What retains the impeller on the drive shaft on a 4hp ?

[dman535]

First time ripping apart an outboard to this extent. When the impeller came off I heard something go flying.. What am I looking for ?<br /><br />Thanks<br /><br />Derek.-<br />Johnson 4HP

 

[Xcusme]

Re: What retains the impeller on the drive shaft on a 4hp ?

A service manual....<br /><br />You could have lost the impeller drive pin or key. This keys the impeller to the driveshaft. Without it, the driveshaft can't rotate the impeller

 

[dman535]

Re: What retains the impeller on the drive shaft on a 4hp ?

What does the key look like ? is it just a steel pin ? Is this a marine specialty item or something I can make myself ?

 

[Xcusme]

Re: What retains the impeller on the drive shaft on a 4hp ?

It's not too hard to describe , but may be difficult to envision. The key is small. If you can imagine the capitol letter " T "<br /><br />Rotate the letter T , 90 degrees to the left. The now horizontal 'leg' of the T fits into the hole on the drive shaft. The vertical part of the T engages the 'key way' in the center of the impeller. You could use a short piece of steel rod inserted into the drive shaft with enough sticking out to engage the impeller, but there wouldn't be too much bearing surface in the impeller key way, that's why it's designed to look like the letter 'T'. Personally, I'd order a replacement from a Johnny/Rude dealer. On a 1976 4HP 'Rude , the part number is 321130. BTW, this part comes with a water pump repair kit.....