an unhappy impeller with pics!

[OMCboater]

Woo! I think I dodged a bullet on this one - thanks to iboats. Getting ready to put my I/O into the water after 2 years of replacing stringers/transom/floor/motor mounts. Started it with the leg in water but didn't get any water up to the engine (didn't run long at all). Had read enough on iboats with advice to replace impeller regularly and decided to go ahead and do it - not an easy task on omc - have to remove leg, separate upper/lower case. Anyway, here is what I found

I cannot imagine how that housing broke inward toward the impeller - there is a screen over the water intake that would not allow anything bigger than sand to come through. I have the new impeller and housing and it will be put back together today. Still hoping to be in the water by Sunday.

The clymer manual I have is *&%^^$#!!! but I think most of you already know that. For assembly of the impeller, it states to seat it in by turning counterclockwise, but the picture clearly shows the impeller vanes bent over from a clockwise rotation. Does anyone have the proper orientation to turn the impeller when seating it in the housing on a 69 OMC 120?

 

[wire2]

Re: an unhappy impeller with pics!

Logically, the input ball gear turns CW, (same as a standard engine). The bevel gears in the upper housing transmit power in the same direction, (CW looking down) to the shaft holding the impeller. But, when you mount it under the upper gear housing, you are looking up, so it will be CCW . You have to take into account which way the camera is pointed.

I expect that pump housing may have had water in it which froze one time, breaking the casting.

 

[KaGee]

Re: an unhappy impeller with pics!

You wouldn't have got far on that!

Put a complete water pump kit into it... Don't just replace the impeller.

Make sure you clean the splines up good an cover them with the triple guard grease or an equivalent.

 

[OMCboater]

Re: an unhappy impeller with pics!

Thanks for the tips. the water and freezing prob makes the most sense as I know it sat neglected for a number of years before I got it. I know the PO and I highly doubt it was abused in any way, but it did just sit and was not properly covered.

I do have the complete pump kit and I have a homebuilt sandblast cabinet that I used to clean up the shaft (only used glass beads!!)

 

[whywhyzed]

Re: an unhappy impeller with pics!

the impeller hsg broke like that because someone has stored the drive tilted up over the winter without the water drained out of the leg.

 

[WaterWitch2]

Re: an unhappy impeller with pics!

I don't know if it's the camera angle or just me, but the splines don't look quite right in your last picture.

 

[OMCboater]

Re: an unhappy impeller with pics!

I don't know if it's the camera angle or just me, but the splines don't look quite right in your last picture.

you are correct. the splines are a bit skewed. I agonized last night about whether or not that was a problem and decided that it shouldn't be (unless I can source a new one in the next couple of days) - the full length that is splined into the driveshaft is straight.

If it was just a matter of running down to the boat place and picking one up, I would get a new one in a hearbeat, but I suspect new ones are probably now made of unobtainium

 

[wire2]

Re: an unhappy impeller with pics!

Here's a possible Canadian source for parts;
http://www.boatparts.ca/id10.html

 

[OMCboater]

Re: an unhappy impeller with pics!

what do you think about using that old shaft as is? I would think the only risk is that it would twist right off and that doesn't seem very likely to happen. I am curious as to what would cause that twisting though...

 

[wire2]

Re: an unhappy impeller with pics!

I expect that offset is the result of a hard impact between the prop and a rock or log. Any serious marks on the skeg?

 

[OMCboater]

Re: an unhappy impeller with pics!

I expect that offset is the result of a hard impact between the prop and a rock or log. Any serious marks on the skeg?

I gave the skeg a once over and don't recall seeing anything major but will look again. the inside doesn't appear to have any other major issues - all bearings are tight and seals are sealing so....looks like I might be in the water by Sunday. (fingers crossed).

I am going to reuse that shaft for the rest of this season and then totally rebuild the leg over the winter. the new shaft can be had for $150 Can and I just want to put enough $$ into it for now to do some test runs and make sure it is overall worth keeping.

 

[Lyndy]

Re: an unhappy impeller with pics!

I don't know if it's the camera angle or just me, but the splines don't look quite right in your last picture.

Same problem when I looked at it. Not sure if you should try to use it or not. Looks like you are going to try anyway. Best of Crossed Fingers!

Not sure if that impeller melted or just blew up! HeHeHe. What a mess

 

[OMCboater]

Re: an unhappy impeller with pics!

Looked at the skeg again - it is 38 yrs old and shows it, but nothing that would indicate it ever got really hammered.
I put it back together last night with a new impeller and housing. Going to put the leg back on tonight and hit the water this weekend, for the first time since I got this boat a couple years ago. If no one ever hears from me again....well......

regarding the mess of the impeller - best guess is that the PO stored it with the leg up and it filled with water, then froze and the housing cracked into the pump. shortly before selling to me he had started it up for the first time in years and I suspect the impeller destroyed itself on the cracked housing at that time.

 

[Mike V]

Re: an unhappy impeller with pics!

Good Luck & Enjoy!