Omc Cobra shift problems---- 5.7 1988

ab59

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thanks Lou--- I bought one the other day so it should be here tomorrow or the next day . Been storming and raining here again anyway so I'm thinking that by the time I get the part the storm will have passed .
Sure hope this does the trick , I'm ready to go fishing .

A.B.
 

ab59

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Well I talked to CDI and they told me that my new " Blaster " 0.7 ohms coil is too hot for the system and that I need to buy another one that is between 1 and 11/2 res. The two pin at the harness is 3 ohms.
This make 3.7 added together as is. If I add a coil that is 1.5 ohms that would be 5.2 ohms. making the resistance even greater ? I'm confused again, more so that I was before. I guess more ohms is less ? I dunno .
The old setup on the boat did not have a ballast resister on it at all.
 

Lou C

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The orginal OMC system with the points distributor had a resistance wire and a conventional coil. I hooked up the CDI moduel and it worked perfect for the past. 4 years. But since yours was changed, I would go with what they say. Think about it, less resistance equals more current flow.
 
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ab59

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Ok , guess I will buy another coil that has the 1.5 ohm rating. While I'm at it I will go ahead and buy the diode set up said to be the correct way to wire this thing. Makes me wonder how this was working before , it even had a bad coil . They shut down the Radio Shack here so I'll look for one in the next town. The ballast resistor at CDI is a little to spendy for my budget at 45.00 and up.
 

ab59

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ESA and resistor wire. I have the new ESA and directions on how to hook it up. My set up has the resistor wire instead of a Ballast Resistor . I bought a higher resistance coil and a 1.6 ohm ballast resistor that I bought for 8 bucks on line since the directions call for one.
My question is , why would I need two resistors ? Can I just leave out the new ballast resistor and call it good ? I did not make a diode set up because the new ESA instructions did not call for one.
The old ESA worked for 30 years as it is wired now. I dunno.
 

ab59

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Everything is together and I hear a stumble when I lift the detent by hand while running on muffs. Moving the shift actuator by hand does not effect the the engine RPM however. I'm hoping that this is because I'm not running the boat in the water . Still not enough water at the ramp down the street so guess I will make a trip to one of my favorite Crappie lakes down the road about 30 miles to give it a good test.
 

Lou C

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Correct, if it is set up right, when you shift out of gear on the water hose, it will not trigger the ESA but with the boat in the water it should.
 

ab59

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Thanks for your reply Lou---River was up thanks to some Heavy rains here and the water at the ramp was deep enough to put the boat in and test. I seem to have the same problem , It does not want to come out of gear and I could not hear the engine slow when trying to get into neutral. Again , if I reach down and pull the detent spring back where it contacts the interrupter switch button it will slow the engine. I will try again about mid week when there are not as many people at the ramp. Don't really want to have this problem at a lake ramp so I postponed my trip to the lake for testing.
Thanks again----A.B.
 

Lou C

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Man this thing has fought you all the way through hasn't it. Not sure what else to suggest but see if you can set up your phone to take a vid of it, when you shift it on the water, that will show us what it is doing. Actually thinking of selling mine. Ready for an outboard (going to be new or nearly new). Tired of I/Os and all the work. OK for young folks in fresh water. For cranky old guys in salt water, they are an enormous pain. Amazing I made it work so well this long.
 

ab59

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Well Lou you'll get a big Amen from me on the " no more sterndrives " sentiment . I had thought at first the the lower original cost of an engine and or outdrive was more cost effective than an outboard motor but I am no longer of that opinion. The extra work and time consumed trying to finish this never ending project has soured me forever on a inboard or sterndrive propulsion system.
To be fair though , I do not even consider buying a new outboard motor . For me a good used motor with good compression and a straight prop shaft is where my mindset is. I have never tried to rebuild an outboard but I do know that what you would pay a marine mechanic would be substantial and bears consideration in comparison of the two .
The lack of a separate outdrive is a blessing and also removes this nonsense PITA shift system from the equation.

