OMC Cobra Slipping Under Load

[TroyHogsett]

Okay guys/gals I need some advice. Sorry this is a long post, but I thought I should give some background. I have a 4.3L/cobra outdrive combo, that has slipped under load twice now. I had the upper gear case replaced in 2001, which costs me $2000. The lower was cleaned and resealed. Now the same shop is telling me it could run another $1200. The boat is old (1988) and the interior is getting ratty, so I hate to sink another grand into it. I do not "Grandma" it into gear, and I mantain/winterize it methodically. My questions are these: how many of you guys have done the clutch dog replacement yourself? How many were successful? How much do the parts cost? I have the OMC manual, but no specialty tools. I am a country boy/redneck and pretty mechanically inclined. I just finished putting a blower on my chopper, but I have never dove into the outdrive. Is it terribly complicated?

 

[WillyBWright]

Re: OMC Cobra Slipping Under Load

Welcome to iboats. <br /><br />I doubt it's in the drive. They're either in gear or not. Slipping is possible at the prop hub or the engine coupler. That's where you should look for slippage. The prop hub is an easy one, just have it repaired or replace the prop. For the engine coupler, you have to pull the motor. They usually stink like burning rubber back in the engine compartment, especially towards the back.

 

[TroyHogsett]

Re: OMC Cobra Slipping Under Load

Thanks for the welcome Willy. It happened while I was pulling a skier. It sounded like I hit something with the boat, but I didn't. It happened again while I was getting on plane pulling a tube. It sounds like a real hard "thunk" and then it goes right back to pulling. <br /><br />How do I check the prop hub? Just pull the prop and look at the rubber insert?<br /><br />Thanks for the reply.

 

[Boatin Bob]

Re: OMC Cobra Slipping Under Load

Hard to see it on the prop but what you can do is scribe a line across the hub to the prop and put it back on. Next time you have the problem look to see if the lines don't line up anymore, then take the prop in and get a new hub put in.

 

[TroyHogsett]

Re: OMC Cobra Slipping Under Load

Thanks Bob,<br /><br />Does it matter that I can not make it slip by manually turning it out of the water?<br /><br />I tried it just a while ago, and can turn the prop but it seems like everything is turning with it.<br /><br />What else could it be?

 

[marunr]

Re: OMC Cobra Slipping Under Load

Originally posted by choc:<br /> Thanks for the welcome Willy. It happened while I was pulling a skier. It sounded like I hit something with the boat, but I didn't. It happened again while I was getting on plane pulling a tube. It sounds like a real hard "thunk" and then it goes right back to pulling. <br /><br />How do I check the prop hub? Just pull the prop and look at the rubber insert?<br /><br />Thanks for the reply.

Sorry, but it sounds like the gears to me. When my OMC gears went bad, it sounded like the ski rope grabbed after getting to the end of 20 feet of slack, or like someone hit the drive with a bat. It started off only doing it upon acceleration, then got to where it would constantly happen while driving at any decent speed...almost every minute or so. I had my gears replaced about 8 years ago, and fortunately I came across i-boats website a couple of years ago and started adjusting my cables using this:http://www.funkopolis.com:8080/~stuart/cobra/<br /><br />I hope I'm wrong. I had the shop do my gear replacement. About 8 years ago, it was around $750<br />Even if you do the work yourself I think the gear sets are still pretty expensive. Good luck!

 

[TroyHogsett]

Re: OMC Cobra Slipping Under Load

Thanks Marunr<br /><br />I think it is the gears/clutch dog surface that is slipping. My cobra is a 1988 model, and the OMC guy that is working on it says they are weak. The gears cost 523.00, seals 40.00, he says it will run 8 hours probably on labor, which with tax is going to kill 1200.00<br />Does this sound right? He told me "You really don't want to try and fix it" without the tools, he is probably right. He is the only OMC guy in our area.<br />In 2001 I paid him 2000 for a complete upper. ARGH<br />Please keep telling me this boating thing is fun. My kids sure think so.<br /><br />Troy

 

[marunr]

Re: OMC Cobra Slipping Under Load

I would think that's about right. Look over the link I posted and make sure he's adjusting the cables properly. You could buy a manual which would list the tools you need. I don't have mine handy so I can't tell you right off.<br /><br />Mine is also a 1988 model and I'm starting to have a number of things that need attention and will take some of the "fun" out of it I think. But for 15 years, it's been a great boat. People always say, "well, you got your moneys worth out of it",and maybe I have, but I hope it lasts a lot longer every time I look at new boat prices!<br /><br />Good luck!<br /><br />I should say, I don't know about the labor. Maybe one of the pros around here could tell you, but it would take ME a lot longer than that!