OMC Cobra Noise from outdrive

dwfish77

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Joined
Aug 11, 2005
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12
I have an '89 Four Winns with a 5.0L and Cobra drive. Only twice in one day did I hear a noise that sounded like hitting bottom while trying to get on plane. Haven't heard it again, but I'm wondering if I shouuld be concerned. The water was about 20' deep, confirmed with 2 depth finders. It happened in 2 different locations so I doubt it was something under water. Also, no damage to outdrive or prop.
 

marunr

Petty Officer 1st Class
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Jul 11, 2004
Messages
225
Re: OMC Cobra Noise from outdrive

Hi,
You need to read this site carefully if you haven't already.
http://www.hastings.org/~stuart/cobra/
(copy and paste...this isn't rendering correctly)
The noise is the clutch dog and you are on your way to losing your gears if you don't get it fixed right away. There's a lot of info at this site so print it out and get your manual out. It will only get worse, and quickly.
Sorry!
 

dwfish77

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Aug 11, 2005
Messages
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Re: OMC Cobra Noise from outdrive

I thought the previous owner said this service was performed a while ago. Do you think this is something that can come out of adjustment again? Also, does this mean the clutch dog might be damaged already or the cable needs adjustment to keep it from being damaged?

thanks for all the info.
 

Don S

Honorary Moderator Emeritus
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Aug 31, 2004
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62,321
Re: OMC Cobra Noise from outdrive

They don't just come out of adjustment. When they do, it means something is worn out. Usually the cable.
 

marunr

Petty Officer 1st Class
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Jul 11, 2004
Messages
225
Re: OMC Cobra Noise from outdrive

I check the adjustment every year when I pull the outdrive for servicing. I missed a bad place on the bellows this time however, and got water in my drive last weekend. In my case I think that is what caused mine to slip since i had water around the shifting mechanism, resulting in increased resistance to the shift cable. I knew about the problem because of the very thing you describe...the "clunk". After one time, I pulled my boat out of the water. So, I think we're both in the same situation. I'm replacing my bellows and readjusting everything and hoping for the best, since the alternative is more $$$ than my whole boat is worth (at least in money. It's worth a lot more than that to me)

I've had my lower unit gears replaced before, for about $800, but that was back when OMC was still in business.

Since I had no sign of any metal on the lower drain plug magnet I'm hopeful. Good luck to you. You could always take it in and have someone check the clutch dog if you want to be sure. Not sure what that would cost...could be pricey.
 

dwfish77

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Aug 11, 2005
Messages
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Re: OMC Cobra Noise from outdrive

I want to add to my original post. I was in a hurry when I wrote it. I removed the engine this spring to fix a seal leak in the y-pipe. I unplugged all wires but unbolted the shift cable bracket instead of removing cables. Is that a possible cause or could it be in the outdrive part from removing that? Also, is there any way of determining if the cable is bad?

Thanks, this has been great info and is helping learn more since this is my first boat. I will be taking it out of the water tonight and hope to fix over the weekend.
 

dwfish77

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Aug 11, 2005
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Re: OMC Cobra Noise from outdrive

Does anyone know if the shift cable needs to be replaced, does the engine need to come out?
 

marunr

Petty Officer 1st Class
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Jul 11, 2004
Messages
225
Re: OMC Cobra Noise from outdrive

The engine shouldn't have to come out to replace the cable. Do you have a manual? The hastings site I posted earlier says there should be no more than 2-1/2 lbs resistance using a sping scale on the cable...either direction.

I'll bet you're out of adjustment since you pulled the engine. It also could be that the previous owner didn't adjust it properly when he serviced it. The measurements are critical.
 

dwfish77

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Joined
Aug 11, 2005
Messages
12
Re: OMC Cobra Noise from outdrive

I didn't think just unbolting the entire bracket would change anything, but maybe i knocked the other end installing the outdrive. You never know, but what I do know is, it needs to be fixed so that's where I'll start.
 

MrPink

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May 7, 2006
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Re: OMC Cobra Noise from outdrive

I've been there buddy. I had to have the bottom gears replaced1200($). Do you get the sound right when you come up on plain? My problem was the shift cables were not adjusted correctly.
 

dwfish77

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Aug 11, 2005
Messages
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Re: OMC Cobra Noise from outdrive

Yep! How long did you notice the problem? I only heard 3 times which was to get me back to the slip. I'm hoping I can adjust the cables and not have to replace the gears.
 

dwfish77

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Joined
Aug 11, 2005
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Re: OMC Cobra Noise from outdrive

Well, have the boat at home now. Checked the fluid and was a creamy brown color very slight metal shavings in it. Almost looked like metallic paint in regards to the size of the particles. Any suggestions? I'm wondering if the shift cable is actually ok and water is my issue or could one problem caused the other problem? This all boggles my mind because the boat only has 160 hours on it?
 
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