Replacing impeller Nissan 5HP

[Giorgio]

I need to replace the impeller in my Nissan N5B 5HP and I have a shop manual that shows where the impeller is on it's way to compleatly stripping the gear case, but no reference to how just replacing the impeller.<br /><br />Do I have to remove the propeller, gear case, shaft housing, propeller shaft and clutch just to change the impeller? or is there a simpler way?<br /><br />Any advise is welcome and greatly appreciated

 

[buckeye_sean]

Re: Replacing impeller Nissan 5HP

If you have a Clymer service manual, it should have a section on specifically replacing the impeller. Although they wrote it in a general sense for all size Nissans. There is also a blowup of different models and any special processes/parts necessary for each model.<br /><br />If your 5hp is similar to my 9.9hp installation should be very similar to this:<br /><br />First, drain the gearbox oil<br /><br />Second, you need to remove the entire lower unit where the gearbox is (should be 4 nuts below the skag plate) and you will have to disconnect the shifter linkage before pulling it out. Once you have slid the whole lower unit out, go put it on a workbench or in a vise.<br /><br />You should see a small plastic "box" that is in line with the driveshaft on top of the gearcase. Inside is your impeller. Remove the bolts/screws and be careful not to lost the shaft pin when removing the impeller. Replace all parts that come with your rebuild kit. (Different repair kits will come with different parts so pay attention to how everything comes out for reassembly.)<br /><br />Once you have completely installed the new impeller carefully slide the lower unit back in and bolt it in place. Don't forget to attach the shifter linkage!<br /><br />AND - this is a biggie - make sure you put new gear oil in the lower unit BEFORE you fire up the motor.<br /><br />This is sort of a quick rendition - but should be what you're going to run into. Good luck!

 

[phatmanmike]

Re: Replacing impeller Nissan 5HP

why do you have to drain the oil?

 

[buckeye_sean]

Re: Replacing impeller Nissan 5HP

Well I shouldn't said you HAVE to drain it. Although my Clymers manual said to - I guess they figure you should change gear oil when you replace the impeller.<br /><br />Scheduled service???<br /><br />I'm guessing here - anyway it would probably be good to change it anyway.

 

[phatmanmike]

Re: Replacing impeller Nissan 5HP

gotcha

 

[Giorgio]

Re: Replacing impeller Nissan 5HP

Well, thank you guys for the advise. The motor is only about 5 hours old, but the prior owner didn't use it for 9 years and now there's no water coming out of the column, so I am ASSUMING that the problem is that the impeller got old and melted or something...

 

[buckeye_sean]

Re: Replacing impeller Nissan 5HP

If it only had 5 hours on it, it wouldn't have worn out - but if it was sitting that long there is a good chance it just dry rotted.