Sick 120 v4 aro

[AK_FIREDOG]

My 1991 Johnson 120 w/jet unit is really starting to cut out at higher rpms (5000-5200). I have replaced the fuel pump, checked all fuel lines for leaks and changed out the sparke plugs. I set the gap at .30. It also cuts out under a load like, when I'm pulling a skier or a tube. Its seems to be ok when its not under a load. When it cuts out it drops rpms alittle around 4200, no change in the engine sound, however the throttle will be wide open and only turning 4000-4200 rpms. Now when I bring the throttle back to neutral then forward again its ok for a while, depending on the load and t&t. If I trim the motor up createing less load, the motor gets on step with out cutting out. I'm thinking about changing the sparke plug wires and coils. What do you guys think?

 

[ezeke]

Re: Sick 120 v4 aro

You may be overheating, causing S.L.O.W to kick in to protect the engine.

It would be a good time to check the water pump and thermostats.

Test your overheat alarm: Disconnect the two tan wires at the cylinder heads, turn the ignition key to run and ground the foreward ends of the tan wires to the block. The horn at the helm should sound a constant beep.

 

[AK_FIREDOG]

Re: Sick 120 v4 aro

kool thanks, I'll give that a try!