Those darn micro switches?

[211libwtfo]

Ok same pile different stink. When I shift into forward the motor, 460 king cobra, stumbles as it should and goes into gear, when I shift to reverse it stumbles and keeps stumbling and reverse is almost impossible to use usually after jockeying neutral to reverse several times it will finally engage. My feeling is those micro switches but I'd rather get some expert advice from here

 

[Lou C]

Well to start with:
1) On the OMC Cobra drives with dog clutch shifting, the ESA is NOT supposed to engage when shifting into gear.
2) It is only supposed to engage, when shifting from in gear, to neutral.
3) Normal operation of the ESA, will feel like this, you will have the boat in gear at idle, then when you shift to neutral you should see the idle speed drop from about 600 rpm to 450, you will then feel the drive shift to neutral and the rpms will come back up to 600.

Either your shift cable is sticky or out of adjustment.

 

[211libwtfo]

Motor and cables 2years new 88 liberator and I'm not sure what to think that sounds exactly opposite of how this operates

 

[Lou C]

Need to find an ex OMC tech who knows what they are doing. I taught myself.

 

[211libwtfo]

Well either way I guess I'm looking for is it a cable adjustment or a faulty esn switch

 

[Lou C]

It could be both; if the cable is stiff it can cause the ESA to stay engaged in gear and if the screws holding the ESA to the engine bracket are too tight they can stick on.

 

[211libwtfo]

The shift cable is smooth and operates as it should except for the ifs and ands of this esn issue.

 

[Lou C]

Why not see if you can post up a vid of what it does when you shift it?

 

[211libwtfo]

I do have a video but I have a hard time posting any pics and video on this site. But it purs like a kitten, bb 460 thru hull exhaust, put it in forward you can hear the idle lower to a blahblah. Blah blah. Blahblah then as I ease more throttle the motor recovers and I can throttle to were ever that works perfectly. Then put to neutral idle,650rpm,is as it should be. Then put in reverse and motor goes to lower rpm more of blah-blah-blah-blah. And it take several minutes of jockeying throttle from reverse to neutral to actually get reverse to engage properly.

 

[bruceb58]

Sounds like your lower shift cable is sticking or your cable is not adjusted properly.

Do you store your drive in the down position? If you don't, that will cause this issue faster than if you keep it down.

The shift microswitch should be centered in the "V" of the cam on the shift plate when in neutral. Is it?

There is an overstroke switch that should stop the ESA from even working once you have fully shifted as well. The overstroke switch overrrides the shift switch. It basically opens the circuit between the shift switch and the ESA.

You can buy the upgraded ESA that came out in the early 90s that bypasses the overstroke switch and then uses a timer instead of the overstroke switch. Basically, it only allows the stumble to occur for a few seconds once the shift switch first makes contact. No rewiring is necessary, it overrides the switch in the harness of the ESA.

 

[211libwtfo]

Soo that would explain the two micro switches and why they're wired not like I'd expected soo I'm gonna go out on a limb and lean towards the lower or reverse needing adjusting because the switch works great in forward. Very very informative Bruce and really appreciate your input.

 

[bruceb58]

Here is how they are wired:

If you follow the wirng the from the bottom left of the connector, ground goes to the overstroke switchback through the connector, loops back to the shift switch and then back to the ESA. When you are fully shifted, the overstroke switch opens and the ground is removed from the ESA and stops the stumble.

 

[bruceb58]

Out of curiosity, do you boat in salt water and when was the last time you had the drive off? The area where the shift bellcrank lives is in a cavity in the pivot housing and gets water in it. This area can get full of deposits and will severely affect how easy the drive is to shift. This cavity needs to be completely filled with grease to prevent this issue.

EDIT: See you are in Illinois so unlikely you boat in the salt.

 

[211libwtfo]

Lol nope no salt here on the upper Mississippi well last time I checked anyway. I jus got a second to look at the rocker bracket and the roller of the switch is not exactly in the V of the neutral location I can definitely see the way the adjustment needs to go on the lower cable.

 

[bruceb58]

Lol nope no salt here on the upper Mississippi well last time I checked anyway. I jus got a second to look at the rocker bracket and the roller of the switch is not exactly in the V of the neutral location I can definitely see the way the adjustment needs to go on the lower cable.

There is only one way to properly adjust the lower shift cable. You need to pull the drive and use 2 OMC special tools that you can buy copies of on ebay.

http://www.ebay.com/itm/OMC-Cobra-S...ash=item4aeb298187:g:a-cAAOSw8cNUTU0v&vxp=mtr

 

[211libwtfo]

I guess what I don't understand is this lower shift cable goes to the throttle assembly sooo what does it have to do with anything of the outdrive. Ok had to get in the boat and check but yea the lower shift cable goes to the outdrive but to center the roller switch of the esn I can still make the adjustment at the motor bracket right?making the adjustment with the upper shift cable.?

 

[HT32BSX115]

Sounds like you're on the right path. The lower shift cable is the one that actually shifts the drive.via the shift actuator

There should NOT be enough force on the lower cable to cause the shift actuator (#37 below) to move far enough to actuate the switches when going into gear (or out of gear for that matter if the drive is being shifted out of gear with the boat sitting on the trailer.....this also means that you cannot test for actual correct shift actuator operation unless you test it in the water. )

When in the water, there is sufficient holding force due to torque on the shift dogs .....so that the ESA provided torque (reduction) pulses , will allow the shift dogs to separate when the shift actuator moves far enough to actuate the switches. and it will since you provide the extra pull (or push) to the cable coming out of gear.


As indicated above, if the lower cable or mechanism in the drive is binding even a little bit, it will take extra force to shift into (and out of) gear. THe extra force is usually enough to move the actuator enough to actuate the switches. If this is happening, you need to either replace the cable and/or clean up and /or lubricate the mechanism Bruce was talking aobut

 

[211libwtfo]

I'm going to lubricate the lower shift cable should I use graphite or silicon. And I'll make the adjustment to get the esn roller centered in the actuator bracket with the upper shift cable.

 

[bruceb58]

The cable should not be lubricated. If it's stiff, you need a new cable.

Do you store your drive down when you aren't using the boat?

 

[211libwtfo]

It is generally stored in the up position and the shifting works smoothly just the actuator bracket is out of alignment. Both cables are 2 years new.