming. Even if the hoses weren't removed sometimes messing around with the pump you can bump a connection and break the air tight seal.

Is he sure the new impellor is OK? Is the pump OK? Can he remove the cover, turn over the engine and confirm that the new impellor is actually turning? This does beg the question, why did he change this impellor? Just routine and time for a new one or was something happening with that engine?

[Tom and Maje]

It turns out that he had it on upside down.

Maje

[skipmac]

Now that would not have been one of my guesses.

What part was upside down, the impellor? Maybe this is one of those pumps that is mounted on the engine with the cover is on the back so you have to take the pump off the replace the impellor?

[Tom and Maje]

The pump it's self.

Maje

[rwidman]

Originally Posted by Tom and Maje

It turns out that he had it on upside down.

Maje

It should have pumped water backwards through the engine,

That's interesting because it looks like I will be replacing or repairing my engine's raw water pump before I go anywhere.

[Tom and Maje]

Originally Posted by rwidman

It should have pumped water backwards through the engine,

That's interesting because it looks like I will be replacing or repairing my engine's raw water pump before I go anywhere.

My advice is to take a close look at how the one that's on there now is positioned.

Maje

[rwidman]

Originally Posted by Tom and Maje

My advice is to take a close look at how the one that's on there now is positioned.

Maje

Something that works very well for me is taking digital photos before and during removal on projects that I haven't done before. Thanks for the warning.