OMC Cobra Shift Problem

[CaptCrunch205]

Hello....I am a newbie to this site. My problem is two-fold. I have a 1989 Four Winns Sundowner 205 with a 5.0 Cobra (Ford). At the beginning of this season I purchased all the tools to remove the outdrive and align it. I needed to replace the gimbal bearing and replaced the bellows while it was apart. When I put it back together the shift fork and the bellcrank apparently were not aligned correctly and I bent the bellcrank. I bought a new bellcrank and installed it and made sure it was correctly aligned when I put it back together. Once it was together it worked great. I took it out this past Sunday and I lost reverse. No grinding or clunking just no reverse. After doing some searching I found out that you can't just throw a new bellcrank in there without going through and adjusting everything. So tonight I did the test of removing the lower shift cable and shifting it by hand into forward and reverse. It works when shifted by hand. So I am assuming that because I have no idea if the shift cable has ever been replaced that I should probably just replace the lower shift cable and go through the adjustment process to be sure it will work well for the future. That's the part one of the problem. When I replaced the bellows and gimbal bearing I ordered them for a 1989 5.0 Cobra. Last night when I was looking for the serial numbers for the outdrive I noticed that the numbers from the motor do not match the numbers on the outdrive. The motor numbers on the tag on the valve cover are 502APRMED with outdrive numbers of 985687 and TO638763. The numbers on the tag on the outdrive are 985685 and TO674669 with 4.3L stamped on it. They seem to run well together RPM's don't seem to run higher than any other boat that I have owned in the past. Am I OK with this outdrive or is it going to be a problem down the road? So in a huge nutshell....:sleeping: Should I replace the shift cable and go through the adjustment process and is the difference in the outdrive going to be a problem. I have no idea if it was rebuilt with the correct ratio gears. It's possible. Thanks......

 

[alldodge]

Howdy

Unable to answer your question but maybe I can get some folks here to have a look

Scott Danforth kenny nunez REDRIG

 

[CaptCrunch205]

Thank you AllDodge. I appreciate it.

Thanks,
Rob

 

[Lou C]

The number that starts with the 50----- is your OMC model # and this is what you usually order parts with. It sounds like you have the outdrive for a 4.3 V6 model which is closer to a 1.68 ratio, usually the V8s are 1.50 (5.0) and 1.41 (5.7). This may not really cause a problem in that it will be like a vehicle with a 3.90:1 final drive ratio vs a 3.55:1 or similar. This means if you had the standard prop you might go a bit over the max specified rpm (4600-4800) so after testing it you may be able to run a bit more pitch. The gears, bearings etc in the 4.3 drive are just as strong as the other small block V8 so no worries.

​OK back to the shift cable. You may or may not have to replace it, here's how to find out:
​Remove the drive, then disconnect the cable from the retainer that moves the bell crank.
​Then go up at the engine end and disconnect the transom shift cable from the bracket. So now its disconnected at both ends. Then get a fish scale and hook it to the cable. Pull the cable with it and see how much drag it has. If it 2.5 lbs or less (both directions) then its good. If more then you should replace it. In either case you use the special tools to adjust the transom shift cable with the drive off . Then reinstall the drive and adjust the remote cable with someone spinning the prop while you shift it (KEY OUT ENGINE OFF) so that they can feel for complete engagement in both FWD and REV.

​PS I have the bow rider version of your boat, except with the 4.3 Chevy 4-bbl. Nice running and riding boat.

 

[bruceb58]

The shift cable should be the same on all the dog shift Cobras. If you don't know how old it is, just change it. Buy an OEM one vs an after market.

Always store your outdrive in the down position. These cables fail right where they enter the drive, You will see the housing start to bulge.

If your console shifter is worn, that can also introduce a shifting issue due to lost motion in the control. Another place where you can get lost motion is the cable from the console shifter to the engine. Make sure it is supported along its entire length so it does not move while shifting. I used to tie wrap it to the steering cable.

Hopefully when you replaced your bellcrank, you bought the updated one with the bearing cap with the grease fitting on it. The updated bellcrank came out in 1991 or so. It allows you to fill the bellcrank cavity with grease after you put the drive on.

 

[CaptCrunch205]

So I didn't have to replace the shift cable. There was a little less than 2lbs of drag in both directions. It shifts very nicely in both forward and reverse. Now it is missing under load. I can baby it up on plane, but if I try to get on it, it bogs down like it is missing and there's no power. Is this a separate problem or is there something that is not adjusted correctly. I did find that the positive cable from the battery to the motor was run between the exhaust manifold and was rubbing against it. It was melted and obviously shorting out on the manifold. I wrapped the bad area in electrical tape and re-routed the cable so it was not running through the manifold. Thought that might be the problem, but it still acts the same. Can anyone point me in the right direction? Thanks......

 

[Lou C]

Well this could be a lot of things, for one, replace the battery cables (both with proper marine cable not the quick to corrode auto quality cable) and make sure that your terminals are clean and tight, on the starter solenoid and including the ground on the engine bellhousing stud behind the exhaust hose on the starboard side.
For another, it may need a complete tune up and these models had points and condenser ignition which works fine if maintained, but you may need to go through the whole ignition system (points, condenser, cap, rotor, plug wires, plugs, etc). If all that checks out, you can then make sure that the ESA is not staying engaged when its in gear although that would be more than just a miss, that would be a dramatic loss of power....

 

[CaptCrunch205]

Thanks Lou. I just wanted to make sure that it wasn't something that happened during the shift cable incident. It is a dramatic loss of power if I open it up. It won't plane out if I open it up. It takes the trim tabs pointing the nose down and babying it to get up on plane. It's possible that the ESA it engaged I will check that as well as the rest of the electrical system. I did points, cap, rotor and plugs at the beginning of the year last year. I will go through the whole thing though. It's only under load that it gets bad.

 

[Lou C]

One last thing is the anti siphon valve on the gas tank. This is a spring loaded valve that opens under suction from the fuel pump and closes when the engine is off. This prevents the fuel in the tank from siphoning into the bilge if the hose from the tank to the filter leaks. If they corrode internally they can stick & restrict fuel flow. My boat had this problem when we first got it about 15 years ago....

 

[bruceb58]

If you really want to know if its the ESA or not, just unplug the module. Just be aware that you won't be able to get the boat out of gear so do this in an area where you can safely turn off the boat after you run this test.