1989 5.8L Omc cobra shifting problems

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nicolasb

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my boat goes into drive from neutral with no problem, but when i want to go into reverse from drive, the throttle has trouble shifting as if something is blocking it from going into reverse, but it goes into gear by force
and it also has trouble going into drive from reverse
i have taken it to my mechanic and he could not fix the problem
i really want to fix this problem
can someone help me with this problem :)
 

a70eliminator

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Re: 1989 5.8L Omc cobra shifting problems

98% of OMC Cobra shifting issues stem from a worn out lower shift cable, a worn out cable cannot be adjusted and shifting problems progress into rounded off clutch dogs and then your drive will start to make banging noises as the clutch teeth begin to skip in and out of gear, so don't let it progress.
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

thanks for the reply, im in the process of getting new cables

does anyone else have any idea, what could be causing this problem
anything at all
please
 

zbnutcase

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Re: 1989 5.8L Omc cobra shifting problems

Is it in a Bayliner? With original control? If so, they are the crappiest controls ever put in a boat, a new quality one makes huge difference! Also the shift bellcrank can corrode and get stiff, making shifting difficult.
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

it is a bayliner boat
i still have the original control in my boat
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

if you have any idea what might be causing the problem, tell me
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

tell me if there is something that i could check for that might be malfunctioning
i need help to find out what's causing this problem
any ideas ?
 

a70eliminator

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Re: 1989 5.8L Omc cobra shifting problems

Tilt your drive up, look up under where the shift cable enters the housing on the starboard side, that's where the cable sheath broke on mine.
The shift problems you describe indicate a bad lower cable. The shift interrupter switch will also cause problems comming out of gear. what is your idle speed? anything over about 650 can cause shifting issues, should be around 550. Not sure if that is the exact spec but you get what I'm saying, too high of idle is no good and will render the shift interrupter about useless.
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

where exactly is the shift interrupter switch located
and how could i check to see if it is causing the problem
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

is the shift interrupt switch number 1 on the diagram below
 

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a70eliminator

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Re: 1989 5.8L Omc cobra shifting problems

It's on the starboard side, it should look just like this, when you make a shift the fork will actuate the switch momentarily, which cuts the engine ignition for a split second. Try to observe the fork as you shift and you'll see it work, the fork has a spring loaded return and should move freely.
 

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Blk-n-Blu

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Re: 1989 5.8L Omc cobra shifting problems

Boy Iam glad I took the time to post the Hastings article.
 

a70eliminator

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Re: 1989 5.8L Omc cobra shifting problems

Yea, there's no magical fix for OMC shift problems, you need to read that article blk-n-blu posted, get yourself an OMC Cobra service manual and begin troubleshooting.
I wish I could say tap your toes 3 times and say there's no...
 

nicolasb

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Re: 1989 5.8L Omc cobra shifting problems

is it possible that the carburetor is causing the problem
 

Gary H NC

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Re: 1989 5.8L Omc cobra shifting problems

is it possible that the carburetor is causing the problem

Nope!

You will REALLY need the OEM service manual to install and adjust the lower shift cable.
The drive needs pulled and everything measured to specs in the manual.This is critical on the Cobra drives.

Email this seller and tell him Gary in NC sent you.Also get the serial numbers off the engine and drive and he will get the exact manual for it.
Best money you will ever spend on that boat..
http://cgi.ebay.com/ebaymotors/1989...Motors_Manuals_Literature&hash=item2eaaf11a51
 

Blk-n-Blu

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Re: 1989 5.8L Omc cobra shifting problems

Sometimes you give em what they need and they just dont listen. If you dont take the advise given to you just go away
 

Blk-n-Blu

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Re: 1989 5.8L Omc cobra shifting problems

You just can't help some people!!
 

Gary H NC

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Re: 1989 5.8L Omc cobra shifting problems

You just can't help some people!!

Agree,
I have done many Cobra shift cables and if not done to specs it will never shift right and end up being a destroyed lower...:rolleyes:

If they would post where the heck they are there may just be someone with Cobra experience to help out...:(
 
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