OMC Stern Drive 400 wont shift into forward or reverse

grizzly2232

Recruit
Joined
Aug 18, 2013
Messages
4
We recently bought a boat at an auction sale that wont shift into forward or reverse. From what we can gather its an OMC Stern Drive 400 and was told its from 1984? The guy spent over 2000 in parts on the boat and only had it in the water once. Can anyone tell us what could possibly be wrong as well as how to take the lower part of the stern off?
 

Skipperlll

Cadet
Joined
Sep 2, 2011
Messages
12
Re: OMC Stern Drive 400 wont shift into forward or reverse

just recently re-built my upper and lower unit and know the tricks too.
providing you pressed the button on the shifter, try this.
1) remove shift cable from converter box going to the seat. try to shift, eliminate this cable.
2) rotate prop, try to shift using the arm on converter box. If moves. go to next step.
3) if arm moves your problem is in lower unit.
can be as simple as a clutch-dog pin, or a broken gear.
send more info for more help.
I can also step you through the lower unit with mechanical skill it can be done in hrs. depends on how much you need to do.
No special tools required, but a jerry rigged bearing puller and a 12" set of snap ring pliers.

Skipperlll
 

grizzly2232

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Joined
Aug 18, 2013
Messages
4
Re: OMC Stern Drive 400 wont shift into forward or reverse

The control box will be connected to the cable as you follow it back right? Dad figures it is the lower part. Can you tell us how to get it off?? Is there a bearing or something in there? We have all the bolts out that we can see but can't get it to come off. Thanks for all the help!!
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: OMC Stern Drive 400 wont shift into forward or reverse

I do not know what your are speaking of when you talk about 'all the bolts'.

There should be two cables leaving your helm shift/throttle control. One of them goes to the carburetor, the other to the shift converter arm. There is a pedestal on the converter box that has clamp on it to hold the outer cable and adjustment wheel. The little wheel that is on the terminus of that shift cable housing is what determines the length of throw of the inner cable that is hooked to the converter shift arm. It is that adjustment that you would use in the event the converter arm is not positioned in neutral at the same time the helm control is.

Don't mess with that roller adjustment until you determine that the drive will shift using the converter arm only. You need to pull the pin that holds the inner cable end on the converter shift arm so that you can manually actuate it.

Your converter should look like this. The cable from the outdrive enters the box on the upper right. The cable from the helm comes across from the left and is anchored on the post at the upper left. The inner core continues on and hooks up to the converter shift arm. This is where you need to disconnect it to manually actuate the converter and to eliminate that there is a problem from the converter box back to the drive itself. The lever only moves about an inch on either side of neutral. Don't pay attention to the decal marks on the box. Your neutral should be close to the center mark but not necessarily right on it. The converter arm pictured is in the forward gear position.

 
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grizzly2232

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Aug 18, 2013
Messages
4
Re: OMC Stern Drive 400 wont shift into forward or reverse

This is the converter box that we have on the boat. IMG_0671.jpg It wont let me upload any other pictures. We cant move that arm by hand and when you put it in gear you can easily turn the prop by hand and you cant hear anything. No clicking, nothing. What we are trying to do is take the lower gearcase off. Thats where we took all the bolts out of. well at least the obvious ones that we could see. We were told that chances are this is where our problem is when we talked to a guy from a boat shop near by but didnt give us anymore details.
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: OMC Stern Drive 400 wont shift into forward or reverse

That converter box is off of a hydro-mechanical drive (1978-1981). Shoot a side profile picture of your drive so we can see if the converter matches the drive.

If you have to remove the lower unit, you should completely remove the whole drive.
 
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Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: OMC Stern Drive 400 wont shift into forward or reverse

Yeah, that's it. Your drive matches your converter box. It is a 1978-1981 hydro-mechanical drive. I assume your boat is the same vintage.

Thing to do now is to remove the OD shift cable from the converter box and see if you can pull the individual cables into reverse and forward. Sometimes people screw up the threading of the cables into the converter. If that does not yield positive results, your going to have to pull the drive. Be very careful of that shift cable. It is very expensive. Once it is disconnected from the converter, you'll need to pull it out through the IH.
 
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