Re: Force 1987 125 cuts out at wot
That penny sized hole was due to detonation due to a lean run condition. With your idle mixture screws adjusted to more than one turn out from lightly seated, you should have no worry about a repeat---PROVIDED---that both carbs get the same amount of fuel. The best perventive measure would be to put a small plastic fuel filter between the carbs and fuel pump to keep a small piece of junk from clogging the inlet to one carb. See: when something causes a restiction in the fuel flow and both carbs go lean, the engine loses power and you notice before damage is done. When one carb goes lean, the other two pistons carry the engine and detonation happens before you can react. SO: The last thing that should happen to fuel before it is burned is filtering.
Water temperature in the engine is controlled to 160 degrees. Anything over 130 degrees will scald skin and cause a burn. So if you can hold your hand in it, it is not too hot. A better test is to put your finger on the powerhead near the head. It should be uncomfortably hot but not so hot that drop of water would boil off.
Now, as far as your miss, If it was missing that badly at full throttle I would not expect good running at say 1/2 throttle. Was it making a loud thump or bang as it "missed"? The boat will actually feel like it is jumping and you will see the engine bouncing. This would indicate possible dog clutch wear and the engine jumping in and out of gear. This would not happen at lower speeds, however the condition would get worse as it happened more often and the engine would jump out of gear at lower speeds.
If this accurately describes your condition, then you should take apart the lower unit and check for rounded edges on the gear dogs and/or clutch dogs. The clutch is rather expensive and the dogs can be re-ground to sharp edges as can the dogs on the gears. Since reverse gets a lot less wear and abuse, sometimes you can just flip the dog clutch over and use the better dogs to mate with the forward gear.
Then again, if this describes your condition, it could be due to improperly set shift linkage. You need to check that you have equal throw in both directions. If you have more travel in reverse, then forward dogs will not fully mate and will bounce out of gear. Below the engine pivot where the shift linkage goes into the lower unit, mark the rod in all three gear positions and measure the throw from neutral. Forward is down. The adjustment is under the bottom carb on the interlock plate. to increase forward, the top locknut is raised then the bottom nut is also raised to tighten the rod. this lowers the rod. Go small adjustments--1 turn or so-- at a time until shift travel is correct.
