OMC Shifting-What SHOULD it feel like?

[duke3478]

I have a 1991 Four Winns 195 freedom, 4.3 v6 with OMC outdrive. When I got the boat, the Transom Bracket Shift Cable was shot, outer sheath rusted and nearly gone. It was the red, newer one, too.

About a year ago I replaced it with a new TBSC, following the Hastings recommendations as well as following what advice I could get here. The resistance on the TBSC was a little heavy, about 5 lbs, but I thought that was as good as it would get.

My shift issues for the past year were thus: Kind of grinds, then clunks into forward, stays engaged in reverse when coming to neutral until a little forward pressure applied.

So, while doing my summer service, took off the outdrive to replace both bellows, and to take another look at the TBSC. After realizing that I lubed it too much, cleaned out the sheath and inner core wire, and reinstalled. Resistance was then less than 2 lbs! I thought I had solved my dilemma. I carefully reinstalled everything, checking resistance as I went.

Bellcrank and related parts added no resistance at all. Everything there is true, square, and burr-free. Shift lever on outdrive itself is within adjustment specs and has very little resistance on its own. Probably a pound or less with someone turning prop.

I readjusted the carb to get everything really purring, and cleaned the spark arrestor, which was filthy with orange foam from inside of engine cover. (Replaced foam, too) My idle had been around 950rpm, so I adjusted that down to 600~650. Really lopes, but stays lit in gear.

Followed shift lever (the one the cables attach to under the engine cover) adjustments per hastings site and OMC manual. Neutral is neutral, and shifts at the right places.

Here is my current issue:

Nothing is really different. The gears still clatter then clunk into forward, and clunk hard into reverse. The remote lever seems as stiff as before, though it wasn't before I reinstalled the outdrive. But given the ease of shifting at the lower unit shift arm itself, I really don't think the issue is in the outdrive.

My gear oil was beautiful and golden after a year of use when I drained it, just a touch darker than new. Even with a year of grinding shifts, probably 300+ hours on the motor.

The lever where the trunnion attaches/rides doesn't seem to move at all. It seems to me it's intended to activate the Electronic Shift Assist. It doesn't.

What I'm wondering is what the final result is supposed to be. No one ever says what it should sound like going into gear, or how stiff the remote lever should be. For all I know, my boat is fine, but I really have nothing to compare it to. Can anyone say?

 

[bruceb58]

Re: OMC Shifting-What SHOULD it feel like?

If you are expecting the shift assist to operate when the boat is out of water, it won't and shouldn't if your lower cable is in good shape...sounds like it is. It needs the load on the gears with the propeller spinning in the water for it to work. It will only work going out of gear because of the loading on the gears.

You will get a clunk going into gear that is normal.

Your shift control will contribute to the extra pressure required to shift. If it is worn, it will require even more.

As far as the problem you have where it takes a little extra pressure forward to come out of neutral, your shift cable either needs to be adjusted slightly to get rid of that or there is lost motion in the controller and/or the cables. As the shifter wears, it will deliver less motion to the cable which cause you to lose the maximum motion of the cable. Another thing you should do is make sure the shift cable from the control to the engine is zip tied to support it along its entire length to something so it can not move. If that cable is flopping around, it contributes to lost motion and will make it harder to shift in and out of gear.

When I had my OMC Cobra, the best thing I ever did to help my shifting was buy a new remote control.

 

[duke3478]

Re: OMC Shifting-What SHOULD it feel like?

Thanks, Bruce. To clarify, the coming out of reverse problem was before my latest readjustment. I haven't been in the water yet, just on the muffs. Going today, so we'll see.

Also, reinstalled the control cable hangers (double zip-ties) you mentioned. My wires and cables were sagging undel the gunnel, completely on the floor in places. That should help, too.

I'll post my results after getting wet. I kind of thought the prop load would make a small difference. I need to stop shifting on the muffs, anyway.

 

[bruceb58]

Re: OMC Shifting-What SHOULD it feel like?

I need to stop shifting on the muffs, anyway.

No need to stop doing that. You are doing it with the engine running right? You need to do it to get the shift adjustments just right. I got really good at adjusting my shift cable on my Cobra. I had 2 shift cables replaced on my boat by someone other than me. First under warranty and second when I was at lake Powell and didn't have the proper tools. Both times, I had to go in after and readjust it so it worked properly. I did 2 more of the cables myself. Needless to say, I got good at replacing/adjusting the darn things.

 

[cr2k]

Re: OMC Shifting-What SHOULD it feel like?

You should NOT have lubed the cable. They are made to run as they are. Lube just adds resistance and drag to the cable.

Your controller may need service.

