84 force troubleshooting: lower unit might be shot

[ck85abc3]

I have a 1984 85HP Force single piece lower unit with non thru hub exaust. As I was pulling into the dock today I went to put it in reverse and it didn't have any thrust. The engine just reved up. The boat got blown into shore so I pulled it back out to the end of the dock and tied it up. I then put the trailer in the water and cranked the boat up because it was windy. I tried starting the boat and the starter would not engage. I later figured out that it was because the motor appears to be stuck in reverse.

Here are the major points of information I can give.

1. When it put the motor in gear it appears to not have any thrust and the motor just reved up.

2. I didn't hear any grinding or and clunks or clanks. Keep in mind that it was windy out though.

3. I generally can't push the throttle forwards into the forward gear position, but I can put the trottle backwords into the backwords gear position.

4. After a number of tries I did get the trottle into the forward gear position, but it did not change anything.

5. As I'm moving the thottle back and forth and can see the two cables moving back towards the motor.

6. I can turn the propeller by hand with *a lot* of force. So it appears to be in gear. As i'm turning the propeller by hand the motor is also turning over and I can hear the exaust come out the exaust port right above the propeller.

What do I do to start trouble shooting?

Thanks in advance.

 

[Frank Acampora]

Re: 84 force troubleshooting: lower unit might be shot

If you can force it into gear on shore and since it appears that it does not slip out while you are turning it by hand, it appears that the lower unit is ok.

First, disconnect the shift cable at the engine then try to move the shift linkage by hand. It should move with very little resistance. If it does not, then you have some binding somewhere. Since the only place where the shift linkage has any resistance, the most natural place to look, is the seal on the lower unit near the water pump. This seal sometimes swells and grabs the shift rod so tightly that shifting becomes a problem.

If the linkage does move smoothly by hand, then the chances are that the shift cable or control box has the problem.

It is possible that the sliding dog clutch inside the lower unit may be hanging up on the prop shaft, but I have never seen this happen in a gearcase that was not rusted badly. Most likely that is not the problem.

Another thought: At the bottom of the throttle tower linkage, there is an aluminum colored cam which is opposed to a white plate on the shift link. If these two are not synchronized to move out of each others way properly, the shift linkage will tend to jam up. In neutral, the two plates should be directly in line.
The throttle quick connect at the back of the engine should have about 1/4 to 3/8 inch of the spring loaded center showing. This allows the shift link to move and put the engine in gear before the throttle starts to move. If this is incorrect, the two plates will hit each other insted of bypassing and shifting will not be proper.

 

[ck85abc3]

Re: 84 force troubleshooting: lower unit might be shot

Looks like a clamp that connects to the shifter cable in the engine compartment came loose. Everythings good now. Thanks.

 

[Frank Acampora]

Re: 84 force troubleshooting: lower unit might be shot

I'm guilty of not using Occam's Razor: "The simplest solution to the problem is usually the correct one." ---OOPS! --never considered that the cable would not be properly connected.