I will try to remember my camera so I can show you what I'm doing and what the shift bracket setup is doing while I'm trying to adjust it to function correctly. Should be able to test again in a day or two.

thanks Lou------A.B.
 

ab59

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I got fed up and took the boat to a mechanic. He said I had everything right other than the idle was too low at about 500 rpm. I got the chance to go with him to a boat ramp as he was testing another boat as well and we backed her in the water and fired up the engine and after idle adjustment the shift problem showed it's ugly head again. He tried to adjust the lower ( transom ) cable and not the top controller cable and got it to shift from forward to neutral with no problem but could not find the sweet spot to make both gears return to neutral without hanging in gear. He then told me that the problem is in the outdrive and that no matter what the measurement was that I should adjust it a couple of turns.
Well don't get me wrong , I like the guy and he has done some good work for me at a good rate of pay in the past when I could not do it myself for whatever reason , that I was very happy with. He did not charge me for his attempt to adjust the shifting system. But I do not think that I will be taking his advise.
I brought the boat home and set everything up to shift from both gears to Neutral with the Interrupter Switch returning to the center of the V .
see vid----

https://youtu.be/TN30ben9egs

I then took the boat to my local ramp and of coarse the outdrive would not readily come out of gear back to neutral. While trying to edit some of the cussing out of the video I inadvertently destroyed the video at the ramp but the problem was the same. Hangs in gear for different amounts of time from any gear . My adjustments at the trunion did not seem to do much good . I could get it close in one gear but never for both and when I tried I lost the ability to shift from gear to neutral from either gear.
I seem to have come to an impasse . I will try once more to make another video of it in the water .

A.B.

https://youtu.be/OLhIZy50KBU
 

kpg7121

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Me, i would dump that OMC, repower with the conversion kit from SEI & be done with it. Cost you about $2k. Sell the drive to recoup some cash & sell the boat & go buy a boat with an OB.

​​​​Looks to me you've done what you can with it. Best of luck.
 

ab59

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Ramp results from test in the water. Almost correct but the sweet spot continues to elude me. Maybe someone can advise me after viewing the video, thanks---- A.B.--------------


https://youtu.be/hidyG29VZaM
 

Lou C

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Ok watched it...I did not hear any change in rpm when the load lever was supposed to trip the ESA interrupt switch. Is it lowering the idle or not? Normally should drop it to 450 rpm.
 

ab59

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I can't really tell either Lou . I do know that if I manually trip the interrupter switch by hand that it slows the engine . I can not seem the adjust the system to readily return the detent to the center of the V while it's in the water . I will take the boat back to the ramp again tomorrow if I can talk the little woman into going with me to shift while I am next to the engine where I can see and hear what is happening . Not Positive where I should be making the adjustment at to fine tune this . I think it should be at the control shift cable trunion. Note that it shifted just like it should the first time I shifted into Neutral from Forward gear and seemed to get further out of adjustment as I continued to shift in an out of gear .
thanks----A.B.
 

Lou C

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I’m pretty sure it is NOT activating. On mine it’s real obvious. Goes from a smooth idle to barely running then as soon as the shift is completed smooth again. If it seems to get more and more out of adjustment maybe the remote adjustment on the engine bell crank is slipping slightly.

Only other thing I can think of; if your cable and shifter bellcrank in the pivot housing are smooth and free....stiffness in the lower unit shift rod and shifter assembly in the lower unit. You should be able to shift this unit by hand pretty easily with the drive off using the shift rid while someone turns the driveshaft . If not could be s problem in the lower unit shifter assembly.
 

ab59

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Thanks for your reply Lou ---Keeping in mind that this outdrive shifted flawlessly before I replaced the shift cable I have a hard time thinking that the problem is in the outdrive or pivot bell crank. When I measured the height of the shift rod I also shifted the outdrive in and out of forward and reverse several time easily . The outdrive shifts into both gears and Neutral after outdrive installation .
I still believe that the problem must lay in the bracket adjustment . The words " the shift bracket arm should rock sharply " after adjustment in the manuals keeps coming to mind and what I need to to do insure that this is what is happening. I note that the interrupter switch arm does not seem to jump enough to make contact with the switch in such a way as to activate the ESA and for this reason I believe the problem to be in the adjustment not the outdrive itself.
I was hoping that the video would show something that I was overlooking but with so many different adjustments that need to be made to set the system up I guess it was another futile effort but I will continue to search for the answer.
It seems very close and I am leaning towards the bracket shift arm adjustment where the angled slot and the 7/16 " nut is as it appears that it is what puts tension on the actuator .
Being Sunday and having no one to shift for me , I will wait until tomorrow and go back to the ramp and make all my adjustments with the outdrive in the water and see if that does the trick.
Will see I guess.

thanks --A.B.
 
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Lou C

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In the one vid where you were shifting it on land it looked like the remote cable adjustment was all the way at the bottom end and usually mine is right in middle of the slot. Sure it’s right?
 
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