OMC Cobra Not Shifting Right

[launboy]

Maybe this topic has been posted before, but I couldn't find it in the quick search I did.

Ok, I don't know all of the specifics as I'm posting this for a friend about his boat, but I'll try to get as much info as I can.

He has a Four Winns Horizon 200, with an OMC Cobra I/O. It's a 6 cylinder engine with a black Cobra outdrive. Last summer I was out with him and when he shifted, it wouldn't go into gear right away. He had to rev the engine some and then you would hear a very noticable "THUD" and it would go into gear. He said it had never done that before. We were on a fishing trip for his son, and it started doing it after the second or third time we stopped, and continued throughout the rest of the day.

He said he had changed the outdrive oil the day before and it didn't have any metal shivings in it.

Anyone have a clue to what the problem might be? I doubt it's something good.

Thanks,
Adam

 

[Don S]

Re: OMC Cobra Not Shifting Right

He said he had changed the outdrive oil the day before and it didn't have any metal shivings in it.

If he did the refill improperly, he has less than half the gear lube necessary for the drive.
Drain (look for metal in the oil) and see how much was in the drive.

High idle rpm will also cause a thud when putting into gear, Popping out of gear because of a bad lower shift cable or impropely adjusted shift cable can cause it to pop in and out of gear.

 

[launboy]

Re: OMC Cobra Not Shifting Right

The high idle causing a thud would make sense, since the boat wasn't idling when it dropped into gear. He actually had to give it some gas and rev the ngine a bit and when he would give it some gas, it would drop into gear with a loud thud, and off we would go. I know that can't be a good thing for an outdrive.

Also, I'd be surprised if he didn't fill the oil properly, he has done it before and has read up on the information on how to do the simple maintainance stuff.

I figured if I put that he changed the oil, that would be one of the things people would come up with as a problem, but assuming that part is right, what else would cause it to need to be revved to get it to shift?

Thanks,
Adam

 

[HT32BSX115]

Re: OMC Cobra Not Shifting Right

Howdy,

It is extremely important that he did fill the drive correctly. There is a drain port (at the bottom) and a fill port (the middle one)

If he didn't fill it correctly it wouldn't have made it very far around the lake once in gear. The upper gears are out of the oil if that happens and they get very hot very fast.


What year model is it?

In any case, lower shift cable binding/adjustment, shift plate adjustment etc is usually the cause.

Depending on the year, there may be a "Shift Assist module" , micros-witches that operate it or the linkage that could be defective or out of adjustment.

If you or he wants to and are able to fix it you REALLY need a correct year, OEM manual. If it's an older (clutch-dog style) Cobra prior to about 93 or so it would be helpful to have a look at the "Stuart Hastings Cobra" article. (just do a search of those 3 words to find it)

A binding lower shift cable sounds like what's happening since pushing the throttle forward moves the shift cable before moving the actual throttle.

If the shift cable doesn't move enough to put it into gear you wouldn't have to move the handle much more to start moving the actual throttle cable. The RPM would rise before the shift cable would finally (and abruptly) move......causing it to go into gear at a much higher than idle RPM...

If this is actually happening. It won't be long before the shift dogs (or cone clutch) are damaged.
It needs to be fixed. immediately.


Regards,


Rick

 

[launboy]

Re: OMC Cobra Not Shifting Right

I know the boat is older then '93. I'm pretty sure it's an '89, or at least, something in the '85-'89 area.

If you say the boat wouldn't have made it around the lake without the oil filled properly, then I doubt that's it because we were all over Lake Geneva, Wisconsin that day and didn't have any problems other then the loud thud.

That was summer '06, and I don't even know if he's taken the boat out since then. I'll find out tomorrow if they've used it since then and if the problem has gotten any worse. I'll also try to get a conformation on the year.

Adam

 

[HT32BSX115]

Re: OMC Cobra Not Shifting Right

If it's that old it IS a "Dog-clutch" style Cobra. All the more reason to ensure that it's got a good shift cable and/or that it's adjusted correctly......The drive was probably filled correctly. If it wasn't, it would be junk by now.

The problem sounds like a defective or out of adjustment lower shift cable/shift plate assy etc.

It does need to be fixed. SOON. The drive won't survive long shifting like that.

 

[launboy]

Re: OMC Cobra Not Shifting Right

Well, an update to the thread.

I asked a few more questions and found out that this past summer, the drive has gotten worse. Now instead of the THUNK like it did the summer before, it is now a ggggrrrrrinnnndddd THUNK, then it goes into gear. I know that can't be good.

On top of that, he said that this fall it slipped their minds to fully drain the engine so, it has a little bit of water in the block. I guess we'll se what happens this spring when everything warms up. He said they might sell the bat anyway, because they are thinking of getting a new house, and it's hard to find one with a garage big enough to house the 20' boat with trailer.

Adam

 

[Don S]

Re: OMC Cobra Not Shifting Right

See, if you wait long enough, they do get worse.
Now you need a new drive, or a rebuild.
If only you had all the special tools, you could do it yourself. Or, if OMC still existed you could get it rebuilt locally.
Get your check book out, you are bound to find a fly by night that has something cheap.

 

[HT32BSX115]

Re: OMC Cobra Not Shifting Right

Doesn't sound too good.

They probably won't be getting much for that boat. A boat with an OMC Cobra and a cracked block is worth about $0

If they sell it, (Or give it away), whoever buys it will probably show up here asking about cracked blocks and bad shifting!

It's a vicious circle!