Onan genset impeller change R31

[spromisloff]

Any tricks to removing the water pump on the Onan 5Kw to remove the impeller? I spent 2 hours with the owner's and parts manuals yesterday, but couldn't quite get there. Also, removing the feed and discharge hoses are almost impossible given the tight space between their connections and the fixed outboard side of the enclosure box. An article such as Andrew's instruction on stuffing box adjustment would be great Thanks.

 

[R Baker]

I've done it twice.
First, remove side, top and end white panels. Remove v belt. Loosen four bolts and remove pump. Hoses can stay on the pump. Pry out the impeller and check & remove any loose impeller vanes.

 

[Irish Mist]

Yes is much easier if you take the sound shield panels off.. Make sure to find all the pieces and put some soap or lube on the new one as it will run dry for the first couple of seconds after you start it up again.. Should be easy to change. As in not complicated I'm about 1/2 hour to change

 

[bill46]

I hired a mechanic younger and smaller than I. He had a time of it.

 

[Irish Mist]

Must be harder in the 31 pretty easy on the 29

 

[JeffE]

The secret is to take the port side sound shield off (actually, just remove the bolts and push the panel as far to port as it'll go). Then you have decent access to the bolts holding the water pump in place. There's a spacer on the bottom bolt that you want to be sure you put back (ask me how I know🙂 ).

It seems like a silly design, since the impeller is an annual maintenance item, but it's a small generator and I guess they didn't have anywhere else to mount the pump.

What's really hard is getting access to the block drain for changing the coolant. I haven't quite figured that one out yet.

Jeff

 

[spromisloff]

Thanks to you all for the tips. My big mistake was not removing the side panel of the sound shield (apparently it is easier than it looks). Also, good to know that the hoses do not have to be removed. Hopefully will be less daunting next time around.