1989 OMC King Cobra Outdrive (460) shift cable replacement

[HT32BSX115]

I think some stringers used ESAs as well didn't they?

Looks like the '85 model did use some sort of ESA (according to the parts breakout at BRP) and although it's a different part number from the Cobra ESA's, it appears that newer replacement ESA's replace/supercede a number of the earlier ones.....

So I would say, yes. It appears that the Stringers used the same sort of "pulsing" type shift assist as the Cobras....Maybe the really early ones (Stringers) used a simple ignition interrupt?

 

[LiberatedCobra]

there is an "interruptor switch" up at the engine bellcrank, but as I can tell, something is frozen; the lower shift cable (Transom cable) will not move enough to shift the boat with power off and someone turning the prop. Unfortunately I havent had the time yet to remove the outdrive. Too busy keeping Helicopters in the air both here and abroad.

 

[LiberatedCobra]

The system itself seems relatively simple, I just don't know a good resource for replacement hardware such as upper gaskets, bushings for the hydraulics at the pivot pin, etc. Plus, the pivot pin itself is giving me trouble. Do any of you know if/where you can buy just the Knuckle at the end of the hydraulics that holds the pivot pin? Mine look in rough shape and I noticed that they are threaded on to the piston shaft. The local marina says that you have to purchase the entire hydraulic assy for $800!! If not, I will have to make some up.

 

[HT32BSX115]

The Cobra shift assist system is only actuated when you pull it out of gear. There's a "lever" system such that the force required to pull it out of gear is applied BEFORE the system actuates.

THEN, with the pressure (either tension or pressure on the cable depending if you're coming out of REV or FWD) on the actuator, the shift plate moves to operate the microswitch momentarily actuating the ESA while there's "out-of-gear" pressure on the lower shift cable.

The ignition pulsing causing the engine to "lope" removes enough torque on the dogs to pull them apart.

This all happens in several milliseconds. (or so)

If your lower shift cable is corroded, bent, damaged etc, the linkage is sticky/rusty/jammed either on top of the engine or down in the drive, then the pressure to just move the cable can be enough to move the shift plate and actuate the ESA any time you go into gear. which may "kill" the engine. The linkage and shift plate will "move" when going into gear..... but it shouldn't move enough to close the switch. If it does, the lower shift cable or linkage is usually the culprit.

For your engine, the linkage, cables, and switches are pretty much generic for all models of the Dog-clutch Cobra, but you may not be able to buy them new. You may have to scrounge.....(craigslist, ebay, junk-yards, etc)

There's several sites that have pictorials of parts for all the drives.

I like this one: http://epc.brp.com/ (email not required just click "View Parts Catalogs")

 

[LiberatedCobra]

thanks for the info. With actuation from the control, there is just enough motion/play to move the interruptor switch to kill the engine (if you try to hold the shift lever in whatever position fwd or rev). Upon release of the shift control lever, the system and shift control lever jump back into neutral thus depressing the switch allowing the engine to remain running.

I have recently found a 1989 Bayliner with the same power set-up as mine that I am thinking about buying; the price is low enough that it is almost worth it just for the engine/outdrive combo. I would feel bad junking the rest of the boat; the entire set-up is super clean, just not my style.

 

[bruceb58]

So...a little history here with OMC ESA. In the beginning, they used 2 switches. 1 is the interrupt switch which you are becoming familiar with and the other is the overstroke switch. The overstroke switch gets hit when the shift you are fully in gear in forward or reverse. It basically open up the path between the interrupt switch and the ESA. The thought is that when you are in gear, the interrupt switch should not be causing any ESA action.

Starting in about 1990, they got rid of the overstroke swittch and replaced the ESA with a design with a timer in it so the stumble only happens for a amximum amount of time. Back when I had my Cobra, I upgraded my ESA to this newer model. the CDI ESAs you buy also have that mod.

 

[LiberatedCobra]

After removing the outdrive, I found that the lower bellcrank was not being actuated due to the AFT guide sleeve "sticking" over the cable. There was a lot of build-up on the outer cable which was easily cleaned-off and now the the shift control can be actuated with one finger (w/o the outdrive installed). Now I will verify that the outdrive will shift, prior to installation, clean and re-lube all the components, and re-install the O/D. Also, I lucked out and found the upper seal kit at the local West Marine store for just over 3 bucks!

 

[LiberatedCobra]

the boat should make it's debut next week!