OMC COBRA Lower removal

[bruceb58]

Re: OMC COBRA Lower removal

That water plug that you took off the left hand side of the drive is a "no no". I am going to assume you don't have a manual becuase it clearly states never to remove that.

I am not sure what is invloved in getting that retainer back that fell in the drive but you just added a lot more work. That hole is used in the manufacturing process of the drive and is never intended to be removed.

I can get the drive to move aft about 300-400 thousandths jerking it around.

That is a good start...keep on jerking!

 

[rodbolt]

Re: OMC COBRA Lower removal

sounds like the drive shaft is either hung in the coupler or more likly its rusted and stuck in the gimbal bearing. both are fun.

 

[KrisHall]

Re: OMC COBRA Lower removal

Hey Guys,

GRAPEAPE, huff huff, pant pant have a look at this...Ummm I donno if that bearing was supposed to come out with it or not.

Im not worried about the water plug and threaded back plate...that back plate is carbon steel and I got telescopic magnets and mechanical fingers for that...10 minutes tops. I've already fished the back plate out of the drive.

Something tells me I need to beat that bearing off and if that does not work, fire up the gas and put my surgical skills to work. or maybe a cutting wheel on a die grinder.

 

[KrisHall]

Re: OMC COBRA Lower removal

You are right Bruce,

I do not have a manual ... Yet. Got one on order though.

 

[pra100]

Re: OMC COBRA Lower removal

That would be the gimbel bearing.It was not supposed to come out with drive,but better then having to cut shaft to get out.

 

[bruceb58]

Re: OMC COBRA Lower removal

Well...you killed two birds with one stone. Looks like there was water in there. How did the drive oil look?

 

[KrisHall]

Re: OMC COBRA Lower removal

There was no oil in it, although the gears in the topside look pristine...I also rolled the gears around in the lower end in forward and reverse...nice and smooth with no slop.

the exterior crack looks to be in the shifter oil galley.

Now for the bad news...I tore in on that bearing trying to get it off the shaft...basically destroied the bearing down to the shaft race and was not able to beat the race off of it...fired up the torch the did a near perfect job cutting the race off...Key word here is NEAR perfect...I slipped up and popped a slight gouge in the shaft.

Im checking prices now for a new shaft and am considering just filling it with a 6011 rod... no wait that end yolk looks like cast...nirod... and cleaning it up.

I'm still wrestling with the idea...One little voice says lite a rod and forget about it...another says nope Kris with all the work that is going to go into this boat don't chance it and put it back together ONCE.

Did not know there are a couple O-rings under that bearing...and the gouge is right on the edge of the O-ring recess cut into the shaft.

 

[cobra 3.0]

Re: OMC COBRA Lower removal

Check out this site for a drive shaft and parts breakdowns. These folks are Cobra specialists.

http://www.sterndrive.info/omc_help_page.html

 

[KrisHall]

Re: OMC COBRA Lower removal

Thanks,

Been looking that site over...Look like they have all the parts one might need.

Here's a close up of that yolk. After picking the carbon out of the gouge it's deeper than I thought...must have been a slag pool.

 

[olbuddyjack]

Re: OMC COBRA Lower removal

I've never found out for sure what those o-rings are for but my theory is they hold the inner race to the shaft so the shaft doesnt spin inside the race. If thats the case I wouldn't sweat the nick, just clean up the rust, put some new o-rings on and put it back in.

 

[KrisHall]

Re: OMC COBRA Lower removal

Hi guys,

The new shaft arrived last Wednesday out of florida diversifiedmarine.com , and I got a complete freshly rebuilt upper gear case UPS friday for $650 and no core. It is geared for a 350 so I'll drop the prop pitch from 19 to 17.

I've also located a good set of OEM one piece manifolds.

I've noticed a lower gear case cheap on ebay that a guy keeps re-listing. As time and finances allow I'll start grabbing stuff up.