Broken bolt on lower unit...still safe?

[Billy5000]

I was doing a once over on a boat I got last year. Everything made it through the winter and it started and ran well. But I noticed a bolt holding the lower and upper half of the outdrive housing was missing. I took a closer look and found the head was snapped. Ugh. Extraction would take a lot of elbow grease, but....if three bolts and 90% of the fourth is sufficient for operating, I will probably wait to repair the bolt until the lower unit needs to be opened. Figured I’d ask you guys what you think. Thanks!

 

[Scott Danforth]

drop the lower, fix the broken bolt, fix the corrosion, and while at it, change the impeller.

if 3 bolts would be enough, that is what would have been there from day one from the factory.

 

[Billy5000]

Looks like I got something to work on. Any tips on how to extract that bolt? Access is tough because of that lower half.

 

[Chris1956]

After you drop the gearcase, if you have some luck, the tip of the bolt will be sticking out. Put some penetrating oil on the stud, and use a good pair of vice grips to turn it out. You need to find the source of the corrosion, as what you have is not normal. I expect some sort of electrical leak into the water. Also, replace the other bolts.

 

[gm280]

Good advice from the above comments. I would also tap the holes before putting any new bolts back in any of them. It will help keep them cleaned out as well. JMHO

 

[glust]

As well as new bolts I think I would chase the threads as well. You aren't cutting new threads so a cheaper die tap will suffice. You are just chasing out corrosion,

 

[Captain Caveman]

I'll be the devil's advocate for a moment. You could probably run that in the lake a few times, but each time is a risk. When I'm buying motors I take my queues from the condition of the equipment. The prior owner probably didn't want to deal with the problem....and who knows for how long. Whomever said to change the impeller was spot on. I wouldn't believe the prior owner for two seconds. You need to get that thing off and fixed.

 

[BTL]

Last year I cracked a housing due to lost bolts. That wasn't a fun repair.

 

[jimmbo]

Scott is correct, "if 3 bolts would be enough, that is what would have been there from day one from the factory."

However, you won't find the water pump by dropping the gearcase. That is a Volvo drive, the Raw Water pump is either in front of the Harmonic Balancer, or on a bracket and belt driven

Also the previous owner painted the outdrive and in doing so painted the large Anode that is forward and upward of where you drew the red circle. You need to remove the anode, clean the paint off and reinstall it ensuring it has a good electrical connection to the housing