Engine kicks under load

[Gibbily]

We have an OMC, 3L, 1988 or 89, cobra stern drive

A long time ago, out on the water there was a miss, jump, or whatnot with the engine. From then on out there are "jumps" about every 10 seconds, but it varies. These "jumps" make the whole engine kick sideways pretty hard. What's weird is that it only does these jumps under load, and in forwards, never reverse.

So we've been trying to find the problem, we have
1. Disassembled the outdrive (no problems there)
2. Rebuilt the carburetor
3. New plugs, plug wires
4. New cap rotor and points
5. Bypassed the fuel tank and the fuel pump
6. Bypassed the two ignition cutout switches
7. Gone through and loosened and retightened all wire connectors

If you have any idea please help, we're really fed up because of all the time we've put into it, and are about to just give it away. Thanks so much!

 

[Boobie]

Put a timing light on it and run it. When it does it turn the timing light around and look into it for any black spots. If you have them you have an ignition miss.

 

[racerone]

I believe there were issues with clutch dog jumping out of the forward gear.-----------So find a shop with the service bulletin on that subject.

 

[faztbullet]

That was the year they had the gear set update, the bellcrank kit,the cable change,etc,etc,etc.....

 

[bondo]

1. Disassembled the outdrive (no problems there)

Ayuh,... As noted above, the slidin' dog-clutch is worn out,....