I am thinking I need a new out drive what do you think?

Geno 19

New Member
Jun 15, 2014
3
United States
Boat Info
1991 Sea Ray Overnighter
Engines
Mercruiser 6 cyl
Cruising along fine in my 20 ft 91 Sea Ray at about 50-75% throttle and everything is fine. I hear a loud bang. I throttle down quickly. When I put it back into gear engine runs fine but the prop wont spin in forward or reverse. No visible damage to the outdrive and didn't see anything in the water. Do you think I hit something submerged or did the outdrive just go up? I guess it doesn't matter I am just curious
 
Hopefully you hit something and spun a hub. New prop is way cheaper than a new out drive.
 
If it is not a spun hub, and I hate to say, it sounds like it isn't - hubs don't typically fail with a loud bang - it's likely you broke the vertical drive shaft in the outdrive, assuming this is an alpha one drive. If this is the case, you need to be very careful, and don't run the engine for long periods until you know what was damaged. This shaft passes through the water pump, and drives it. So, if it is broken, you are not pumping water when the engine is running, and you risk an overheating situation.

Pull the boat - it's coming out anyway - and find out what is broken. If it is the vertical shaft, you will only need a lower housing rebuild, or a new lower housing. Usually, there is a piece of the shaft still stuck in the upper housing, and you need to carefully remove that before the drive can be re-assembled.

Good luck with it, and let us know how it goes.

Dale
 
Dale could potentially be right, but I'm an optimist. If there was minimal damage to the prop, those hubs are designed to give first as they are plastic. Pull the prop and hub first as it is the easy check. If the hub is in good condition, then you can allow your blood pressure to rise at that time.
 
my vote is for a stripped gear in the upper unit.....you can remove the square cover on top of the drive to see the upper gear.....i'll bet you have stripped that gear.....
that is why i switched to an aluminum prop....the stainless props are so rigid that if/when you hit something with them the shock through the driveline can be enough to strip this gear.....ask me how i know....

good luck....

cliff
 
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Thanks for all of the replies. The boat is pulled and I am waiting on the verdict from my mechanic. I am guessing its not going to be good. While it is possible I hit something I don't think so. I was in 8ft of water and I was paying close attention and there is zero visible damage to the prop. If hit something it was definitely submerged. I didn't really feel anything with the boat other than hearing the loud bang. If nothing else this experience made getting tow insurance a top priority. I will post the verdict when it is in but I am thinking it is not going to be good. Any idea what an out drive on this type of boat will cost?
 
Thanks for following up. If there was no visible damage then that's not a good sign. A new mercury lower unit retails for about $2500 but I see used ones on craigslist for between $300 and $1500 depending on condition. Another option would be stern drive engineering. SEI makes replacement lowers and complete drives for much less than a new mercruiser. They also have a good reputation for honoring their Warranty.

Good luck, I hope you get back on the water soon without too much out of pocket.
 
I agree with Dale. If it was a spun hub on a prop, you'd also see damage on the prop to force that to fail. If it is the vertical shaft or something similar, it's repairable, not cheap, but not life ending either. Good luck and hopefully the whole drive didn't grenade.
 
I have physical proof that a plastic hub can survive a prop strike. I hit hard bottom last year, and it took an entire blade off my aluminum prop, but didn't spin the plastic hub. So much for those hubs giving up the ghost to save the prop. :smt013

That has happened to me too. But when I have hit with a stainless prop both times the hub spun and there was no noticeable damage to my drive. They are designed to protect the gears, not the prop. When my laser 2 hit the anchor one time long ago it had the old hub. Trashed the lower completely, twisting splines on the gears.
 
The verdict is in: engine coupler and some minor residual damage.

Ouch!....engine has to come out for that repair....great time to clean the bilge and check out other 'stuff' not normally accessible when the engine is in place.....

good luck.....

cliff
 

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