Say 'no' to crack: why did this happen?

[tsheie]

Prepping the boat for spring launch, and going up and down the ladder, I noticed a little oil/lube seepage from somewhere near the prop.. and discovered a crack running up one side of the prop housing (1998 Nissan 9.9 D2 2 cycle) and over to the other side.. The housing around the bottom bolt is intact. Why would this occur? The motor was winterized and stored in a garage, it wasn't dropped, we didn't hit any objects while underway (the rudder would have taken the hit first).. This has been a wonderful, reliable motor for almost 12 years.. Ideas as to why this might have cracked?

 

[Deadline]

Alingment out?

Perhaps the differential was out of alignment to the point that it cracked the housing. But you would have noticed it in shimmying.

Regardless, you win the Best Head Award of the year for this site. Good luck.

 

[finding41]

Looks like an easy fix. You might be able to find parts here.
http://www.maxrules.com/fixnissanindex.html
Say no to drugs kids.

 

[Rich Stidger]

When you winterized did you drain and refill the lower unit and verify that there was no water in the oil?

If that was done, I would just replace the part and write it off as unknown. But I would keep an eye on the new part.

 

[tsheie]

Rich, I had the same first thought, but when I winterized it, I noticed there was a little milky/cloudiness to the gear lube--a little water was getting in through the crack, I think. Yes, we'll chalk this up to 'unknown', and pay close attention..

 

[sailaway78]

I'd bet a beer

That when you pull the prop, you will find some monofilament fishing line wound up in there.

 

[tsheie]

Re: I'd bet a beer

I think I'm going to win a beer.. Mono line? Lake Superior? Doubtful...but we'll see! (Good ideas--I knew the community would come up with something!)

 

[FourPoints]

I'm going to jump in and hijack the thread for a second, if you decide to scrap the engine for any reason down the road, let me know. I have the 8hp model and I would love to acquire a 9.9 parts engine...