OMC Cobra Shifting Issue

[gh0st]

I have a 1990 OMC Cobra sterndrive (model number 985685) that someone swapped a 5.7 into at some point, and I am having issues setting up the shift cable to shift properly with the hand controls.

The first thing I did was disconnect the lower shift cable (the red cable), and tried to push/pull it into gear manually but it would only travel like an inch before binding up. So I removed the stern drive and found whoever worked on it last did not have the shift cable aligned with the shift rod when they assembled it. Manually moving the shift rod up and down, I am able to get the prop to fully lock and spin the drive shaft. So I put it back together and tried like hell trying to adjust the lower/remote cable to work properly with the hand shifter/throttle controls. The best I could get would be for it to lock into one gear, but not the other, even after adjusting that slide retaining nut.

My hand shifter/throttle control unit is shot (held together with electrical tape and prayers), so I was looking into getting a Teleflex CH1700 Series Side Mount Control to replace it with something reliable.

My question however, is which way the red throttle cable engages forward gear? Do you "push" the red cable in, or do you pull it out to engage forward gear? I am 99% certain I have a standard rotation sterndrive.

I am concerned that the new throttle control unit wont have enough shifter "cable throw" to fully engage into gear. Also I am not sure if I have the proper shift bracket mounted to the top of the motor.

I am almost tempted to buy and mount a separate hand shift lever that is independent of the throttle controls.

 

[nnl1987]

Your going to want to do a bit of reading and get yourself a manual as well. If someone has already been fiddling with it no telling of they set it up properly or not. If it's done incorrectly can do a lot of damage to the lower gears.

SHIFT SYSTEM ADJUSTMENTS for "KW-RG" (1986-1991) CLUTCH DOG MODELS

www.hastings.org

Start here. It will put you in the right direction. Any further questions this is definitely the place to ask! Don't run your boat until you get it sorted out!

 

[Lou C]

If you do a search on my user name I’ve posted how to adjust these; I’ve owned one for over 20 years.

 

[gh0st]

Your going to want to do a bit of reading and get yourself a manual as well. If someone has already been fiddling with it no telling of they set it up properly or not. If it's done incorrectly can do a lot of damage to the lower gears.

SHIFT SYSTEM ADJUSTMENTS for "KW-RG" (1986-1991) CLUTCH DOG MODELS

www.hastings.org

Start here. It will put you in the right direction. Any further questions this is definitely the place to ask! Don't run your boat until you get it sorted out!

Thanks for that resource. Turns out someone swapped out the original OMC 4.3L with a Mercruiser 5.7 and did not swap over the engine shift bracket back to the OMC kind. I ordered a used OMC engine shift bracket for a 4.3L (Im pretty sure it should fit the 5.7L). However it’s missing the ESA switch. Is there an updated version ESA kit brand new that fits the 4.3/5.7 (carburetor)? I think I read somewhere there’s a newer version that eliminated the overstroke switch. I need a part number/link to purchase a complete ESA kit. Thanks!

Here is the bracket currently on the boat:

 

[Lou C]

There were 2 different set ups used by OMC on the Cobras…
The early models had the module & 2 switches; an interrupt switch that lowers the idle when you shift to neutral; and the overstroke switch which over-rides the interrupt switch to keep it from engaging when the drive is in gear.
This can happen if the interrupt switch sticks on, which usually is a result of a worn out switch.

The later models used a simpler system with only the interrupt switch but the module incorporated a timer to keep it engaged only momentarily.

Not sure what you had originally the way to tell us to take your engine model # & look it up on Crowley Marine’s website then look at the diagrams to see if it had the 2 switch or one switch set up.
You need an OMC Shop Manual they are still available and I would look for the OMC Cobra article written by Stuart Hastings he does a good job of explaining how it is supposed to work.
If you can’t get the OEM parts CDI electronics sells them. I got both switches and a new module from them about 9 years ago. Still shifting perfect.

 

[Lou C]

Ok did some checking on what you had originally and what you have now. Best I can determine is that the change to the one switch set up occurred in 1990 so your boat may have had that originally. Up to & including 1989 they used the 2 switch set up. The brackets & associated parts are all different and what you bought to me looks just like the 2 switch set up. What I don’t know for sure is if you can use just the module with the timer & the interrupt switch only on that bracket or if you have to set it up like it originally was with the original module & 2 switches.
There is another solution which involves wiring it like a Merc Alpha which is simpler. In their system when the interrupt switch is triggered it momentarily shorts out the ignition to allow the drive to go into neutral. This works but the engine can stall if you shift too slowly or the cable is old & sticky.
OMCs system was more complex but when set up right was better; the engine idle is lowered to 450 rpm and if in good tune it won’t stall. Mine doesn’t; and it shifts with 2 finger pressure….
Hope this isn’t too confusing you have this issue because of what the previous owner did.
These are confusing because of changes made and they are all 30+ years old now. Properly set up though they work well.

 

[Lou C]

 

[Lou C]

 

[Lou C]

shift system in forward

shift system in reverse