Outboard prop won't go back on?

[ronsurf]

I've fitted a new impellor to my Evinrude 4 two stroke that has been in storage a while. Getting the drive shaft out was a bit of a fight. but it's all done now.

Except for the prop. This is making me scratch my head - the prop will slid on, but no far enough to get the split pin in. The drive to the prop is with a pin through the shaft. If I take the pin out of the shaft the prop will slide on far enough (just) to get the split pin in. If I put the pin in the shaft, the prop won't go far enough on to clear the hole to get the split pin in. Everything is in good condition, no bent pins, shafts or anything.

Hope that makes sense? Point is, I haven't changed anything, I took the prop off, did the impellor change, now can't get the prop back on. I've done this many times before without any problems, what on earth is going on? Any ideas?

 

[Alex_Blackwood]

I've fitted a new impellor to my Evinrude 4 two stroke that has been in storage a while. Getting the drive shaft out was a bit of a fight. but it's all done now.

Except for the prop. This is making me scratch my head - the prop will slid on, but no far enough to get the split pin in. The drive to the prop is with a pin through the shaft. If I take the pin out of the shaft the prop will slide on far enough (just) to get the split pin in. If I put the pin in the shaft, the prop won't go far enough on to clear the hole to get the split pin in. Everything is in good condition, no bent pins, shafts or anything.

Hope that makes sense? Point is, I haven't changed anything, I took the prop off, did the impellor change, now can't get the prop back on. I've done this many times before without any problems, what on earth is going on? Any ideas?

I would suggest a gentle tap on the pin to make sure it is fully "Home"

 

[VicS]

I've fitted a new impellor to my Evinrude 4 two stroke that has been in storage a while. Getting the drive shaft out was a bit of a fight. but it's all done now.

Except for the prop. This is making me scratch my head - the prop will slid on, but no far enough to get the split pin in. The drive to the prop is with a pin through the shaft. If I take the pin out of the shaft the prop will slide on far enough (just) to get the split pin in. If I put the pin in the shaft, the prop won't go far enough on to clear the hole to get the split pin in. Everything is in good condition, no bent pins, shafts or anything.

Hope that makes sense? Point is, I haven't changed anything, I took the prop off, did the impellor change, now can't get the prop back on. I've done this many times before without any problems, what on earth is going on? Any ideas?

You don't identify the exact model by quoting the model number but I have a similar problem with a 6hp Evinrude. ( The same problem if yours is a DL model with reverse gear.) It appears to be caused by corrosion expanding the prop hub. With mine I had to leave out a spacer washer behind the split pin but that is not an applicable fix for the standard ( no reverse) 4hp.

 

[wallacebob]

Back to front?

 

[ronsurf]

You don't identify the exact model by quoting the model number but I have a similar problem with a 6hp Evinrude. ( The same problem if yours is a DL model with reverse gear.) It appears to be caused by corrosion expanding the prop hub. With mine I had to leave out a spacer washer behind the split pin but that is not an applicable fix for the standard ( no reverse) 4hp.

Ah, this sounds likely. So I'm not losing my mind!
Mine is a 4 hp with no reverse gear. I'm reluctant to drill holes to make it fit, so I'm considering a thinner split pin.

 

[VicS]

Ah, this sounds likely. So I'm not losing my mind!
Mine is a 4 hp with no reverse gear. I'm reluctant to drill holes to make it fit, so I'm considering a thinner split pin.

Another hole drilled at right angles to the original through the shaft for the split pin might be a solution if you have the facilities to do that, but the prop hub is replaceable . maybe it can be removed cleaned up and refitted.

 

[Alex_Blackwood]

Ah, this sounds likely. So I'm not losing my mind!
Mine is a 4 hp with no reverse gear. I'm reluctant to drill holes to make it fit, so I'm considering a thinner split pin.

If it came off and you haven't touched, or altered, anything it should go back on. I would not even consider drilling extra holes or doing any other "Bodge"
A thinner pin will only rattle around. Seriously look at what you have or haven't done with the dismantling / reassembly. The problem appears to be associated with the drive pin, no?
Cleaning everything up as suggested in #6 may help.

 

[ronsurf]

Another hole drilled at right angles to the original through the shaft for the split pin might be a solution if you have the facilities to do that, but the prop hub is replaceable . maybe it can be removed cleaned up and refitted.
View attachment 184587

Thanks VicS, do you know how that can be dismantled? I did try seeing if the centre came out - there are two slots in part 37 that looked like it should unscrew - I tried it each way and it moved a little but not in a healthy way. I didn't want to break anything. Does it unscrew or do you push it out somehow?

If not I can just about see daylight through the assembly and can get some solid wire through it so a thinner split pin should work. It shouldn't rattle any more than any other split pin, and if it does, I can fit a thicker one.

 

[Refueler]

I assume you have turned prop through 180 deg and then tried again - just in case its a proud spot on the prop ??

 

[ronsurf]

I assume you have turned prop through 180 deg and then tried again - just in case its a proud spot on the prop ??

I have, yes. I spent a remarkable amount of time putting the prop on and off. I've just found a video of a strip down of an Evinrude 4 where the hub came out of the prop and stayed on the shaft. Looked a worse situation than mine.

I might try soaking the prop in hot water then seeing if I can persuade the assembly to separate. Thanks for all your help and comments.

 

[Sandro]

It's a long time I don't dismantle a johnson 4 water pump, but is it necessary to unfit the propellor from the shaft?
Just pulling down the complete foot the pump can be accessed. I can be wrong, though.