1989 Force 125: Gear Shift Interlock synch problem.

[shantyboat]

OK. I have an 89 125 HP with what appears to be an aftermarket remote control. (No makers name, but the various holes on the metal plate say "OMC" and "MERC" and so on.)

Questions:

Since the remote has a shift interlock, can I just remove the motor's manual interlock?

What the heck size nut is on the upper gear shaft?

Background: This remote is a two-stage control. Center neutral lock. Push forward or back to a detent to shift. Only beyond that point in fwd or rev can you advance the throttle.

I've replaced the control cables, which were stiff and probably 20 years old. They work great and the remote is smooth.

Engine stared right up and ran fine for several tests. But then the remote's shift function and the motor's "shift interlock" get out of synch.

As a result the arm on the towershaft is not fully retracted and the "interlock" plate presses above or below on it, causing a jam. I can manually reset the interlock by rotating the towershaft arm.

Paint scraping on the interlock plate shows this has been going on for a while, probably before I owned the boat.

I would adjust the interlock but it's almost impossible to get at.

Frankly, since the remote already has gearing that prevents whipping from forward to reverse at full throttle, I'd just like to take this interlock off. The service manual (page 129) and the parts diagram indicate this is something removable. The parts list neglects to give the size of the nuts.

Naturally it's barely accessible and I'm scouting for wrenches to take off the upper lock nut. The service manual makes the adjustment of the plate (up or down) seem real simple. It's not.

Advice, tips, whatnot !?

[Frank Acampora]

Advice: DON'T DO IT! The part you are describing is not an interlock but the actuator for the gearshift and the tab on the tower that rubs against it is the RPM limiter in neutral. Adjusting those nuts does not adjust the position of the plate, but the position of the gearshift rod. It is not a removable part.

The problem is in your cables and the control box. Bite the bullet and adjust them correctly. Throttle cable should have a longer, spring loaded quick-connect at the engine. Shift should have a shorter one. Cables are adjusted inside the control to about midway on the threads. Threaded ends at the engine are then adjusted to have correct throw.

[shantyboat]

I finally found the installation guide for the cables at the engine -- why it's not in the service manual I don't know. The cabes have the correct ends so it maybe be I need to tweak their position.

The service manual is a little oblique and makes this sound like a separate part, but it does appear to be attached to something else. It's not easy to see what goes to what. However, the service manual does say to adjust the position of this interlock (it's on the top of the upper gearshift rod) if necessary.

I'll take another look at it after tweaking the cables. Thanks for the info.