Cobra Stern Drive Taking On Water

[Durangomania]

I have an 89 Four Winns 180 Horizon with a Cobra Stern Drive-V8. Suddenly started getting water in the bildge whether engine is running or not. No exhaust manifold or engine leaks, hull is prestine. Water is coming in somehow thru the stern drive. About 2 gallons per hour when moving slow or anchored without engine running. PLEASE HELP!

 

[tylerin]

Re: Cobra Stern Drive Taking On Water

You might want to check the bellows (black ribbed hose, maybe 4 inches in diameter). Your spline shaft, u-jonts run through these bellows. If this is the problem, don't run it any more til you get it fixed. You will create bigger problems. There are two of these bellows going from drive to housing, its the upper one

 

[CCrew]

Re: Cobra Stern Drive Taking On Water

I'd concur with tylerin on the bellows. If indeed it is the bellows, be prepared to replace the gimbal bearing and the U-Joints as they've been subjected to water, and it's not a question if "if" they'll fail, but "when". You're looking at about $90 for the transom bellows kit, $70 for u-joints, and $35 for the gimbal in parts, then the labor to install. It's a pretty straightforward repair. Only special tool required would be a slide puller for the gimbal bearing. <br /><br />Regards,<br />Roger

 

[Durangomania]

Re: Cobra Stern Drive Taking On Water

Thanks for the input so far. I just had the u-joint greased, work order says NO WATER IN THE BELLOW. Could they have damaged it on re-assembly. I'm not exactly sure when the water started, if it was before the u-joint greasing or after. Any other option(s) that could cause the problem? Thanks much for all input ! Ray

 

[RSErspamer]

Re: Cobra Stern Drive Taking On Water

Check out the shift cable bellows ends and make sure they have the clamps or tie wraps on them.

 

[andrewgroup]

Re: Cobra Stern Drive Taking On Water

Worst case scenario is the trasom plate seal is leaking allowing water to leak up and into the bilge from behind the transom plate.<br /><br />In my case, this was caused by a boat that sat for two seasons and the drain hole became clogged with debri and water built up in and around the drain hole. This water was absorbed into the plywood transom center and softened the wood. This softening allowed the two lower bolts on the transom plate to weaken and became an entry point for water.<br /><br />Diagnosing this was two-fold. I mounted a small video camera under the engine and pointed it up and to the inside of the transom from under the motor. When in reverse it leaked more than when it was in forward. The reverse gear helped pull the transom plate from the back of the transom allowing more water to leak in.<br /><br />I also did stuff like I wrapped the bellows with Saran Wrap from the kitchen to eliminate bellows leaks from cracks in the bellows, Backed the boat into the lake keeping it strapped to the trailer to apply more water pressure.<br /><br />If the obvious stuff like driveshaft bellows or shift bellows isn't the problem then get in touch with me about the options to fix the worst case scenario. Hopefully it's just bellows...

 

[Durangomania]

Re: Cobra Stern Drive Taking On Water

Thanks for all the great input guys, this board & forum is great! I tend to think it is the drive shaft bellow. The boat is nearly 15 years old and they are the original bellows. When I took a closer look at the exhaust bellow, it has a lot of stress cracking in the inside ribs. There must be a leak in the drive shaft bellow that I can't see. Sounds like a good winter project to fix it. Ray

 

[tylerin]

Re: Cobra Stern Drive Taking On Water

Durangomania, Don't worry to much about the exhaust bellows, as a matter a fact the replacement will come with slits (holes) in it. Be concerned about the upper and the damage (if its bad) it caused..... u-joints, gimbal bearing like CCrew mentioned. Easy drive to r&r

 

[Durangomania]

Re: Cobra Stern Drive Taking On Water

Does anyone have any idea what the total cost would be to replace the Exhaust Bellow, Drive Shaft Bellow, Gimbel Bearing & Seal and U-Joint?<br />Looks like I am heading that direction.

