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Experts please help 86 OMC gears not engaging Shift problem

L

Larry Dibble

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"I've read a few posts on

"I've read a few posts on shift system adjustments/ Transcom cables, etc. but can't narrow down my problem. I have a 86 OMC 5.0 (Chevy 305) that runs great, but the shifting is difficult, the gears are not engaging, and the prop only slightly turns with throttle. I disconnected the shift cables from the Transcom bracket and the shifting in both directions is smooth. The upper cable moves well going forward and back. The lower cable that goes into the sterndrive does not move forward and back when shifting (not sure if the lower cable is supposed to move but I suspect that it is). Anyways, I'm wondering if anyone with experience with this can give me some troubleshooting advice. Do I have a bad shift cable or possibly do the gears in the lower unit need adjusting? Or maybe they're bad? I just bought the boat and it was on the water recently. The propeller spins freely in the lower unit regardless of what gear it is in. --- But when you give it trottle it does begin to turn very slowly. It appears that the gears are not engaging or the shift cable needs adjusting or replacing but not quite sure. Thanks for any expertise in advance."
 
I would check the oil in the l

I would check the oil in the lower unit for metal pieces and then remove the drive and see if the lower shift cable is still stiff. It could be a bad cable or the bellcrank area at the end of the cable could be all cruddy (is that a word?) You should get yourself a manual if your going to try and do any work on it. I'm assuming it's a Cobra drive(1986)??? Does it have hydraulic trim cylinders on the drive or is there a big black rubber boot around the drive where it attaches to the transom?
 
Manual is on its way and I thi

Manual is on its way and I think I'll definately need it. The drive is an 86 Cobra stern drive and it does have the hydraulic trim cylinders on each side of the drive. It also has a black rubber boot (above the exhaust bellow) that is attached to the transom - not sure what that is yet. I'm guessing the first step in inspecting the drive cable inside the stern-drive is to detach the hydraulic arms and remove the upper unit? I also noticed that the exhaust bellow is also ripped up and need to be replaced. Thanks for your help Bob.
 
mine is the same except i can

mine is the same except i can go slow then give it gas and it disengages i am confused on this one ?!
 
"Larry....you have to rubber b

"Larry....you have to rubber bellows between the drive and transom plate. The lower one that you can see from underneath is the exhaust bellows, which by the way when you say torn the newer ones actually come manufactured with slits across the bottom of them now so confirm what you mean by torn. The bellows above that one is the drive shaft bellows where the shaft and u-joints are.


jolson...should always start a new thread for a new problem but if you can go slow and then give it some gas and the engine revs up but you don't go anywhere, the first thing to check is the prop, you may have a spun hub."
 
"Bob... I drained the oil from

"Bob... I drained the oil from the lower unit of the drive today. Prior to doing this, I checked the oil dip stick from the top of the upper case and it was so low that the oil didn't even hit the stick. However, when I drained the oil I got about 1 3/4 liters of oil out and it looked pretty good (dark and consistent in color/texture and no shavings in it). There was a very small amount of shavings magnetized to the lower drain screw but none in the oil so I think what I saw was due to normal wear. Could the oil being so low cause the gears/propellor not to turn? My next step is to remove the drive and check the lower shift cable from inside the drive. Also, when I remove the drive from the transom, do I need a special tool to realign the drive to the engine when I put it back on? Thanks again for your responses, you are very helpful and a great asset to the boating community."
 
"Larry...you gear oil sounds O

"Larry...you gear oil sounds OK and yes it's normal to have a small amount of shavings on the magnet. The drive should hole 64 oz, the oil being low won't cause the prop not to turn but it can/will cause the gears in the upper unit to trash themselves but you may have lucked out. Yes you should use an alignment tool before putting the drive back on, this makes sure the gimbal bearing is in alignment with the engine coupler, bad alignment will chew up the coupler and that means the engine has to come out. Quite often see them on eBay very reasonable. Also drop by your local marine supply to pick up a gasket set before installing the drive, should be under $10.

Also while you have the drive off, it's an excellent time to check your gimbal bearing for smoothness, take your hand and turn it as well chck and grease the u-joints and inspect the drive shaft bellows for any rips and stiffness, you don't want any water in there or it will destroy the gimbal bearing and u-joints."
 
"Bob... This update is for yo

"Bob... This update is for you! Took the stern drive off today and you were right, the shifting rod area was packed with crud which didn't allow the boat to shift. I removed the crud, relubed the whole setup, replaced the gasket, o-ring, and exhaust bellows that was torn so bad it was falling off, and put the drive back on. Reattached the batteries, powered her up, and the shifting and propulsion worked like a champ. I even got the local Marine shop to lend me the engine alignment tool for a couple hours at no charge. Thanks again for getting me going in the right direction. Your expert advise is definately appreciated and turned out fruitful in this case. My 86 Ebbtide is an old boat and I'm sure I'll have some challenges ahead in other areas, but for now, it appears she's ready to stretch her legs out on the Colorado River. Take care."
 
"Larry...glad you got it worki

"Larry...glad you got it working, hope you were able to check the gimbal bearing, u-joints and drive bellows with the drive off, a little preventative maintenance can go a long way...happy boating!"
 
I have 86 omc stringer v8 5.0 it will shift to reverse but will not engage forward I disconnected flat cable to drive I pulled short cable it went easy in gear pulled long cable very hard and will not engage forward so is this bad
 
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