Last summer I worked on a cobra and had suspected it was the short cable, but like you when apart everything worked smooth. Then I pulled the control box apart and lubed up everything and wow everything worked like new.

 

[Juniinc]

Re: OMC Shifting-What SHOULD it feel like?

Nice boat, by the way.
I'm sure that U are shifting it briskly.
shift rod in the lower unit probably needs to be adjusted.

 

[bruceb58]

Re: OMC Shifting-What SHOULD it feel like?

shift rod in the lower unit probably needs to be adjusted.

Curious why you would say this. Typically, that shift rod never needs to be touched unless the lower unit is disassembled.

 

[duke3478]

Re: OMC Shifting-What SHOULD it feel like?

Yeah, I left the shift rod alone. It measured up right. Thanks for the boat compliments! I love it, only paid $2700 and got a nice cover, untouched factory camper top and bimini, and the easiest to load trailer I have ever used. Only in it for a couple hundred extra for miscellaneous stuff, a prop, a TBSC and two or three outdrive gaskets. Definitely gotten my money's worth in memories already.

Back to business, had my first trip tonight after new adjustments. Idle adjustment really helped. Shifts much better, clicks into reverse, clunks into forward, and comes out of gear to neutral with a whisper. Only thing is, after it clunks into forward, it rattles, then continues to rattle until i give it some forward pressure, usually past idle speed. Not a good trait when trailering or docking.

My thought is that it's favoring reverse a little. So would the wisest thing to get rid of the bias be to adjust:

1. The TBSC trunnion
2. The remote cable's trunnion or
3. The remote cable's position in the slot on the shift arm

Seems like the TBSC trunnion is the most obvious, but it's shifting into reverse so well, I hate to lose that adjustment.

I'm having trouble getting my head around what does what. Seems like every adjustable thing relies on another. I need more forward throw at the TBSC but equal reverse throw, and for neutral to stay put. Is that even possible?

Thanks again for the great advice and encouragement.

 

[bruceb58]

Re: OMC Shifting-What SHOULD it feel like?

If anything, I always give a slight more bias to going into forward. My reason is that if you go out of adjustment at any point you want more throw toward forward since it is more crtical since forward is what you are doing full throttle starts on. If you aren't all the way into the dog gears and you do a full throttle start, popping out will do some damage. You rarely do much more than idle with reverse.

Not exactly sure what you mean by your 3 choices but just adjust the lower shift cable at the top of the engine.

Also, remember what I said about lost motion with a control that is worn. That could easily be another source of your problems.

 

[duke3478]

Re: OMC Shifting-What SHOULD it feel like?

By TBSC trunnion I mean the barrel-shaped piece (mine is brass, hastings site says it's black plastic) that threads on the top end of the TBSC and spins forward or back to adjust the distance the TBSC travels.

By control cable trunnion I mean the adjusting nut/wheel that adjusts the relationship of the control cable to the shift arm.

By shift arm I mean the bar that levers back and forth, with the slot in the top, where the control cable attaches in the slot and the TBSC attaches on the bottom pin.

I think any one of these will affect the other. I just don't want to screw one up by changing another. If the forward throw can be changed without changing the reverse throw, I'd like to do that. Just not sure if I can. I thought the diagonal slot in the shift arm might allow for that.

 

[a70eliminator]

Re: OMC Shifting-What SHOULD it feel like?

Brisk shifts as mentioned is a good practice, I know my cobra skips a couple beats if I move the shift lever slowly into forward or reverse but if I shift using just a little authority it will lock in beautifully, shift technique does have an effect.

 

[Juniinc]

Re: OMC Shifting-What SHOULD it feel like?

Sup Bruce,
We had to do that to my brother's old OMC.
It was way off, who knows? what that old cobra's been through.

Hey Duke, Have you tried with the throttle cable disconnected?

Curious why you would say this. Typically, that shift rod never needs to be touched unless the lower unit is disassembled.

 

[duke3478]

Re: OMC Shifting-What SHOULD it feel like?

Hey Duke, Have you tried with the throttle cable disconnected?

Not in the water. I'm sure it would go into forward okay, because I could give it the extra 1/4" or so of stick it needs without the carb opening up above idle. I don't think cable resistance is the problem now, just needs a little more forward travel without sacrificing reverse travel.

 

[duke3478]

Re: OMC Shifting-What SHOULD it feel like?

Brisk shifts as mentioned is a good practice, I know my cobra skips a couple beats if I move the shift lever slowly into forward or reverse but if I shift using just a little authority it will lock in beautifully, shift technique does have an effect.

Yeah, I go to at least the forward detent without stopping, and instruct anyone else who drives to do the same. That worked well even before my latest adjustments. Just grinded more because my idle was higher, etc.