4.3 cobra shift problems

[stressfree]

have trouble getting netural underload.have to go over center for it to pop into netural.with the earmuffs on it works fine.underload you have the trouble.got new shift cable but marina was to busy so i thru outdrive back on.when i had the outdrive off the shift linkage i lubed good and it shifts good.i dont think it is the cable but i will change it when i can.anyway i shifted the outdive with the rod,forward and netural fine,netural to rev was not sliding right,or smooth.id say its deffenity is in the lower unit.what goes bad and how to fix it. noisey when idling with earmuffs on like dog clutchs are wore.looks like to many specialty tools needed to fix.nobody sell reasonably lower units rebuilt.or is it an easy fix to change dog clutches?

 

[WillyBWright]

Re: 4.3 cobra shift problems

How's your gearlue? Otherwise there's an ignition interrupt switch that's supposed to help when shifting into Neutral. I'm betting that's either disconnected, or the mechanism isn't functioning. A stiff thru-transom shift cable would cause this switch to stick and make the motor run badly, so I'm leaning more toward an inactive switch. Either a bad switch, bent lever, or not connected.<br /><br />Leave the drive innards alone. Difficulty getting Out of gear tends to relate more with that interrupt switch, difficulty getting Into gear might lead me inside the drive.

 

[rattana]

Re: 4.3 cobra shift problems

Your idle should not be above 700RPM orit will be hard to shift. Here is a site someone on iboats mentioned about setting up your shift cable. http://www.mercstuff.com/images/shiftcable.jpg

 

[stressfree]

Re: 4.3 cobra shift problems

the problem is in the lower unit,although the shift cable might of put it there.its not engaging right with the outdrive off the boat.seems like the dog cluch is worn from rev to netural.i guess what im after is finding out what kind of headacke it is to pull out the shaft and replace parts.then i have a new cable in box and a marnia to install it and set it up.my problem is if i go all the way with the marina it will be over $2000 if they do the cable and have to put gears in.boats not worth putting that kind of money in it.i looking at ether pulling the lower unit and replacing the gears or have someone do it then have the marina put the cable and adjust it.im very mechanicly incline so if someone changed the gears and not to much trouble ill do it.shop manual goes way out on rebuilding it.

 

[WillyBWright]

Re: 4.3 cobra shift problems

Well, you can do a Good job on it, or try to squeak by and hope for the best. For Reliability's sake, try the Manual's way first. As far as clutch dog engaging surfaces go, that's only one third of the equation. The Reverse and Forward gears are the other two thirds. If you totally mess things up, it's going to cost a whole lot more than that $2,000.<br /><br />One big thing to consider...the marina isn't going to guarantee someone else's work. If the drive roaches, they'll disavow all involvement. Guaranteed. To pull out the shaft, the lower gearcase has to be separated from the upper and the lower has to come pretty much completely apart. Not a job for the uninitiated without numerous special tools. You'll definately find you bit off more than you can chew.<br /><br />Sorry if this isn't what you wanted to hear, but I've put a lot of stuff back together that someone thought they could handle. Being able to do your own tune-ups and oil changes doesn't necessarily give me confidence that you could pull this one off. I personally would never dream of rebuilding my own automatic transmission because I know I'd end up carrying it into the tranny shop in pieces for somebody else to figure out. Outdrives I can do. Who knows, maybe the tranny mechanic would try the same thing and bring me his drive in parts. Wouldn't be the first time a car mechanic brought me a collection of boat parts to reassemble.

 

[Lowflyer]

Re: 4.3 cobra shift problems

David,<br />I would wager that the problem is NOT in lower unit. If it engages forward and it engages reverse, then the lower unit is doing its job. The clutch dog simply slides fwd or aft to engage those gears. The cable adjustment is the likely culpret. <br />As for the interrupt switch; another likely part of the problem. It can only work at very low RPM. If your carb is not backing down to idle for gear shifting, it will stay engaged. Check to ensure your throttle cable is allowing the carb linkage to idle all the way down against the screw. Otherwise, the RPMs stay up and its a ***** to get out of gear. Good Luck,<br />CJ

 

[stressfree]

Re: 4.3 cobra shift problems

the gears dont engage easy with the outdrive off.forward is ok but you have find reverse by working the shifting rod.if you own the boats you cant be afraid to work on them.do a water pump on a merc,you have half the unit apart to fix it.im from the 70,s hotrod days where you would rebuild an engine over the week and race it on the weekend.i thought this was the outdrive repair forum not the dont touch it take it to the dealer page.manuals are not user freindly if i took apart a unit i could explain the process easier than the book.the manual shows the whole rebuild but not the dog clutch replacement only.also somethimes you find a small shop that will rebuild the lower end for a lot less than a major rebuilder.

 

[stressfree]

Re: 4.3 cobra shift problems

ok worked on boat at shore sat.switchs work when you push them,but dont work when shifter is engaged.bracket was tight that swivels so i took off and cleaned and lubed.loose now but switched still dont engage when bracket swivels.gave up,took off wire harness and spliced in a kill button on dash,when im ready to shift i hold it for a second to kill the rrs and shift.seems to shift ok.when i do the cable ill have the guy look at the switches.still would like to change dog clutches if anyone knows how or someone reasonable.