No oil in upper unit OMC Cobra

Ok fellow boaters. I am fairly new to being a boat owner and try to do small repairs myself. In fact, I changed the oil in my upper and lower unit myself (so I thought). I was told to remove the lower plug and then the middle plug to let the oil drain. I let it drip dry for about 2 hours. Once the unit was drained, I filled it from the bottom with my pump until oil came out the middle plug. I then sealed it all back up. A few days later, I took the boat out and ran it for about 5 minutes when I started hearing a howling noise coming from the outdrive area. I turned the boat around and trailered it back up. When I got home, I pulled the top cover off the outdrive (where the oil dipstick is) to find the upper gear case bone dry of oil. I thought the upper unit was separate from the lower unit and they had to be filled separately. Apparently I made a costly mistake.

After I realized there was no oil in the upper unit, I pulled out my Seloc manual and realized you are supposed to fill from the middle plug which fills both the lower AND upper unit at the same time. You then check the level with the dip stick. Duh, this makes total sense now.

When I look inside the gear case where the two gears are, I notice quite a bit of metallic dust on the sidewalls and the bearings. Upon inspecting the gears themselves, they are visibly worn. There aren't any big chucks missing, but they are definitely worn a bit.

My question is this: Can I still run the boat like this if I fill the upper gear case with oil? They obviously need to be replaced, but are they salvageable for awhile? My guess is no because of the metallic dust everywhere which will eventually wear the gears and bearings out completely. Thoughts???

Ayuh,..... If you can "See" wear on the gears, they're Junk, 'n won't run more than a few hours til they're completely dust,......

What have you got to lose? Flush it out with some solvent, refill it with oil, and use it. Whether it lasts minutes, hours, or years will be dependent on how much damage was done. Just don't go anywhere you can't be towed back from

I guess my biggest concern is will it do damage to gears in the lower unit if not fixed? What type of solvent would you flush it with? I'm thinking I should just have it fixed right and not have to worry about it. Unbelievable how much these gears cost!

Hi Decker. You didn't fill the leg correctly. You are supposed to fill it from the middle hole not the bottom and that's why you effed it up your drive. It takes 64oz of oil and you check the dipstick after you fill it to make sure. You had dry gears up top (air bubble). How much oil did you put in it? Hopefully you can flush it and fill it properly and still get some use out of it. Sorry this happened to you man!

Edit: I see you figured out your mistake after the fact. Good luck and let us know what you end up doing and how it goes. Yeah those gears are super expensive. I think I'd be looking at a merc conversion if you have to spend too much on the cobra.

Not quite sure how many ounces I put in. I just filled it from the bottom until it came out the middle hole. So I'm hoping the lower unit has enough oil in it. There aren't any big chunks missing out of the gears, but you can see wear on them and there is quite a bit of metallic film inside the upper gear case. A real fine dust. Reference flushing the leg, how would you flush it. Can I fill it with diesel, engage the prop for a few seconds and then drain it? Do that a few times maybe and then refill the leg properly?

Once you get metal flakes in the oil you are pretty much done. It has gotten into every rotating surface and destroyed it. So your only recourse at present is to tear the upper gears apart, replace all the bearings and gears and start all over. I would start looking for good used complete upper, which will be way less money than buying a new upper gear set.
http://www.ebay.com/itm/Nice-Used-O...ter-/271877092896?hash=item3f4d233620&vxp=mtr
http://www.ebay.com/itm/OMC-Cobra-1...065-/261729425764?hash=item3cf04a1964&vxp=mtr

Is it likely the lower unit is shot too from the metal coming from the upper unit? There was no oil in the upper unit so I wouldn't think the metallic pieces would have a way to get to the lower unit. I'm afraid if I flush it, fill it up with oil, and run it, that any metal pieces that may be left behind would eventually travel to the lower unit and destroy that too. Should the upper and lower units both be replaced during incidents like this?

Perfect opportunity to switch to Volvo Penta.
It needs a complete teardown and overhaul. It is difficult to justify that expanse on an OMC drive. Take out a second mortgage and get a duoprop drive.

I wish one of those upper units you provided a link for would work. Not bad prices. Unfortunately I have the V6 with 21:19 gears. I'm not gonna spend a fortune on this boat. I'm gonna try flushing it a few times with diesel and then refilling it with oil the RIGHT way. I shall see how long it gets me. There aren't any chunks or chips missing out of the gears, just visibly worn and lots of metallic dust in the reservoir. Hopefully I can get the rest of the year out of it. It's unfortunate as this boat only has 87 original hours on the meter.