 

[CCrew]

Re: Cobra Stern Drive Taking On Water

I posted the parts prices in a previous post. I'd figure on $300 labor and $200 parts and that should put you pretty close. None of it's hard if you're fairly handy mechanically. <br /><br />-Roger

 

[Durangomania]

Re: Cobra Stern Drive Taking On Water

Hi, thanks for all input. I have a Clymers repair manual, replacing the belllows looks fairly easy. The manual shows a clamp on the gimbel side of the drive shaft bellow, how does it attach at the stern drive side?

 

[rino]

Re: Cobra Stern Drive Taking On Water

I have a '76 OMC stringer 190 HP Ford with a leaky transom seal. I confirmed it was the transom seal; it's pretty obvious that it has a small leak.<br /><br />The screws around the top of the seal show some wear (probably very old).<br /><br />How much of a job is it to replace this seal?<br /><br />Do I have to remove the outdrive from the engine or can I remove the boot without removing the outdrive? If I have never removed the outdrive before but some mild mechanical skill, how long should it take and what special tools do I need?<br /><br />I have a Clymer OMC Sterndrive shop manual for 1964-1986 and it only has one sentence about removing the seal.

 

[pra51]

Re: Cobra Stern Drive Taking On Water

I took my cobra drive off and removed the bellows.The way mine was attached was,on the side to the drive it had a big spring retainer inside it that held it in a grove,you will see this when you pull drive off.On the end closest to transum it has a big stainless steel screw clamp.By the way,it isn't hard pulling cobra drive.I lowered the bow of boat down so the stern is higher.I lowered the drive down so the skegg set on a piece of plywood.Follow book on removal,pull and wiggle drive and it will slide out.I did mine by myself,figure it weighs about 90 to 100 pounds,I was able to pick mine up and care it.I built me a frame out of 2x4s with rollers under it and set drive in it and rolled it away.Follow the manual and it isn't a hard job.Also the exhaust bellows as stated above, that you buy will have slots in it along the bottom,which might make you think it is defective.That is how they make them now.Hope that helps some.

 

[rino]

Re: Cobra Stern Drive Taking On Water

So, did this with the boat in the water?<br /><br />My outdrive is an OMC stringer, so it's a little different. A different post said they did it with the outdrive on, but it was a bit of a pain (easier than pulling the outdrive). Do I have to align a Stringer outdrive or is that a Merc thing? Is there a coupler or gimbal to worry about? Like I said, my OMC manual isn't that clear. I saw a '74 manual on eBay but I doubt it's worth $20 to buy a '74 manual when I have a '76 (or is it much different?)<br /><br />If I could do it in the water it might save me $260 to haul out a 26' boat plus labor. <br /><br />If this is at all possible, maybe I should try pumping up my inflatable under the back of the boat for extra lift. I might be able to borrow a trailer if I can get the job done in a few hours.

 

[Bondo]

Re: Cobra Stern Drive Taking On Water

rino,<br />NO, No Way It'll get done In the Water....<br />Unless you intend to Sink the boat.....

 

[rino]

Re: Cobra Stern Drive Taking On Water

I figured it had to be out of the water. Is this somebody that can be done in a couple hours with a power screwdriver and a few basic tools by somebody with basic mechanic skills... or do I need any special tools?<br /><br />From some other posts it looks like this can be done without pulling the outdrive off the engine with a little extra effort.<br /><br />Looking from both sides of the boat I don't see an aluminum plate, so could I be on the wrong base here?<br /><br />What other service should I try to do while the boat is out?<br /><br />Change lower unit lube, inspect impeller? What else should be checked while it's dry?

 

[tylerin]

Re: Cobra Stern Drive Taking On Water

Rino, You really need to start a new post about your questions. This is Durangomania's post about a Cobra outdrive. You'll get much better results, not to mention you shouldn't do that to Durangomania. If you're gonna check the Gimbal and impeller you're gonna need to pull the outdrive. Find yourself a better manual that explains exactly what you need to do to repair your seal. DON'T rush this job, plan on having her out for a few days at least and do all neccesary maintenence to the outdrive.